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Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
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1

Expert system for online surveillance of nuclear reactor coolant pumps  

DOE Patents [OSTI]

An expert system for online surveillance of nuclear reactor coolant pumps. This system provides a means for early detection of pump or sensor degradation. Degradation is determined through the use of a statistical analysis technique, sequential probability ratio test, applied to information from several sensors which are responsive to differing physical parameters. The results of sequential testing of the data provide the operator with an early warning of possible sensor or pump failure.

Gross, Kenny C. (Bolingbrook, IL); Singer, Ralph M. (Naperville, IL); Humenik, Keith E. (Columbia, MD)

1993-01-01T23:59:59.000Z

2

Evaluation of Buildup of Activated Corrosion Products for Highly Compact Marine Reactor DRX without Primary Coolant Water Purification System  

E-Print Network [OSTI]

Evaluation of Buildup of Activated Corrosion Products for Highly Compact Marine Reactor DRX without Primary Coolant Water Purification System

Odano, N

2000-01-01T23:59:59.000Z

3

Reactor coolant pump flywheel  

DOE Patents [OSTI]

A flywheel for a pump, and in particular a flywheel having a number of high density segments for use in a nuclear reactor coolant pump. The flywheel includes an inner member and an outer member. A number of high density segments are provided between the inner and outer members. The high density segments may be formed from a tungsten based alloy. A preselected gap is provided between each of the number of high density segments. The gap accommodates thermal expansion of each of the number of segments and resists the hoop stress effect/keystoning of the segments.

Finegan, John Raymond; Kreke, Francis Joseph; Casamassa, John Joseph

2013-11-26T23:59:59.000Z

4

System and method for determining coolant level and flow velocity in a nuclear reactor  

DOE Patents [OSTI]

A boiling water reactor includes a reactor pressure vessel having a feedwater inlet for the introduction of recycled steam condensate and/or makeup coolant into the vessel, and a steam outlet for the discharge of produced steam for appropriate work. A fuel core is located within a lower area of the pressure vessel. The fuel core is surrounded by a core shroud spaced inward from the wall of the pressure vessel to provide an annular downcomer forming a coolant flow path between the vessel wall and the core shroud. A probe system that includes a combination of conductivity/resistivity probes and/or one or more time-domain reflectometer (TDR) probes is at least partially located within the downcomer. The probe system measures the coolant level and flow velocity within the downcomer.

Brisson, Bruce William; Morris, William Guy; Zheng, Danian; Monk, David James; Fang, Biao; Surman, Cheryl Margaret; Anderson, David Deloyd

2013-09-10T23:59:59.000Z

5

Secondary Startup Neutron Sources as a Source of Tritium in a Pressurized Water Reactor (PWR) Reactor Coolant System (RCS)  

SciTech Connect (OSTI)

The hypothesis of this paper is that the Zircaloy clad fuel source is minimal and that secondary startup neutron sources are the significant contributors of the tritium in the RCS that was previously assigned to release from fuel. Currently there are large uncertainties in the attribution of tritium in a Pressurized Water Reactor (PWR) Reactor Coolant System (RCS). The measured amount of tritium in the coolant cannot be separated out empirically into its individual sources. Therefore, to quantify individual contributors, all sources of tritium in the RCS of a PWR must be understood theoretically and verified by the sum of the individual components equaling the measured values.

Shaver, Mark W.; Lanning, Donald D.

2010-02-01T23:59:59.000Z

6

Method for removing cesium from a nuclear reactor coolant  

DOE Patents [OSTI]

A method of and system for removing cesium from a liquid metal reactor coolant including a carbon packing trap in the primary coolant system for absorbing a major portion of the radioactive cesium from the coolant flowing therethrough at a reduced temperature. A regeneration subloop system having a secondary carbon packing trap is selectively connected to the primary system for isolating the main trap therefrom and connecting it to the regeneration system. Increasing the temperature of the sodium flowing through the primary trap diffuses a portion of the cesium

Colburn, Richard P. (Pasco, WA)

1986-01-01T23:59:59.000Z

7

Evaluation of nuclear facility decommissioning projects. Three Mile Island Unit 2 reactor coolant system and systems decontamination. Summary status report. Volume 1  

SciTech Connect (OSTI)

This document summarizes information relating to the decontamination and restoration of the Three Mile Island Unit 2 reactor coolant system and other plant systems. Data have been collected from activity reports, reactor containment entry records, and other sources and entered in a computerized data system which permits extraction/manipulation of specific data which can be used in planning for recovery from a loss of coolant event similar to that experienced by the Three Mile Island Unit 2 on March 28, 1979. This report contains a summary of radiation exposures, manpower, and time spent in radiation areas during the referenced period. Support activities conducted outside of radiation areas are not included. Computer reports included are: A chronological listing of all activities related to decomtamination and restoration of the reactor coolant system and other plant systems for the period of April 5, 1979, through December 19, 1984; a summary of labor and exposures by department for the same time period; and summary reports for each major task undertaken in connection with this specific work scope during the referenced time period.

Doerge, D.H.; Miller, R.L.; Scotti, K.S.

1986-05-01T23:59:59.000Z

8

Environmentally Friendly Coolant System  

SciTech Connect (OSTI)

Energy reduction through the use of the EFCS is most improved by increasing machining productivity. Throughout testing, nearly all machining operations demonstrated less land wear on the tooling when using the EFCS which results in increased tool life. These increases in tool life advance into increased productivity. Increasing productivity reduces cycle times and therefore reduces energy consumption. The average energy savings by using the EFCS in these machining operations with these materials is 9%. The advantage for end milling stays with flood coolant by about 6.6% due to its use of a low pressure pump. Face milling and drilling are both about 17.5% less energy consumption with the EFCS than flood coolant. One additional result of using the EFCS is improved surface finish. Certain machining operations using the EFCS result in a smoother surface finish. Applications where finishing operations are required will be able to take advantage of the improved finish by reducing the time or possibly eliminating completely one or more finishing steps and thereby reduce their energy consumption. Some machining operations on specific materials do not show advantages for the EFCS when compared to flood coolants. More information about these processes will be presented later in the report. A key point to remember though, is that even with equivalent results, the EFCS is replacing petroleum based coolants whose production produces GHG emissions and create unsafe work environments.

David Jackson Principal Investigator

2011-11-08T23:59:59.000Z

9

Control of reactor coolant flow path during reactor decay heat removal  

DOE Patents [OSTI]

An improved reactor vessel auxiliary cooling system for a sodium cooled nuclear reactor is disclosed. The sodium cooled nuclear reactor is of the type having a reactor vessel liner separating the reactor hot pool on the upstream side of an intermediate heat exchanger and the reactor cold pool on the downstream side of the intermediate heat exchanger. The improvement includes a flow path across the reactor vessel liner flow gap which dissipates core heat across the reactor vessel and containment vessel responsive to a casualty including the loss of normal heat removal paths and associated shutdown of the main coolant liquid sodium pumps. In normal operation, the reactor vessel cold pool is inlet to the suction side of coolant liquid sodium pumps, these pumps being of the electromagnetic variety. The pumps discharge through the core into the reactor hot pool and then through an intermediate heat exchanger where the heat generated in the reactor core is discharged. Upon outlet from the heat exchanger, the sodium is returned to the reactor cold pool. The improvement includes placing a jet pump across the reactor vessel liner flow gap, pumping a small flow of liquid sodium from the lower pressure cold pool into the hot pool. The jet pump has a small high pressure driving stream diverted from the high pressure side of the reactor pumps. During normal operation, the jet pumps supplement the normal reactor pressure differential from the lower pressure cold pool to the hot pool. Upon the occurrence of a casualty involving loss of coolant pump pressure, and immediate cooling circuit is established by the back flow of sodium through the jet pumps from the reactor vessel hot pool to the reactor vessel cold pool. The cooling circuit includes flow into the reactor vessel liner flow gap immediate the reactor vessel wall and containment vessel where optimum and immediate discharge of residual reactor heat occurs.

Hunsbedt, Anstein N. (Los Gatos, CA)

1988-01-01T23:59:59.000Z

10

Automatic coolant flow control device for a nuclear reactor assembly  

DOE Patents [OSTI]

A device which controls coolant flow through a nuclear reactor assembly comprises a baffle means at the exit end of said assembly having a plurality of orifices, and a bimetallic member in operative relation to the baffle means such that at increased temperatures said bimetallic member deforms to unblock some of said orifices and allow increased coolant flow therethrough.

Hutter, Ernest (Wilmette, IL)

1986-01-01T23:59:59.000Z

11

Automatic coolant flow control device for a nuclear reactor assembly  

DOE Patents [OSTI]

A device which controls coolant flow through a nuclear reactor assembly comprises a baffle means at the exit end of said assembly having a plurality of orifices, and a bimetallic member in operative relation to the baffle means such that at increased temperatures said bimetallic member deforms to unblock some of said orifices and allow increased coolant flow therethrough.

Hutter, E.

1984-01-27T23:59:59.000Z

12

Technical note Coolant void worth in fast breeder reactors  

E-Print Network [OSTI]

., 1974; Murata and Mukaiyama, 1984) and deuterium­tritium fusion neutron sources (Rose et al., 1977. Finally, we investigate the coolant void worth in various types of model critical and ADS transmutation systems, employing nitride and oxide fuel, different types of inert matrices and two types of coolants

13

Reactor vessel support system  

DOE Patents [OSTI]

A reactor vessel support system includes a support ring at the reactor top supported through a box ring on a ledge of the reactor containment. The box ring includes an annular space in the center of its cross-section to reduce heat flow and is keyed to the support ledge to transmit seismic forces from the reactor vessel to the containment structure. A coolant channel is provided at the outside circumference of the support ring to supply coolant gas through the keyways to channels between the reactor vessel and support ledge into the containment space.

Golden, Martin P. (Trafford, PA); Holley, John C. (McKeesport, PA)

1982-01-01T23:59:59.000Z

14

Reactor vessel support system. [LMFBR  

DOE Patents [OSTI]

A reactor vessel support system includes a support ring at the reactor top supported through a box ring on a ledge of the reactor containment. The box ring includes an annular space in the center of its cross-section to reduce heat flow and is keyed to the support ledge to transmit seismic forces from the reactor vessel to the containment structure. A coolant channel is provided at the outside circumference of the support ring to supply coolant gas through the keyways to channels between the reactor vessel and support ledge into the containment space.

Golden, M.P.; Holley, J.C.

1980-05-09T23:59:59.000Z

15

Coolant flows in prismatic fuel and particle bed nuclear reactors for rocket applications  

SciTech Connect (OSTI)

Semiempirical expressions for pressure losses in prismatic and particle bed reactors for nuclear propulsion are combined with the geometric characteristics of core configurations and coolant flow patterns. The results are used to illustrate a limitation on the coolant velocity and to develop a unified approach to a quantitative comparison of merits and demerits of different reactor core concepts intended for space applications.

Bohachevsky, I.O. (Rocketdyne Division FA44, Rockwell International Corporation, 6633 Canoga Avenue, Canoga Park, California 91309-7922 (United States))

1993-01-20T23:59:59.000Z

16

Load following capability of CANDLE reactor by adjusting coolant operation condition  

SciTech Connect (OSTI)

The load following capability of CANDLE reactor is investigated in the condition that the control rods are unavailable. Both sodium cooled metallic fuel fast reactor (SFR) and {sup 208}Pb cooled metallic fuel fast reactor (LFR) are investigated for their performance in power rate changing by changing its coolant operation condition; either coolant flow rate or coolant inlet temperature. The change by coolant flow rate is difficult especially for SFR because the maximum temperature criteria on cladding material may be violated. The power rate can be changed for its full range easily by changing the coolant temperature at the core inlet. LFR can reduce the same amount of power rate by smaller change of temperature than SFR. However, the coolant output temperature is generally decreased for this method and the thermal efficiency becomes worse.

Sekimoto, Hiroshi; Nakayama, Sinsuke [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology 2-12-1-N1-17, Ookayama, Meguro-ku 152-8550 (Japan)

2012-06-06T23:59:59.000Z

17

Liquid metal cooled nuclear reactor plant system  

DOE Patents [OSTI]

A liquid metal cooled nuclear reactor having a passive cooling system for removing residual heat resulting for fuel decay during reactor shutdown, or heat produced during a mishap. The reactor system is enhanced with sealing means for excluding external air from contact with the liquid metal coolant leaking from the reactor vessel during an accident. The invention also includes a silo structure which resists attack by leaking liquid metal coolant, and an added unique cooling means.

Hunsbedt, Anstein (Los Gatos, CA); Boardman, Charles E. (Saratoga, CA)

1993-01-01T23:59:59.000Z

18

Large break loss-of-coolant accident analyses for the high flux isotope reactor  

SciTech Connect (OSTI)

The US Department of Energy's High Flux Isotope Reactor (HFIR) was analyzed to evaluate it's response to a spectrum of loss-of-coolant accidents (LOCAs) with potential for leading to core damage. The MELCOR severe accident analysis code (version 1.7.1) was used to evaluate the overall dynamic response of HFIR. Before conducting LOCA analyses, the steady-state thermal-hydraulic parameters evaluated by MELCOR for various loop sections were verified against steady-state operating data. Thereafter, HFIR depressurization tests were simulated to evaluate the system pressure change for a given depletion in coolant inventory. Interesting and important safety-related phenomena were observed. The current analyses (which should be considered preliminary) that occur over a period from 1 to 3 seconds do not lead to core wide fuel melting. Core fluid flashing during the initial rapid depressurization does cause fuel temperature excursions due to adiabatic-like heatup. 3 refs., 4 figs.

Taleyarkhan, R.P. (Oak Ridge National Lab., TN (USA))

1989-01-01T23:59:59.000Z

19

Waste Heat Recovery from the Advanced Test Reactor Secondary Coolant Loop  

SciTech Connect (OSTI)

This study investigated the feasibility of using a waste heat recovery system (WHRS) to recover heat from the Advanced Test Reactor (ATR) secondary coolant system (SCS). This heat would be used to preheat air for space heating of the reactor building, thus reducing energy consumption, carbon footprint, and energy costs. Currently, the waste heat from the reactor is rejected to the atmosphere via a four-cell, induced-draft cooling tower. Potential energy and cost savings are 929 kW and $285K/yr. The WHRS would extract a tertiary coolant stream from the SCS loop and pump it to a new plate and frame heat exchanger, from which the heat would be transferred to a glycol loop for preheating outdoor air supplied to the heating and ventilation system. The use of glycol was proposed to avoid the freezing issues that plagued and ultimately caused the failure of a WHRS installed at the ATR in the 1980s. This study assessed the potential installation of a new WHRS for technical, logistical, and economic feasibility.

Donna Post Guillen

2012-11-01T23:59:59.000Z

20

Computational study: Reduction of iron corrosion in lead coolant of fast nuclear reactor  

SciTech Connect (OSTI)

In this paper we report molecular dynamics simulation results of iron (cladding) corrosion in interaction with lead coolant of fast nuclear reactor. The goal of this work is to study effect of oxygen injection to the coolant to reduce iron corrosion. By evaluating diffusion coefficients, radial distribution functions, mean-square displacement curves and observation of crystal structure of iron before and after oxygen injection, we concluded that a significant reduction of corrosion can be achieved by issuing about 2% of oxygen atoms into lead coolant.

Arkundato, Artoto; Su'ud, Zaki; Abdullah, Mikrajuddin; Widayani [Physics Department, ITB, Bandung (Indonesia) and Physics Department, University of Jember, Jl. Kalimantan III/25, Jember (Indonesia); Physics Department, ITB Jl. Ganesha 10, Bandung (Indonesia)

2012-06-20T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Effects of light water reactor coolant environment on the fatigue lives of  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Effects of light water reactor coolant environment on the fatigue lives of Effects of light water reactor coolant environment on the fatigue lives of reactor materials July 8, 2013 A metal component can become progressively degraded, and its structural integrity can be adversely impacted when it is subjected to repeated fluctuating loads, or fatigue loading. Fatigue loadings on nuclear reactor pressure vessel components can occur because of changes in pressure and temperature caused by transients during operation, such as reactor startup or shutdown and turbine trip events. The American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code recognizes fatigue as a possible cause of failure of reactor materials and provides rules for designing nuclear power plant components to avoid fatigue failures. For various materials, the ASME Code defines the

22

EXPERIMENT OPERATIONS PLAN FOR A LOSS-OF-COOLANT ACCIDENT SIMULATION IN THE NATIONAL RESEARCH UNIVERSAL REACTOR  

SciTech Connect (OSTI)

Pressurized water reactor loss-of-coolant accident phenomena are being simulated with a series of experiments in the U-2 loop of the National Research Universal Reactor at Chalk River, Ontario, Canada. The first of these experiments includes up to 45 parametric thermal-hydraulic tests to establish the relationship between the reflood delay time of emergency coolant, the reflooding rate, and the resultant fuel rod cladding peak temperature. This document contains both experiment proposal and assembly proposal information. The intent of this document is to supply information required by the Chalk River Nuclear Laboratories (CRNL), and to identify the planned procedures and data that will be used both to establish readiness to proceed from one test phase to the next and to operate the experiment. Operating control settings and limits are provided for both experimenter systems and CRNL systems. A hazards review summarizes safety issues that have been addressed during the development of the experiment plan.

Russcher, G. E.; Cannon, L. W.; Goodman, R. L.; Hesson, G. M.; King, L. L.; McDuffie, P. N.; Marshall, R. K.; Nealley, C.; Pilger, J. P.; Mohr, C. L.

1981-04-01T23:59:59.000Z

23

Nuclear reactor with low-level core coolant intake  

DOE Patents [OSTI]

A natural-circulation boiling-water reactor has skirts extending downward from control rod guide tubes to about 10 centimeters from the reactor vessel bottom. The skirts define annular channels about control rod drive housings that extend through the reactor vessel bottom. Recirculating water is forced in through the low-level entrances to these channels, sweeping bottom water into the channels in the process. The sweeping action prevents cooler water from accumulating at the bottom. This in turn minimizes thermal shock to bottom-dwelling components as would occur when accumulated cool water is swept away and suddenly replaced by warmer water.

Challberg, Roy C. (Livermore, CA); Townsend, Harold E. (Campbell, CA)

1993-01-01T23:59:59.000Z

24

Cooling system for a nuclear reactor  

DOE Patents [OSTI]

A cooling system for a gas-cooled nuclear reactor is disclosed which includes at least one primary cooling loop adapted to pass coolant gas from the reactor core and an associated steam generator through a duct system having a main circulator therein, and at least one auxiliary cooling loop having communication with the reactor core and adapted to selectively pass coolant gas through an auxiliary heat exchanger and circulator. The main and auxiliary circulators are installed in a common vertical cavity in the reactor vessel, and a common return duct communicates with the reactor core and intersects the common cavity at a junction at which is located a flow diverter valve operative to effect coolant flow through either the primary or auxiliary cooling loops.

Amtmann, Hans H. (Rancho Santa Fe, CA)

1982-01-01T23:59:59.000Z

25

Evaluation of the coolant reactivity coefficient influence on the dynamic response of a small LFR system  

SciTech Connect (OSTI)

An assessment of the coolant reactivity feedback influence on a small Lead-cooled Fast Reactor (LFR) dynamics has been made aimed at providing both qualitative and quantitative insights into the system transient behavior depending on the sign of the above mentioned coefficient. The need of such an investigation has been recognized since fast reactors cooled by heavy liquid metals show to be characterized by a strong coupling between primary and secondary systems. In particular, the coolant density and radial expansion coefficients have been attested to play a major role in determining the core response to any perturbed condition on the Steam Generator (SG) side. The European Lead-cooled System (ELSY)-based demonstrator (DEMO) has been assumed as the reference LFR case study. As a first step, a zero-dimensional dynamics model has been developed and implemented in MATLAB/SIMULINK{sup R} environment; then typical transient scenarios have been simulated by incorporating the actual negative lead density reactivity coefficient and its opposite. In all the examined cases results have shown that the reactor behaves in a completely different way when considering a positive coolant feedback instead of the reference one, the system free dynamics resulting moreover considerably slower due to the core and SG mutually conflicting reactions. The outcomes of the present analysis may represent a useful feedback for both the core and the control system designers. (authors)

Lorenzi, S.; Bortot, S.; Cammi, A.; Ponciroli, R. [Dept. of Energy, Nuclear Engineering Div. - CeSNEF, Politecnico di Milano, Via La Masa 34, 20156 Milano (Italy)

2012-07-01T23:59:59.000Z

26

Containment system for supercritical water oxidation reactor  

DOE Patents [OSTI]

A system is described for containment of a supercritical water oxidation reactor in the event of a rupture of the reactor. The system includes a containment for housing the reaction vessel and a communicating chamber for holding a volume of coolant, such as water. The coolant is recirculated and sprayed to entrain and cool any reactants that might have escaped from the reaction vessel. Baffles at the entrance to the chamber prevent the sprayed coolant from contacting the reaction vessel. An impact-absorbing layer is positioned between the vessel and the containment to at least partially absorb momentum of any fragments propelled by the rupturing vessel. Remote, quick-disconnecting fittings exterior to the containment, in cooperation with shut-off valves, enable the vessel to be isolated and the system safely taken off-line. Normally-closed orifices throughout the containment and chamber enable decontamination of interior surfaces when necessary. 2 figures.

Chastagner, P.

1994-07-05T23:59:59.000Z

27

Flexible Conversion Ratio Fast Reactor Systems Evaluation  

SciTech Connect (OSTI)

Conceptual designs of lead-cooled and liquid salt-cooled fast flexible conversion ratio reactors were developed. Both concepts have cores reated at 2400 MWt placed in a large-pool-type vessel with dual-free level, which also contains four intermediate heat exchanges coupling a primary coolant to a compact and efficient supercritical CO2 Brayton cycle power conversion system. Decay heat is removed passively using an enhanced Reactor Vessel Auxiliary Cooling System and a Passive Secondary Auxiliary Cooling System. The most important findings were that (1) it is feasible to design the lead-cooled and salt-cooled reactor with the flexible conversion ratio (CR) in the range of CR=0 and CR=1 n a manner that achieves inherent reactor shutdown in unprotected accidents, (2) the salt-cooled reactor requires Lithium thermal Expansion Modules to overcme the inherent salt coolant's large positive coolant temperature reactivity coefficient, (3) the preferable salt for fast spectrum high power density cores is NaCl-Kcl-MgCl2 as opposed to fluoride salts due to its better themal-hydraulic and neutronic characteristics, and (4) both reactor, but attain power density 3 times smaller than that of the sodium-cooled reactor.

Neil Todreas; Pavel Hejzlar

2008-06-30T23:59:59.000Z

28

LOSS-OF-COOLANT ACIDENT SIMULATIONS IN THE NATIONAL RESEARCH UNIVERSAL REACTOR  

SciTech Connect (OSTI)

Pressurized water reactor loss-of-coolant accident (LOCA) phenomena are being simulated with a series of experiments in the U-2 loop of the National Research Universal Reactor at Chalk River, Ontario, Canada. The first of these experiments includes up to 45 parametric thermal-hydraulic tests to establish the relationship among the reflood delay time of emergency coolant, the reflooding rate, and the resultant fuel rod cladding peak temperature. Subsequent experiments establish the fuel rod failure characteristics at selected peak cladding temperatures. Fuel rod cladding pressurization simulates high burnup fission gas pressure levels of modern PWRs. This document contains both an experiment overview of the LOCA simulation program and a review of the safety analyses performed by Pacific Northwest Laboratory (PNL) to define the expected operating conditions as well as to evaluate the worst case operating conditions. The primary intent of this document is to supply safety information required by the Chalk River Nuclear Laboratories (CRNL), to establish readiness to proceed from one test phase to the next and to establish the overall safety of the experiment. A hazards review summarizes safety issues, normal operation and three worst case accidents that have been addressed during the development of the experiment plan.

Bennett, W D; Goodman, R L; Heaberlin, S W; Hesson, G M; Nealley, C; Kirg, L L; Marshall, R K; McNair, G W; Meitzler, W D; Neally, G W; Parchen, L J; Pilger, J P; Rausch, W N; Russcher, G E; Schreiber, R E; Wildung, N J

1981-02-01T23:59:59.000Z

29

Moderator displacers for reducing coolant void reactivity in CANDU reactors: a neutronics scoping study.  

E-Print Network [OSTI]

??When the coolant is voided in a CANDU lattice, the net reactivity change is positive, due primarily to the fact that the coolant and moderator… (more)

Farkas, Robert

2014-01-01T23:59:59.000Z

30

Novel electromagnetic technique for repositioning of coolant tube spacers in CANDU nuclear reactors  

Science Journals Connector (OSTI)

A novel electromagnetic technique to reposition the coolant tube spacers in the fuel channels of CANDU nuclear reactors was successfully developed in the fall of 1983 at Ontario Hydro Research Division. The need to reposition dislocated spacers in noncommissioned reactors was discovered subsequent to the rupture of a pressure tube in one reactor at the Pickering Nuclear Generator Station in Ontario. A contributing factor to the failure of the tube was the fact that the annular spacers (garter springs) used to maintain the coaxial configuration between the pressure tube and its surrounding calandria tube had been displaced longitudinally for a number of years. Subsequent to this finding it was discovered that a number of garter springs in noncommissioned nuclear reactors were displaced due to vibration induced by various sources during the construction stage. Since the garter springs are not directly accessible by mechanical means extensive dismantling of the fuel channels would have been necessary to reposition the springs in their designated locations. This paper describes a novel method to reposition the garter springs without dismantling the fuel channels. The method consists of exerting a force on the springs in the direction of the required displacement by applying a large electromagnetic impulse (generated by a 200?kJ capacitor bank) to a drive coil inserted into the pressure tube opposite the spacer. The repositioning of displaced garter springs in five new reactors in Ontario has been carried out successfully in 1984. The saving in reactor repair cost interest charges and replacement energy cost was on the order of hundreds of millions of dollars. Equally large benefits and savings will be realized if the need to use this technique in commissioned reactors arises. Also the related development of strong compact coils and low?resistance pulse power cable have significant implications and advantages in various other applications related to the pulse power industry in general and to electromagnetic metal forming and fusion technologies specifically.

Joseph H. Dableh

1986-01-01T23:59:59.000Z

31

WWER Expert System for Fuel Failure Analysis Using Data on Primary Coolant Activity  

SciTech Connect (OSTI)

The computer expert system for fuel failure analysis of WWER during operation is presented. The diagnostics is based on the measurement of specific activity of reference nuclides in reactor primary coolant and application of a computer code for the data interpretation. The data analysis includes an evaluation of tramp uranium mass in reactor core, detection of failures by iodine and caesium spikes, evaluation of burnup of defective fuel. Evaluation of defective fuel burnup was carried out by applying the relation of caesium nuclides activity in spikes and relations of activities of gaseous fission products for steady state operational conditions. The method of burnup evaluation of defective fuel by use of fission gas activity is presented in detail. The neural-network analysis is performed for determination of failed fuel rod number and defect size. Results of the expert system application are illustrated for several fuel campaigns on operating WWER NPPs. (authors)

Likhanskii, V.V.; Evdokimov, I.A.; Sorokin, A.A.; Khromov, A.G.; Kanukova, V.D.; Apollonova, O.V. [SRC RF TRINITI, 142190, Troitsk, Moscow Reg. (Russian Federation); Ugryumov, A.V. [JSC TVEL, 119017, 24/26 Bolshaya Ordynka st., Moscow (Russian Federation)

2007-07-01T23:59:59.000Z

32

Self-actuating reactor shutdown system  

DOE Patents [OSTI]

A control system for the automatic or self-actuated shutdown or "scram" of a nuclear reactor. The system is capable of initiating scram insertion by a signal from the plant protection system or by independent action directly sensing reactor conditions of low-flow or over-power. Self-actuation due to a loss of reactor coolant flow results from a decrease of pressure differential between the upper and lower ends of an absorber element. When the force due to this differential falls below the weight of the element, the element will fall by gravitational force to scram the reactor. Self-actuation due to high neutron flux is accomplished via a valve controlled by an electromagnet and a thermionic diode. In a reactor over-power, the diode will be heated to a change of state causing the electromagnet to be shorted thereby actuating the valve which provides the changed flow and pressure conditions required for scramming the absorber element.

Barrus, Donald M. (San Jose, CA); Brummond, Willian A (Livermore, CA); Peterson, Leslie F. (Danville, CA)

1988-01-01T23:59:59.000Z

33

Nuclear reactor cooling system decontamination reagent regeneration  

DOE Patents [OSTI]

An improved method for decontaminating the coolant system of water-cooled nuclear power reactors and for regenerating the decontamination solution. A small amount of one or more weak-acid organic complexing agents is added to the reactor coolant, and the pH is adjusted to form a decontamination solution which is circulated throughout the coolant system to dissolve metal oxides from the interior surfaces and complex the resulting metal ions and radionuclide ions. The coolant containing the complexed metal ions and radionuclide ions is passed through a strong-base anion exchange resin bed which has been presaturated with a solution containing the complexing agents in the same ratio and having the same pH as the decontamination solution. As the decontamination solution passes through the resin bed, metal-complexed anions are exchanged for the metal-ion-free anions on the bed, while metal-ion-free anions in the solution pass through the bed, thus removing the metal ions and regenerating the decontamination solution.

Anstine, Larry D. (San Jose, CA); James, Dean B. (Saratoga, CA); Melaika, Edward A. (Berkeley, CA); Peterson, Jr., John P. (Livermore, CA)

1985-01-01T23:59:59.000Z

34

Nuclear reactor with makeup water assist from residual heat removal system  

DOE Patents [OSTI]

A pressurized water nuclear reactor uses its residual heat removal system to make up water in the reactor coolant circuit from an in-containment refueling water supply during staged depressurization leading up to passive emergency cooling by gravity feed from the refueling water storage tank, and flooding of the containment building. When depressurization commences due to inadvertence or a manageable leak, the residual heat removal system is activated manually and prevents flooding of the containment when such action is not necessary. Operation of the passive cooling system is not impaired. A high pressure makeup water storage tank is coupled to the reactor coolant circuit, holding makeup coolant at the operational pressure of the reactor. The staged depressurization system vents the coolant circuit to the containment, thus reducing the supply of makeup coolant. The level of makeup coolant can be sensed to trigger opening of successive depressurization conduits. The residual heat removal pumps move water from the refueling water storage tank into the coolant circuit as the coolant circuit is depressurized, preventing reaching the final depressurization stage unless the makeup coolant level continues to drop. The residual heat removal system can also be coupled in a loop with the refueling water supply tank, for an auxiliary heat removal path.

Corletti, Michael M. (New Kensington, PA); Schulz, Terry L. (Murrysville, PA)

1993-01-01T23:59:59.000Z

35

Assessment of the Use of Nitrogen Trifluoride for Purifying Coolant and Heat Transfer Salts in the Fluoride Salt-Cooled High-Temperature Reactor  

SciTech Connect (OSTI)

This report provides an assessment of the use of nitrogen trifluoride for removing oxide and water-caused contaminants in the fluoride salts that will be used as coolants in a molten salt cooled reactor.

Scheele, Randall D.; Casella, Andrew M.

2010-09-28T23:59:59.000Z

36

Improved vortex reactor system  

DOE Patents [OSTI]

An improved vortex reactor system for affecting fast pyrolysis of biomass and Refuse Derived Fuel (RDF) feed materials comprising: a vortex reactor having its axis vertically disposed in relation to a jet of a horizontally disposed steam ejector that impels feed materials from a feeder and solids from a recycle loop along with a motive gas into a top part of said reactor.

Diebold, James P. (Lakewood, CO); Scahill, John W. (Evergreen, CO)

1995-01-01T23:59:59.000Z

37

Engine coolant compatibility with the nonmetals found in automotive cooling systems  

SciTech Connect (OSTI)

High temperature, short term immersion testing was used to determine the impact of propylene and ethylene glycol base coolants on the physical properties of a variety of elastomeric and thermoplastic materials found in automotive cooling systems. The materials tested are typically used in cooling system hoses, radiator end tanks, and water pump seals. Traditional phosphate or borate-buffered silicated coolants as well as extended-life organic acid formulations were included. A modified ASTM protocol was used to carry out the testing both in the laboratory and at an independent testing facility. Post-test fluid chemistry including an analysis of any solids which may have formed is also reported. Coolant impact on elastomer integrity as well as elastomer-induced changes in fluid chemistry were found to be independent of the coolant`s glycol base.

Greaney, J.P.; Smith, R.A. [ARCO Chemical Co., Newtown Square, PA (United States)

1999-08-01T23:59:59.000Z

38

Reactor water cleanup system  

DOE Patents [OSTI]

A reactor water cleanup system includes a reactor pressure vessel containing a reactor core submerged in reactor water. First and second parallel cleanup trains are provided for extracting portions of the reactor water from the pressure vessel, cleaning the extracted water, and returning the cleaned water to the pressure vessel. Each of the cleanup trains includes a heat exchanger for cooling the reactor water, and a cleaner for cleaning the cooled reactor water. A return line is disposed between the cleaner and the pressure vessel for channeling the cleaned water thereto in a first mode of operation. A portion of the cooled water is bypassed around the cleaner during a second mode of operation and returned through the pressure vessel for shutdown cooling.

Gluntz, Douglas M. (San Jose, CA); Taft, William E. (Los Gatos, CA)

1994-01-01T23:59:59.000Z

39

Reactor water cleanup system  

DOE Patents [OSTI]

A reactor water cleanup system includes a reactor pressure vessel containing a reactor core submerged in reactor water. First and second parallel cleanup trains are provided for extracting portions of the reactor water from the pressure vessel, cleaning the extracted water, and returning the cleaned water to the pressure vessel. Each of the cleanup trains includes a heat exchanger for cooling the reactor water, and a cleaner for cleaning the cooled reactor water. A return line is disposed between the cleaner and the pressure vessel for channeling the cleaned water thereto in a first mode of operation. A portion of the cooled water is bypassed around the cleaner during a second mode of operation and returned through the pressure vessel for shutdown cooling. 1 figure.

Gluntz, D.M.; Taft, W.E.

1994-12-20T23:59:59.000Z

40

Mitigation of steam generator tube rupture in a pressurized water reactor with passive safety systems  

DOE Patents [OSTI]

The effects of steam generator tube ruptures in a pressurized water reactor are mitigated by reducing the pressure in the primary loop by diverting reactor coolant through the heat exchanger of a passive heat removal system immersed in the in containment refueling water storage tank in response to a high feed water level in the steam generator. Reactor coolant inventory is maintained by also in response to high steam generator level introducing coolant into the primary loop from core make-up tanks at the pressure in the reactor coolant system pressurizer. The high steam generator level is also used to isolate the start-up feed water system and the chemical and volume control system to prevent flooding into the steam header. 2 figures.

McDermott, D.J.; Schrader, K.J.; Schulz, T.L.

1994-05-03T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Mitigation of steam generator tube rupture in a pressurized water reactor with passive safety systems  

DOE Patents [OSTI]

The effects of steam generator tube ruptures in a pressurized water reactor are mitigated by reducing the pressure in the primary loop by diverting reactor coolant through the heat exchanger of a passive heat removal system immersed in the in containment refueling water storage tank in response to a high feed water level in the steam generator. Reactor coolant inventory is maintained by also in response to high steam generator level introducing coolant into the primary loop from core make-up tanks at the pressure in the reactor coolant system pressurizer. The high steam generator level is also used to isolate the start-up feed water system and the chemical and volume control system to prevent flooding into the steam header. 2 figures.

McDermott, Daniel J. (Export, PA); Schrader, Kenneth J. (Penn Hills, PA); Schulz, Terry L. (Murrysville Boro, PA)

1994-01-01T23:59:59.000Z

42

Improved vortex reactor system  

DOE Patents [OSTI]

An improved vortex reactor system is described for affecting fast pyrolysis of biomass and Refuse Derived Fuel (RDF) feed materials comprising: a vortex reactor having its axis vertically disposed in relation to a jet of a horizontally disposed steam ejector that impels feed materials from a feeder and solids from a recycle loop along with a motive gas into a top part of said reactor. 12 figs.

Diebold, J.P.; Scahill, J.W.

1995-05-09T23:59:59.000Z

43

Dysprosium as a resonance absorber and its effect on the coolant void reactivity in Advanced Heavy Water Reactor (AHWR)  

Science Journals Connector (OSTI)

Dysprosium has been used as a slow neutron absorber in the fuel assembly of Advanced Heavy Water Reactor (AHWR) to achieve a negative coolant void reactivity. Dysprosium as occurring in nature has as many as seven isotopes namely, 156Dy, 158Dy, 160Dy, 161Dy, 162Dy, 163Dy, and 164Dy. Of these, the isotope 164Dy has the largest absorption cross section for thermal neutrons. In the past, nuclear data libraries used in our studies have considered only 164Dy isotope and this was sufficient for performing foil activation studies of Dy. The other isotopes of Dy have significant resonances and could affect the design. The treatment of the dysprosium isotopes with resonance tabulations is required for a more accurate estimation of the lattice characteristics like the coolant void reactivity. The use of resonance tabulations for the dysprosium isotopes and its effect on the coolant void reactivity of AHWR fuel cluster has been studied in this paper. Also, the treatment of the stand-alone structural rod with dysprosium as burnable absorber having resonance tabulations has been done for the first time.

Umasankari Kannan; S. Ganesan

2010-01-01T23:59:59.000Z

44

Reactor & Nuclear Systems Publications | ORNL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Nuclear Science Home | Science & Discovery | Nuclear Science | Publications and Reports | Reactor and Nuclear Systems Publications SHARE Reactor and Nuclear Systems Publications...

45

Experiment Operations Plan for a Loss-of-Coolant Accident Simulation in the National Research Universal Reactor Materials Tests 1 and 2  

SciTech Connect (OSTI)

A loss of Coolant Accident (LOCA) simulation program is evaluating the thermal-hydraulic and mechanical effects of LOCA conditions on pressurized water reactor test fuel bundles. This experiment operation plan for the second and third experiments of the program will provide peak fuel cladding temperatures of up to 1172K (1650{degree}F) and 1061K (1450{degree}) respectively. for a long enough time to cause test fuel cladding deformation and rupture in both. Reflood coolant delay times and the reflooding rates for the experiments were selected from thermal-hydraulic data measured in the National Research Universal (NRU) reactor facilities and test train assembly during the first experiment.

Russcher, G. E.; Wilson, C. L.; Marshall, R, K.; King, L. L.; Parchen, L. J.; Pilger, J. P.; Hesson, G. M.; Mohr, C. L.

1981-09-01T23:59:59.000Z

46

On-Line Coolant Chemistry Analysis  

SciTech Connect (OSTI)

Impurities in the gas coolant of the space nuclear power plant (SNPP) can provide valuable indications of problems in the reactor and an overall view of system health. By monitoring the types and amounts of these impurities, much can be implied regarding the status of the reactor plant. However, a preliminary understanding of the expected impurities is important before evaluating prospective detection and monitoring systems. Currently, a spectroscopy system is judged to hold the greatest promise for monitoring the impurities of interest in the coolant because it minimizes the number of entry and exit points to the plant and provides the ability to detect impurities down to the 1 ppm level.

LM Bachman

2006-07-19T23:59:59.000Z

47

A passively-safe fusion reactor blanket with helium coolant and steel structure  

SciTech Connect (OSTI)

Helium is attractive for use as a fusion blanket coolant for a number of reasons. It is neutronically and chemically inert, nonmagnetic, and will not change phase during any off-normal or accident condition. A significant disadvantage of helium, however, is its low density and volumetric heat capacity. This disadvantage manifests itself most clearly during undercooling accident conditions such as a loss of coolant accident (LOCA) or a loss of flow accident (LOFA). This thesis describes a new helium-cooled tritium breeding blanket concept which performs significantly better during such accidents than current designs. The proposed blanket uses reduced-activation ferritic steel as a structural material and is designed for neutron wall loads exceeding 4 MW/m{sup 2}. The proposed geometry is based on the nested-shell concept developed by Wong, but some novel features are used to reduce the severity of the first wall temperature excursion. These features include the following: (1) A ``beryllium-joint`` concept is introduced, which allows solid beryllium slabs to be used as a thermal conduction path from the first wall to the cooler portions of the blanket. The joint concept allows for significant swelling of the beryllium (10 percent or more) without developing large stresses in the blanket structure. (2) Natural circulation of the coolant in the water-cooled shield is used to maintain shield temperatures below 100 degrees C, thus maintaining a heat sink close to the blanket during the accident. This ensures the long-term passive safety of the blanket.

Crosswait, K.M.

1994-04-01T23:59:59.000Z

48

Safety Design Strategy for the Advanced Test Reactor Primary Coolant Pump and Motor Replacement Project  

SciTech Connect (OSTI)

In accordance with the requirements of U.S. Department of Energy (DOE) Order 413.3B, “Program and Project Management for the Acquisition of Capital Assets,” safety must be integrated into the design process for new or major modifications to DOE Hazard Category 1, 2, and 3 nuclear facilities. The intended purpose of this requirement involves the handling of hazardous materials, both radiological and chemical, in a way that provides adequate protection to the public, workers, and the environment. Requirements provided in DOE Order 413.3B and DOE Order 420.1B, “Facility Safety,” and the expectations of DOE-STD-1189-2008, “Integration of Safety into the Design Process,” provide for identification of hazards early in the project and use of an integrated team approach to design safety into the facility. This safety design strategy provides the basic safety-in-design principles and concepts that will be used for the Advanced Test Reactor Reliability Sustainment Project. While this project does not introduce new hazards to the ATR, it has the potential for significant impacts to safety-related systems, structures, and components that are credited in the ATR safety basis and are being replaced. Thus the project has been determined to meet the definition of a major modification and is being managed accordingly.

Noel Duckwitz

2011-06-01T23:59:59.000Z

49

Review of experiments to evaluate the ability of electrical heater rods to simulate nuclear fuel rod behavior during postulated loss-of-coolant accidents in light water reactors  

SciTech Connect (OSTI)

Issues related to using electrical fuel rod simulators to simulate nuclear fuel rod behavior during postulated loss-of-coolant accident (LOCA) conditions in light water reactors are summarized. Experimental programs which will provide a data base for comparing electrical heater rod and nuclear fuel rod LOCA responses are reviewed.

McPherson, G D; Tolman, E L

1980-01-01T23:59:59.000Z

50

Design of a 25-kWe Surface Reactor System Based on SNAP Reactor Technologies  

SciTech Connect (OSTI)

A Hastelloy-X clad, sodium-potassium (NaK-78) cooled, moderated spectrum reactor using uranium zirconium hydride (UZrH) fuel based on the SNAP program reactors is a promising design for use in surface power systems. This paper presents a 98 kWth reactor for a power system the uses multiple Stirling engines to produce 25 kWe-net for 5 years. The design utilizes a pin type geometry containing UZrHx fuel clad with Hastelloy-X and NaK-78 flowing around the pins as coolant. A compelling feature of this design is its use of 49.9% enriched U, allowing it to be classified as a category III-D attractiveness and reducing facility costs relative to highly-enriched space reactor concepts. Presented below are both the design and an analysis of this reactor's criticality under various safety and operations scenarios.

Dixon, David D. [Nuclear Systems Design Group, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Department of Nuclear Engineering, North Carolina State University, Raleigh, NC 27695 (United States); Hiatt, Matthew T. [Nuclear Systems Design Group, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Department of Nuclear Engineering, Texas A and M University, College Station, TX 77843 (United States); Poston, David I.; Kapernick, Richard J. [Nuclear Systems Design Group, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

2006-01-20T23:59:59.000Z

51

Modification of the Core Cooling System of TRIGA 2000 Reactor  

SciTech Connect (OSTI)

To accomplish safety requirements, a set of actions has to be performed following the recommendations of the IAEA safety series 35 applied to research reactor. Such actions are considered in modernization of the old system, improving the core cooling system and safety evaluations. Due to the complexity of the process and the difficulty in putting the apparatus in the reactor core, analytical and experimental study on the determination of flow and temperature distribution in the whole coolant channel are difficult to be done. In the present work, a numerical study of flow and temperature distribution in the coolant channel of TRIGA 2000 has been carried out using CFD package. For this study, simulations were carried out on 3-D tested model. The model consists of the reactor tank, thermal and thermalizing column, reflector, rotary specimen rack, chimney, fuel element, primary pipe, diffuser, beam tube and a part of the core are constructed by 1.50 million unstructured tetrahedral cell elements. The results show that for the initial condition (116 fuel elements in the core) and for the inlet temperature of 24 deg. C and the primary velocity of 5.6 m/s, there no boiling phenomena occur in the coolant channel. Due to this result, it is now possible to improve the core cooling system of TRIGA 2000 reactor. Meanwhile, forced flow from the diffuser system only affected the flow pattern in the outside of chimney and put on a small effect to the fluid flow's velocity in the inside of chimney.

Umar, Efrizon; Fiantini, Rosalina [National Nuclear Energy Agency of Indonesia, Jalan Tamansari 71, Bandung, 40132 (Indonesia)

2010-06-22T23:59:59.000Z

52

Polonium release from an ATW burner system with liquid lead-bismuth coolant  

SciTech Connect (OSTI)

The authors analyzed polonium release hazards in a conceptual pool-type ATW burner with liquid lead-bismuth eutectic (LBE) coolant. Simplified quantitative models are used based on experiments and real NPP experience. They found little Po contamination outside the burner under normal operating conditions with nominal leakage from the gas system. In sudden gas leak and/or coolant spill accidents, the P contamination level can reach above the regulation limit but short exposure would not lead to severe health consequences. They are evaluating and developing mitigation methods.

Li, N. [Los Alamos National Lab., NM (United States); Yefimov, E.; Pankratov, D. [Inst. of Physics and Power Engineering, Obninsk (Russian Federation)

1998-04-01T23:59:59.000Z

53

Large break loss of coolant severe accident sequences at the HFIR (High Flux Isotope Reactor)  

SciTech Connect (OSTI)

An assessment of many potential HFIR severe accident phenomena was conducted during the HFIR design effort, and many severe accident mitigating features were designed into the plant. These evaluation typically incorporated a bounding'' or highly conservative analysis approach and employed tools and techniques representative of the state of knowledge in the mid-1960s. Recently, programs to address severe accident issues were initiated at the Oak Ridge National Laboratory (ORNL) to support the HFIR probabilistic risk assessment (PRA) and equipment qualification and accident management studies. This paper presents the results of environment condition calculations conducted to evaluate a response of HFIR's heat exchanger cell environment to a double-ended rupture of a 0.25 m diameter coolant loop downstream of the circulating pump and check valve. The confinement calculations were performed using an atmospheric fission product source for the heat exchanger cell consistent with, but more conservative than that stipulated in Regulatory Guide 1.89. The results of the calculations indicate that the heat exchanger cell atmospheric temperature peaks at 377 K 225 seconds into the transient and then begins decreasing at approximately 1.7 K per minute. 8 refs., 5 figs.

Simpson, D.B.; Greene, S.R.

1990-01-01T23:59:59.000Z

54

Fusion reactor systems  

Science Journals Connector (OSTI)

In this review we consider deuterium-tritium (D-T) fusion reactors based on four different plasma-confinement and heating approaches: the tokamak, the theta-pinch, the magnetic-mirror, and the laser-pellet system. We begin with a discussion of the dynamics of reacting plasmas and basic considerations of reactor power balance. The essential plasma physical aspects of each system are summarized, and the main characteristics of the corresponding conceptual power plants are described. In tokamak reactors the plasma densities are about 1020 m-3, and the ? values (ratio of plasma pressure to confining magnetic pressure) are approximately 5%. Plasma burning times are of the order of 100-1000 sec. Large superconducting dc magnets furnish the toroidal magnetic field, and 2-m thick blankets and shields prevent heat deposition in the superconductor. Radially diffusing plasma is diverted away from the first wall by means of null singularities in the poloidal (or transverse) component of the confining magnetic field. The toroidal theta-pinch reactor has a much smaller minor diameter and a much larger major diameter, and operates on a 10-sec cycle with 0.1-sec burning pulses. It utilizes shock heating from high-voltage sources and adabatic-compression heating powered by low-voltage, pulsed cryogenic magnetic or inertial energy stores, outside the reactor core. The plasma has a density of about 1022 m-3 and ? values of nearly unity. In the power balance of the reactor, direct-conversion energy obtained by expansion of the burning high-? plasma against the containing magnetic field is an important factor. No divertor is necessary since neutral-gas flow cools and replaces the "spent" plasma between pulses. The open-ended mirror reactor uses both thermal conversion of neutron energy and direct conversion of end-loss plasma energy to dc electrical power. A fraction of this direct-convertor power is then fed back to the ioninjection system to sustain the reaction and maintain the plasma. The average ion energy is 600 keV, plasma diameter 6 m, and the plasma beta 85%. The power levels of the three magnetic-confinement devices are in the 500-2000 MWe range, with the exception of the mirror reactor, for which the output is approximately 200 MWe. In Laser-Pellet reactors, frozen D-T pellets are ignited in a cavity which absorbs the electromagnetic, charged particle, and neutron energy from the fusion reaction. The confinement is "inertial," since the fusion reaction occurs during the disassembly of the heated pellet. A pellet-cavity unit would produce about 200 MWt in pulses with a repetition rate of the order of 10 sec-1. Such units could be clustered to give power plants with outputs in the range of 1000 MWe.

F. L. Ribe

1975-01-01T23:59:59.000Z

55

Nuclear reactor cooling system decontamination reagent regeneration. [PWR; BWR  

DOE Patents [OSTI]

An improved method for decontaminating the coolant system of water-cooled nuclear power reactors and for regenerating the decontamination solution is described. A small amount of one or more weak-acid organic complexing agents is added to the reactor coolant, and the pH is adjusted to form a decontamination solution which is circulated throughout the coolant system to dissolve metal oxides from the interior surfaces and complex the resulting metal ions and radionuclide ions. The coolant containing the complexed metal ions and radionuclide ions is passed through a strong-base anion exchange resin bed which has been presaturated with a solution containing the complexing agents in the same ratio and having the same pH as the decontamination solution. As the decontamination solution passes through the resin bed, metal-complexed anions are exchanged for the metal-ion-free anions on the bed, while metal-ion-free anions in the solution pass through the bed, thus removing the metal ions and regenerating the decontamination solution.

Anstine, L.D.; James, D.B.; Melaika, E.A.; Peterson, J.P. Jr.

1980-06-06T23:59:59.000Z

56

Experimental Investigation on the Effects of Coolant Concentration on Sub-Cooled Boiling and Crud Deposition on Reactor Cladding at Prototypical PWR Operating Conditions  

SciTech Connect (OSTI)

Increasing demand for energy necessitates nuclear power units to increase power limits. This implies significant changes in the design of the core of the nuclear power units, therefore providing better performance and safety in operations. A major hindrance to the increase of nuclear reactor performance especially in Pressurized Deionized water Reactors (PWR) is Axial Offset Anomaly (AOA)--the unexpected change in the core axial power distribution during operation from the predicted distribution. This problem is thought to be occur because of precipitation and deposition of lithiated compounds like boric acid (H{sub 2}BO{sub 3}) and lithium metaborate (LiBO{sub 2}) on the fuel rod cladding. Deposited boron absorbs neutrons thereby affecting the total power distribution inside the reactor. AOA is thought to occur when there is sufficient build-up of crud deposits on the cladding during subcooled nucleate boiling. Predicting AOA is difficult as there is very little information regarding the heat and mass transfer during subcooled nucleate boiling. An experimental investigation was conducted to study the heat transfer characteristics during subcooled nucleate boiling at prototypical PWR conditions. Pool boiling tests were conducted with varying concentrations of lithium metaborate (LiBO{sub 2}) and boric acid (H{sub 2}BO{sub 3}) solutions in deionized water. The experimental data collected includes the effect of coolant concentration, subcooling, system pressure and heat flux on pool the boiling heat transfer coefficient. The analysis of particulate deposits formed on the fuel cladding surface during subcooled nucleate boiling was also performed. The results indicate that the pool boiling heat transfer coefficient degrades in the presence of boric acid and lithium metaborate compared to pure deionized water due to lesser nucleation. The pool boiling heat transfer coefficients decreased by about 24% for 5000 ppm concentrated boric acid solution and by 27% for 5000 ppm lithium metaborate solution respectively at the saturation temperature for 1000 psi (68.9 bar) coolant pressure. Boiling tests also revealed the formation of fine deposits of boron and lithium on the cladding surface which degraded the heat transfer rates. The boron and lithium metaborate precipitates after a 5 day test at 5000 ppm concentration and 1000 psi (68.9 bar) operating pressure reduced the heat transfer rate 21% and 30%, respectively for the two solutions.

Schultis, J., Kenneth; Fenton, Donald, L.

2006-10-20T23:59:59.000Z

57

Experiment Operations Plan for a Loss-of-Coolant Accident Simulation in the National Research Universal Reactor Materials Test 2  

SciTech Connect (OSTI)

A loss-of-coolant accident (LOCA) simulation program is evaluating the thermal-hydraulic and mechanical effects on pressurized water reactor (PWR) test fuel bundles. This Experiment Operation Plan (EOP) Addendum 2, together with the referenced EOP, describes the desired operating conditions and additional hazards review associated with the four-part MT-2 experiment. The primary portions of the experiment, MT-2.2 and MT-2.3, will evaluate the following: 1) the mechanical deformation of pressurized fuel rods subjected to a slow LOCA, using reflood water for temperature control, that is designed to produce cladding temperatures in the range from 1033 to 1089K (1400 to 1500°F) for an extended time, and 2) the effects of the deformed and possibly failed cladding on the thermal-hydraulic performance of the test assembly during simulated LOCA heating and reflooding. The secondary portions of the experiment, MT-2.1 and MT-2.4, are intended to provide thermal-hydraulic calibration information during two-stage reflood conditions for 1) relatively low cladding temperatures, <839K (1050°F), on nondeformed rods, and 2) moderately high cladding temperatures, <1089K (1500°F), on deformed rods.

Russcher, G. E.; Barner, J. O.; Hesson, G. M.; Wilson, C. L.; Parchen, L. J.; Cunningham, M. E.; Marshall, R. K.; Mohr, C. L.

1981-09-01T23:59:59.000Z

58

Chimney for enhancing flow of coolant water in natural circulation boiling water reactor  

DOE Patents [OSTI]

A chimney which can be reconfigured or removed during refueling to allow vertical removal of the fuel assemblies is disclosed. The chimney is designed to be collapsed or dismantled. Collapse or dismantlement of the chimney reduces the volume required for chimney storage during the refueling operation. Alternatively, the chimney has movable parts which allow reconfiguration of its structure. In a first configuration suitable for normal reactor operation, the chimney is radially constricted such that the chimney obstructs vertical removal of the fuel assemblies. In a second configuration suitable for refueling or maintenance of the fuel core, the parts of the chimney which obstruct access to the fuel assemblies are moved radially outward to positions whereas access to the fuel assemblies is not obstructed. 11 figs.

Oosterkamp, W.J.; Marquino, W.

1999-01-05T23:59:59.000Z

59

Advanced nuclear reactor safety analysis: the simulation of a small break loss of coolant accident in the simplified boiling water reactor using RELAP5/MOD3.1.1  

E-Print Network [OSTI]

The thermal hydraulic simulation code RELAP5/MOD3.1.1 was utilized to model General Electric's Simplified Boiling Water Reactor plant. The model of the plant was subjected to a small break loss of coolant accident occurring from a guillotine shear...

Faust, Christophor Randall

1995-01-01T23:59:59.000Z

60

Attrition reactor system  

DOE Patents [OSTI]

A reactor vessel for reacting a solid particulate with a liquid reactant has a centrifugal pump in circulatory flow communication with the reactor vessel for providing particulate attrition, resulting in additional fresh surface where the reaction can occur. 2 figures.

Scott, C.D.; Davison, B.H.

1993-09-28T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Lamp system with conditioned water coolant and diffuse reflector of polytetrafluorethylene(PTFE)  

DOE Patents [OSTI]

A lamp system with a very soft high-intensity output is provided over a large area by water cooling a long-arc lamp inside a diffuse reflector of polytetrafluorethylene (PTFE) and titanium dioxide (TiO.sub.2) white pigment. The water is kept clean and pure by a one micron particulate filter and an activated charcoal/ultraviolet irradiation system that circulates and de-ionizes and biologically sterilizes the coolant water at all times, even when the long-arc lamp is off.

Zapata, Luis E. (Livermore, CA); Hackel, Lloyd (Livermore, CA)

1999-01-01T23:59:59.000Z

62

Prospects for and problems of using light-water supercritical-pressure coolant in nuclear reactors in order to increase the efficiency of the nuclear fuel cycle  

SciTech Connect (OSTI)

Trends in the development of the power sector of the Russian and world power industries both at present time and in the near future are analyzed. Trends in the rise of prices for reserves of fossil and nuclear fuels used for electricity production are compared. An analysis of the competitiveness of electricity production at nuclear power plants as compared to the competitiveness of electricity produced at coal-fired and natural-gas-fired thermal power plants is performed. The efficiency of the open nuclear fuel cycle and various versions of the closed nuclear fuel cycle is discussed. The requirements on light-water reactors under the scenario of dynamic development of the nuclear power industry in Russia are determined. Results of analyzing the efficiency of fuel utilization for various versions of vessel-type light-water reactors with supercritical coolant are given. Advantages and problems of reactors with supercritical-pressure water are listed.

Alekseev, P. N.; Semchenkov, Yu. M.; Sedov, A. A., E-mail: sedov@dhtp.kial.ru; Subbotin, S. A.; Chibinyaev, A. V. [Russian Research Centre Kurchatov Institute (Russian Federation)

2011-12-15T23:59:59.000Z

63

Combined cooling and purification system for nuclear reactor spent fuel pit, refueling cavity, and refueling water storage tank  

DOE Patents [OSTI]

The spent fuel pit of a pressured water reactor (PWR) nuclear power plant has sufficient coolant capacity that a safety rated cooling system is not required. A non-safety rated combined cooling and purification system with redundant branches selectively provides simultaneously cooling and purification for the spent fuel pit, the refueling cavity, and the refueling water storage tank, and transfers coolant from the refueling water storage tank to the refueling cavity without it passing through the reactor core. Skimmers on the suction piping of the combined cooling and purification system eliminate the need for separate skimmer circuits with dedicated pumps.

Corletti, Michael M. (New Kensington, PA); Lau, Louis K. (Monroeville, PA); Schulz, Terry L. (Murrysville Boro, PA)

1993-01-01T23:59:59.000Z

64

Solvent refined coal reactor quench system  

DOE Patents [OSTI]

There is described an improved SRC reactor quench system using a condensed product which is recycled to the reactor and provides cooling by evaporation. In the process, the second and subsequent reactors of a series of reactors are cooled by the addition of a light oil fraction which provides cooling by evaporation in the reactor. The vaporized quench liquid is recondensed from the reactor outlet vapor stream. 1 fig.

Thorogood, R.M.

1983-11-08T23:59:59.000Z

65

Rapid starting methanol reactor system  

DOE Patents [OSTI]

The invention relates to a methanol-to-hydrogen cracking reactor for use with a fuel cell vehicular power plant. The system is particularly designed for rapid start-up of the catalytic methanol cracking reactor after an extended shut-down period, i.e., after the vehicular fuel cell power plant has been inoperative overnight. Rapid system start-up is accomplished by a combination of direct and indirect heating of the cracking catalyst. Initially, liquid methanol is burned with a stoichiometric or slightly lean air mixture in the combustion chamber of the reactor assembly. The hot combustion gas travels down a flue gas chamber in heat exchange relationship with the catalytic cracking chamber transferring heat across the catalyst chamber wall to heat the catalyst indirectly. The combustion gas is then diverted back through the catalyst bed to heat the catalyst pellets directly. When the cracking reactor temperature reaches operating temperature, methanol combustion is stopped and a hot gas valve is switched to route the flue gas overboard, with methanol being fed directly to the catalytic cracking reactor. Thereafter, the burner operates on excess hydrogen from the fuel cells.

Chludzinski, Paul J. (38 Berkshire St., Swampscott, MA 01907); Dantowitz, Philip (39 Nancy Ave., Peabody, MA 01960); McElroy, James F. (12 Old Cart Rd., Hamilton, MA 01936)

1984-01-01T23:59:59.000Z

66

High Flux Isotope Reactor system RELAP5 input model  

SciTech Connect (OSTI)

A thermal-hydraulic computational model of the High Flux Isotope Reactor (HFIR) has been developed using the RELAP5 program. The purpose of the model is to provide a state-of-the art thermal-hydraulic simulation tool for analyzing selected hypothetical accident scenarios for a revised HFIR Safety Analysis Report (SAR). The model includes (1) a detailed representation of the reactor core and other vessel components, (2) three heat exchanger/pump cells, (3) pressurizing pumps and letdown valves, and (4) secondary coolant system (with less detail than the primary system). Data from HFIR operation, component tests, tests in facility mockups and the HFIR, HFIR specific experiments, and other pertinent experiments performed independent of HFIR were used to construct the model and validate it to the extent permitted by the data. The detailed version of the model has been used to simulate loss-of-coolant accidents (LOCAs), while the abbreviated version has been developed for the operational transients that allow use of a less detailed nodalization. Analysis of station blackout with core long-term decay heat removal via natural convection has been performed using the core and vessel portions of the detailed model.

Morris, D.G.; Wendel, M.W.

1993-01-01T23:59:59.000Z

67

Effects of turbulence model on convective heat transfer of coolant flow in a prismatic very high temperature reactor core  

SciTech Connect (OSTI)

The existing study of Spall et al. shows that only {nu}{sup 2}-f turbulence model well matches with the experimental data of Shehata and McEligot which were obtained under strongly heated gas flows. Significant over-predictions in those literatures were observed in the convective heat transfer with the other famous turbulence models such as the k-{epsilon} and k-{omega} models. In spite of such good evidence about the performance of the{nu}{sup 2}-f model, the application of the {nu}{sup 2}-f model to the thermo-fluid analysis of a prismatic core is very rare. In this paper, therefore, the convective heat transfer of the coolant flow in a prismatic core has been investigated using the {nu}{sup 2}-f model. Computational fluid dynamics (CFD) calculations have been carried out for the typical unit cell geometry of a prismatic fuel column with typical operating conditions of prismatic designs. The tested Reynolds numbers of the coolant flow are 10,000, 20,000, 30,000 and 50,000. The predicted Nusselt numbers with the {nu}{sup 2}-f model are compared with the results by the other turbulence models (k-{epsilon} and SST) as well as the empirical correlations. (authors)

Lee, S. N.; Tak, N. I.; Kim, M. H.; Noh, J. M. [Korea Atomic Energy Research Inst., Daedeok-daero 989-11, Yuseong-gu, Daejeon (Korea, Republic of)

2012-07-01T23:59:59.000Z

68

16N ?-Ray Diagnostics of a Nuclear Reactor in a Nuclear Power Plant  

Science Journals Connector (OSTI)

The AIRM system, which uses the 16N activity in the VVÉR-1000 reactor at the Kalinin nuclear power plant to measure the thermal power of the reactor and the coolant flow rate, and similar systems used in nuclear

S. G. Tsypin; V. V. Lysenko; A. I. Musorin; L. N. Bogachek; V. F. Bai…

2003-09-01T23:59:59.000Z

69

Reactor vessel annealing system  

DOE Patents [OSTI]

A system for annealing a vessel (14) in situ by heating the vessel (14) to a defined temperature, composed of: an electrically operated heater assembly (10) insertable into the vessel (14) for heating the vessel (14) to the defined temperature; temperature monitoring components positioned relative to the heater assembly (10) for monitoring the temperature of the vessel (14); a controllable electric power supply unit (32-60) for supplying electric power required by the heater assembly (10); a control unit (80-86) for controlling the power supplied by the power supply unit (32-60); a first vehicle (2) containing the power supply unit (32-60); a second vehicle (4) containing the control unit (80-86); power conductors (18,22) connectable between the power supply unit (32-60) and the heater unit (10) for delivering the power supplied by the power supply unit (32-60) to the heater assembly (10); signal conductors (20,24) connectable between the temperature monitoring components and the control unit (80-86) for delivering temperature indicating signals from the temperature monitoring components to the control unit (80-86); and control conductors (8) connectable between the control unit (80-86) and the power supply unit (32-60) for delivering to the power supply unit (32-60) control signals for controlling the level of power supplied by the power supply unit (32-60) to the heater assembly (10).

Miller, Phillip E. (Greensburg, PA); Katz, Leonoard R. (Pittsburgh, PA); Nath, Raymond J. (Murrysville, PA); Blaushild, Ronald M. (Export, PA); Tatch, Michael D. (Randolph, NJ); Kordalski, Frank J. (White Oak, PA); Wykstra, Donald T. (Pittsburgh, PA); Kavalkovich, William M. (Monroeville, PA)

1991-01-01T23:59:59.000Z

70

Reactor and Nuclear Systems Division (RNSD)  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

RNSD Home RNSD Home Research Groups Advanced Reactor Systems & Safety Nuclear Data & Criticality Safety Nuclear Security Modeling Radiation Safety Information Computational Center Radiation Transport Reactor Physics Thermal Hydraulics & Irradiation Engineering Used Fuel Systems Staff Details (CV/Bios) Publications Org Chart Contact Us ORNL Staff Only Research Groups Advanced Reactor Systems & Safety Nuclear Data & Criticality Safety Nuclear Security Modeling Radiation Safety Information Computational Center Radiation Transport Reactor Physics Thermal Hydraulics & Irradiation Engineering Used Fuel Systems Reactor and Nuclear Systems Division News Highlights U.S. Rep. Fleischmann touts ORNL as national energy treasure Martin Peng wins Fusion Power Associates Leadership Award

71

Review and evaluation of the RELAP5YA computer code and the Vermont Yankee LOCA (Loss-of-Coolant Accident) licensing analysis model for use in small and large break BWR (Boiling Water Reactor) LOCAS  

SciTech Connect (OSTI)

A review has been completed of the RELAP5YA computer code to determine its acceptability for performing licensing analyses. The review was limited to Boiling Water Reactor (BWR) reactor applications. In addition, a Loss-Of-Coolant Accident (LOCA) licensing analysis method, using the RELAP5YA computer code, has been reviewed. This method is applicable to the Vermont Yankee Nuclear Power Station to perform full break spectra LOCA and fuel cycle independent analyses. The review of the RELAP5YA code consisted of an evaluation of all Yankee Atomic Electric Company (YAEC) incorporated modifications to the RELAP5/MOD1 Cycle 18 computer code from which the licensing version of the code originated. Qualifying separate and integral effects assessment calculations were reviewed to evaluate the validity and proper implementation of the various added models. The LOCA licensing method was assessed by reviewing two RELAP5YA system input models and evaluating several small and large break qualifying transient calculations. A review of the RELAP5YA code modifications and their assessments, as well as the submitted LOCA licensing method, is given and the results of the review are provided.

Jones, J.L.

1987-01-01T23:59:59.000Z

72

Fuel-Coolant-Interaction modeling and analysis work for the High Flux Isotope Reactor Safety Analysis Report  

SciTech Connect (OSTI)

A brief historical background and a description of short- and long-term task plan development for effective closure of this important safety issue for the HFIR are given. Short-term aspects deal with Fuel-Coolant-Interaction (FCI) issues experimentation, modeling, and analysis for the flow-blockage-induced steam explosion events in direct support of the SAR. Long-term aspects deal with addressing FCI issues resulting from other accidents in conjunction with issues dealing with aluminum ignition, which can result in an order of magnitude increase in overall energetics. Problem formulation, modeling, and computer code simulation for the various phases of steam explosions are described. The evaluation of core melt initiation propagation, and melt superheat are described. Core melt initiation and propagation have been studied using simple conservative models as well as from modeling and analysis using RELAP5. Core debris coolability, heatup, and melting/freezing aspects have been studied by use of the two-dimensional melting/freezing analysis code 2DKO, which was also benchmarked with MELCOR code predictions. Descriptions are provided for the HM, BH, FCIMOD, and CTH computer codes that have been implemented for studying steam explosion energetics from the standpoint of evaluating bounding loads by thermodynamic models or best-estimate loads from one- and two-dimensional simulations of steam explosion energetics. Vessel failure modeling and analysis was conducted using the principles of probabilistic fracture mechanics in conjunction with ADINA code calculations. Top head bolts failure modeling has also been conducted where the failure criterion was based upon stresses in the bolts exceeding the material yield stress for a given time duration. Missile transport modeling and analysis was conducted by setting up a one-dimensional mathematical model that accounts for viscous dissipation, virtual mass effects, and material inertia.

Taleyarkhan, R.P.; Georgevich, V.; Nestor, C.W.; Chang, S.J.; Freels, J.; Gat, U.; Lepard, B.L.; Gwaltney, R.C.; Luttrell, C.; Kirkpatrick, J.

1993-07-01T23:59:59.000Z

73

Shutdown system for a nuclear reactor  

DOE Patents [OSTI]

An ultimate shutdown system is provided for termination of neutronic activity in a nuclear reactor. The shutdown system includes bead chains comprising spherical containers suspended on a flexible cable. The containers are comprised of mating hemispherical shells which provide a ruggedized enclosure for reactor poison material. The bead chains, normally suspended above the reactor core on storage spools, are released for downward travel upon command from an external reactor monitor. The chains are capable of horizontal movement, so as to flow around obstructions in the reactor during their downward motion.

Groh, Edward F. (Naperville, IL); Olson, Arne P. (Western Springs, IL); Wade, David C. (Naperville, IL); Robinson, Bryan W. (Oak Lawn, IL)

1984-01-01T23:59:59.000Z

74

Heat exchanger with auxiliary cooling system  

DOE Patents [OSTI]

A heat exchanger with an auxiliary cooling system capable of cooling a nuclear reactor should the normal cooling mechanism become inoperable. A cooling coil is disposed around vertical heat transfer tubes that carry secondary coolant therethrough and is located in a downward flow of primary coolant that passes in heat transfer relationship with both the cooling coil and the vertical heat transfer tubes. A third coolant is pumped through the cooling coil which absorbs heat from the primary coolant which increases the downward flow of the primary coolant thereby increasing the natural circulation of the primary coolant through the nuclear reactor.

Coleman, John H. (Salem Township, Westmoreland County, PA)

1980-01-01T23:59:59.000Z

75

The CANDU Reactor System: An Appropriate Technology  

Science Journals Connector (OSTI)

The CANDU Reactor System: An Appropriate Technology...Chalk River, Ontario, Canada K0J 1J0 CANDU power reactors are characterized by the combination...breeder. These and other features make the CANDU system an appropriate technology for countries...

J. A. L. Robertson

1978-02-10T23:59:59.000Z

76

Method of and apparatus for removing silicon from a high temperature sodium coolant  

DOE Patents [OSTI]

A method of and system for removing silicon from a high temperature liquid sodium coolant system for a nuclear reactor. The sodium is cooled to a temperature below the silicon saturation temperature and retained at such reduced temperature while inducing high turbulence into the sodium flow for promoting precipitation of silicon compounds and ultimate separation of silicon compound particles from the liquid sodium.

Yunker, Wayne H. (Richland, WA); Christiansen, David W. (Kennewick, WA)

1987-01-01T23:59:59.000Z

77

A comprehensive approach to selecting the water chemistry of the secondary coolant circuit in the projects of nuclear power stations equipped with VVER-1200 reactors  

Science Journals Connector (OSTI)

The paper presents the results obtained from studies on selecting the water chemistry of the secondary coolant circuit carried out for the project of a nuclear power station equipped with a new-generation VVER-12...

V. F. Tyapkov

2011-05-01T23:59:59.000Z

78

SciTech Connect: Nuclear power reactor instrumentation systems...  

Office of Scientific and Technical Information (OSTI)

Nuclear power reactor instrumentation systems handbook. Volume 1 Citation Details In-Document Search Title: Nuclear power reactor instrumentation systems handbook. Volume 1 You...

79

CFD Model Development and validation for High Temperature Gas Cooled Reactor Cavity Cooling System (RCCS) Applications  

SciTech Connect (OSTI)

The Reactor Cavity Cooling Systems (RCCS) is a passive safety system that will be incorporated in the VTHR design. The system was designed to remove the heat from the reactor cavity and maintain the temperature of structures and concrete walls under desired limits during normal operation (steady-state) and accident scenarios. A small scale (1:23) water-cooled experimental facility was scaled, designed, and constructed in order to study the complex thermohydraulic phenomena taking place in the RCCS during stead-state and transient conditions. The facility represents a portion of the reactor vessel with nine stainless steel coolant risers and utilizes water as coolant. The facility was equipped with instrumentation to measure temperatures and flow rates and a general verification was completed during the shakedown. A model of the experimental facility was prepared using RELAP5-3D and simulations were performed to validate the scaling procedure. The experimental data produced during the stead-state run were compared with the simulation results obtained using RELAP5-3D. The overall behavior of the facility met the expectations. The facility capabilities were confirmed to be very promising in performing additional experimental tests, including flow visualization, and produce data for code validation.

Hassan, Yassin; Corradini, Michael; Tokuhiro, Akira; Wei, Thomas Y.C.

2014-07-14T23:59:59.000Z

80

Radiation safety assessment of a system of small reactors for distributed energy  

Science Journals Connector (OSTI)

......condition that the reactor was operated at full...Coolant water 55.0 Reactor vessel 30.0 Containment...at utilisation of nuclear energy other than electricity generation(3). Two PSRD units of 100 MW thermal reactor power are located......

N. Odano; T. Ishida

2005-12-20T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Control system for a small fission reactor  

DOE Patents [OSTI]

A system for controlling the reactivity of a small fission reactor includes an elongated, flexible hollow tube in the general form of a helical coiled spring axially positioned around and outside of the reactor vessel in an annular space between the reactor vessel and a surrounding cylindrical-shaped neutron reflector. A neutron absorbing material is provided within the hollow tube with the rate of the reaction controlled by the extension and compression of the hollow tube, e.g., extension of the tube increases reactivity while its compression reduces reactivity, in varying the amount of neutron absorbing material disposed between the reactor vessel and the neutron reflector. Conventional mechanical displacement means may be employed to control the coil density of the hollow tube as desired.

Burelbach, J.P.; Kann, W.J.; Saiveau, J.G.

1985-02-08T23:59:59.000Z

82

Corrosion and testing of engine coolants  

SciTech Connect (OSTI)

Corrosion protection is essential to any engine coolant. The wide range of metals and materials utilized in automobile engine cooling systems requires a complex of additives for corrosion resistance. A basic understanding of corrosion mechanisms and influences of individual metals is fundamental to successful formulation. Several types of corrosion can occur and these are addressed by different ASTM engine coolant testing methods. The desire for longer-life coolants emphasizes the need for newer testing methods to successfully simulate engine coolant requirements. Extension of current methods and new approaches to providing protection is discussed.

Beal, R.E. [Amalgamated Technologies, Inc., Scottsdale, AZ (United States)

1999-08-01T23:59:59.000Z

83

Cascade and secondary coolant supermarket refrigeration systems : modelling and new frost correlations.  

E-Print Network [OSTI]

??Nowadays traditional (direct expansion) supermarket refrigeration systems are mostly employed in supermarket establishments for refrigerating food products and beverages in the store. However, the installations… (more)

Haile-Michael, Getu

2011-01-01T23:59:59.000Z

84

Dynamic Impregnator Reactor System (Poster)  

SciTech Connect (OSTI)

IBRF poster developed for the IBRF showcase. Describes the multifarious system designed for complex feedstock impregnation and processing. IBRF feedstock system has several unit operations combined into one robust system that provides for flexible and staged process configurations, such as spraying, soaking, low-severity pretreatment, enzymatic hydrolysis, fermentation, concentration/evaporation, and distillation.

Not Available

2012-09-01T23:59:59.000Z

85

Bypass valve and coolant flow controls for optimum temperatures in waste heat recovery systems  

DOE Patents [OSTI]

Implementing an optimized waste heat recovery system includes calculating a temperature and a rate of change in temperature of a heat exchanger of a waste heat recovery system, and predicting a temperature and a rate of change in temperature of a material flowing through a channel of the waste heat recovery system. Upon determining the rate of change in the temperature of the material is predicted to be higher than the rate of change in the temperature of the heat exchanger, the optimized waste heat recovery system calculates a valve position and timing for the channel that is configurable for achieving a rate of material flow that is determined to produce and maintain a defined threshold temperature of the heat exchanger, and actuates the valve according to the calculated valve position and calculated timing.

Meisner, Gregory P

2013-10-08T23:59:59.000Z

86

Heat pipe based passive emergency core cooling system for safe shutdown of nuclear power reactor  

Science Journals Connector (OSTI)

Abstract On March 11th, 2011, a natural disaster created by earthquakes and Tsunami caused a serious potential of nuclear reactor meltdown in Fukushima due to the failure of Emergency Core Cooling System (ECCS) powered by diesel generators. In this paper, heat pipe based ECCS has been proposed for nuclear power plants. The designed loop type heat pipe ECCS is composed of cylindrical evaporator with 62 vertical tubes, each 150 mm diameter and 6 m length, mounted around the circumference of nuclear fuel assembly and 21 m × 10 m × 5 m naturally cooled finned condenser installed outside the primary containment. Heat pipe with overall thermal resistance of 1.44 × 10?5 °C/W will be able to reduce reactor temperature from initial working temperature of 282 °C to below 250 °C within 7 h. The overall ECCS also includes feed water flooding of the core using elevated water tank for initial 10 min which will accelerate cooling of the core, replenish core coolant during loss of coolant accident and avoids heat transfer crisis phenomena during heat pipe start-up process. The proposed heat pipe system will operate in fully passive mode with high runtime reliability and therefore provide safer environment to nuclear power plants.

Masataka Mochizuki; Randeep Singh; Thang Nguyen; Tien Nguyen

2014-01-01T23:59:59.000Z

87

Experimental Studies of NGNP Reactor Cavity Cooling System With Water  

SciTech Connect (OSTI)

This project will investigate the flow behavior that can occur in the reactor cavity cooling system (RCCS) with water coolant under the passive cooling-mode of operation. The team will conduct separate-effects tests and develop associated scaling analyses, and provide system-level phenomenological and computational models that describe key flow phenomena during RCCS operation, from forced to natural circulation, single-phase flow and two-phase flow and flashing. The project consists of the following tasks: Task 1. Conduct separate-effects, single-phase flow experiments and develop scaling analyses for comparison to system-level computational modeling for the RCCS standpipe design. A transition from forced to natural convection cooling occurs in the standpipe under accident conditions. These tests will measure global flow behavior and local flow velocities, as well as develop instrumentation for use in larger scale tests, thereby providing proper flow distribution among standpipes for decay heat removal. Task 2. Conduct separate-effects experiments for the RCCS standpipe design as two-phase flashing occurs and flow develops. As natural circulation cooling continues without an ultimate heat sink, water within the system will heat to temperatures approaching saturation , at which point two-phase flashing and flow will begin. The focus is to develop a phenomenological model from these tests that will describe the flashing and flow stability phenomena. In addition, one could determine the efficiency of phase separation in the RCCS storage tank as the two-phase flashing phenomena ensues and the storage tank vents the steam produced. Task 3. Develop a system-level computational model that will describe the overall RCCS behavior as it transitions from forced flow to natural circulation and eventual two-phase flow in the passive cooling-mode of operation. This modeling can then be used to test the phenomenological models developed as a function of scale.

Michael Corradini; Mark Anderson; Yassin Hassan; Akira Tokuhiro

2013-01-16T23:59:59.000Z

88

Vertical Pretreatment Reactor System (Poster)  

SciTech Connect (OSTI)

IBRF poster developed for the IBRF showcase. Describes the two-vessel system for primary and secondary pretreatment of biomass solids at different temperatures.

Not Available

2012-09-01T23:59:59.000Z

89

Automated Test Coverage Measurement for Reactor Protection System Software  

E-Print Network [OSTI]

Automated Test Coverage Measurement for Reactor Protection System Software Implemented in Function- ing a case study using test cases prepared by domain experts for reactor protection system software) are widely used to implement safety- critical systems such as nuclear reactor protection systems, testing

90

Direct conversion nuclear reactor space power systems  

SciTech Connect (OSTI)

This paper presents the results of a study of space nuclear reactor power systems using either thermoelectric or thermionic energy converters. An in-core reactor design and two heat pipe cooled out-of-core reactor designs were considered. One of the out-of-core cases utilized, long heat pipes (LHP) directly coupled to the energy converter. The second utilized a larger number of smaller heat pipes (mini-pipe) radiatively coupled to the energy converter. In all cases the entire system, including power conditioning, was constrained to be launched in a single shuttle flight. Assuming presently available performance, both the LHP thermoelectric system and minipipe thermionic system, designed to produce 100 kWe for seven years, would have a specific mass near 22kg/kWe. The specific mass of the thermionic minipipe system designed for a one year mission is 165 kg/kWe due to less fuel swelling. Shuttle imposed growth limits are near 300 kWe and 1.2 MWe for the thermoelectric and thermionic systems, respectively. Converter performance improvements could double this potential, and over 10 MWe may be possible for very short missions.

Britt, E.J.; Fitzpatrick, G.O.

1982-08-01T23:59:59.000Z

91

Microchannel Reactor System for Catalytic Hydrogenation  

SciTech Connect (OSTI)

We successfully demonstrated a novel process intensification concept enabled by the development of microchannel reactors, for energy efficient catalytic hydrogenation reactions at moderate temperature, and pressure, and low solvent levels. We designed, fabricated, evaluated, and optimized a laboratory-scale microchannel reactor system for hydrogenation of onitroanisole and a proprietary BMS molecule. In the second phase of the program, as a prelude to full-scale commercialization, we designed and developed a fully-automated skid-mounted multichannel microreactor pilot plant system for multiphase reactions. The system is capable of processing 1 – 10 kg/h of liquid substrate, and an industrially relevant immiscible liquid-liquid was successfully demonstrated on the system. Our microreactor-based pilot plant is one-of-akind. We anticipate that this process intensification concept, if successfully demonstrated, will provide a paradigm-changing basis for replacing existing energy inefficient, cost ineffective, environmentally detrimental slurry semi-batch reactor-based manufacturing practiced in the pharmaceutical and fine chemicals industries.

Adeniyi Lawal; Woo Lee; Ron Besser; Donald Kientzler; Luke Achenie

2010-12-22T23:59:59.000Z

92

Staged membrane oxidation reactor system  

DOE Patents [OSTI]

Ion transport membrane oxidation system comprising (a) two or more membrane oxidation stages, each stage comprising a reactant zone, an oxidant zone, one or more ion transport membranes separating the reactant zone from the oxidant zone, a reactant gas inlet region, a reactant gas outlet region, an oxidant gas inlet region, and an oxidant gas outlet region; (b) an interstage reactant gas flow path disposed between each pair of membrane oxidation stages and adapted to place the reactant gas outlet region of a first stage of the pair in flow communication with the reactant gas inlet region of a second stage of the pair; and (c) one or more reactant interstage feed gas lines, each line being in flow communication with any interstage reactant gas flow path or with the reactant zone of any membrane oxidation stage receiving interstage reactant gas.

Repasky, John Michael; Carolan, Michael Francis; Stein, VanEric Edward; Chen, Christopher Ming-Poh

2012-09-11T23:59:59.000Z

93

Staged membrane oxidation reactor system  

DOE Patents [OSTI]

Ion transport membrane oxidation system comprising (a) two or more membrane oxidation stages, each stage comprising a reactant zone, an oxidant zone, one or more ion transport membranes separating the reactant zone from the oxidant zone, a reactant gas inlet region, a reactant gas outlet region, an oxidant gas inlet region, and an oxidant gas outlet region; (b) an interstage reactant gas flow path disposed between each pair of membrane oxidation stages and adapted to place the reactant gas outlet region of a first stage of the pair in flow communication with the reactant gas inlet region of a second stage of the pair; and (c) one or more reactant interstage feed gas lines, each line being in flow communication with any interstage reactant gas flow path or with the reactant zone of any membrane oxidation stage receiving interstage reactant gas.

Repasky, John Michael; Carolan, Michael Francis; Stein, VanEric Edward; Chen, Christopher Ming-Poh

2014-05-20T23:59:59.000Z

94

Staged membrane oxidation reactor system  

DOE Patents [OSTI]

Ion transport membrane oxidation system comprising (a) two or more membrane oxidation stages, each stage comprising a reactant zone, an oxidant zone, one or more ion transport membranes separating the reactant zone from the oxidant zone, a reactant gas inlet region, a reactant gas outlet region, an oxidant gas inlet region, and an oxidant gas outlet region; (b) an interstage reactant gas flow path disposed between each pair of membrane oxidation stages and adapted to place the reactant gas outlet region of a first stage of the pair in flow communication with the reactant gas inlet region of a second stage of the pair; and (c) one or more reactant interstage feed gas lines, each line being in flow communication with any interstage reactant gas flow path or with the reactant zone of any membrane oxidation stage receiving interstage reactant gas.

Repasky, John Michael; Carolan, Michael Francis; Stein, VanEric Edward; Chen, Christopher Ming-Poh

2013-04-16T23:59:59.000Z

95

Advanced Nuclear Reactor Systems – An Indian Perspective  

Science Journals Connector (OSTI)

The Indian nuclear power programme envisages use of closed nuclear fuel cycle and thorium utilisation as its mainstay for its sustainable growth. The current levels of deployment of nuclear energy in India need to be multiplied nearly hundred fold to reach levels of electricity generation that would facilitate the country to achieve energy independence as well as a developed status. The Indian thorium based nuclear energy systems are being developed to achieve sustainability in respect of fuel resource along with enhanced safety and reduced waste generation. Advanced Heavy Water Reactor and its variants have been designed to meet these objectives. The Indian High Temperature Reactor programme also envisages use of thorium-based fuel with advanced levels of passive safety features.

Ratan Kumar Sinha

2011-01-01T23:59:59.000Z

96

Dynalene Fuel Cell Coolants Achieve Commercial Success  

Office of Energy Efficiency and Renewable Energy (EERE)

Dynalene has been working with several automotive and fuel cell manufacturers on using the coolants in their PEM fuel cells, hybrid electric, electric vehicles and back-up power systems.

97

Systems analysis of the CANDU 3 Reactor  

SciTech Connect (OSTI)

This report presents the results of a systems failure analysis study of the CANDU 3 reactor design; the study was performed for the US Nuclear Regulatory Commission. As part of the study a review of the CANDU 3 design documentation was performed, a plant assessment methodology was developed, representative plant initiating events were identified for detailed analysis, and a plant assessment was performed. The results of the plant assessment included classification of the CANDU 3 event sequences that were analyzed, determination of CANDU 3 systems that are ``significant to safety,`` and identification of key operator actions for the analyzed events.

Wolfgong, J.R.; Linn, M.A.; Wright, A.L.; Olszewski, M.; Fontana, M.H. [Oak Ridge National Lab., TN (United States)

1993-07-01T23:59:59.000Z

98

Coolant Sub-Channel and Smeared-Cracking Models in BISON | Department of  

Broader source: Energy.gov (indexed) [DOE]

Coolant Sub-Channel and Smeared-Cracking Models in BISON Coolant Sub-Channel and Smeared-Cracking Models in BISON Coolant Sub-Channel and Smeared-Cracking Models in BISON January 29, 2013 - 10:45am Addthis Coolant Sub-Channel and Smeared-Cracking Models in BISON A single-pin coolant sub-channel model was implemented in BISON, the pin-scale simulation code. This enables BISON to compute the heat transfer coefficient and coolant temperature as a function of axial position along the fuel pin (rather than requiring this information to be supplied by the user). At present, the model is only applicable to pressurized water reactor coolant conditions, but modifications to include boiling water reactor (BWR) coolant conditions are in progress. A preliminary UO2 thermal and irradiation creep model has been implemented in BISON and is

99

Nuclear reactor with internal thimble-type delayed neutron detection system  

DOE Patents [OSTI]

This invention teaches improved apparatus for the method of detecting a breach in cladded fuel used in a nuclear reactor. The detector apparatus is located in the primary heat exchanger which conveys part of the reactor coolant past at least three separate delayed-neutron detectors mounted in this heat exchanger. The detectors are spaced apart such that the coolant flow time from the core to each detector is different, and these differences are known. The delayed-neutron activity at the detectors is a function of the delay time after the reaction in the fuel until the coolant carrying the delayed-neutron emitter passes the respective detector. This time delay is broken down into separate components including an isotopic holdup time required for the emitter to move through the fuel from the reaction to the coolant at the breach, and two transit times required for the emitter now in the coolant to flow from the breach to the detector loop and then via the loop to the detector. At least two of these time components are determined during calibrated operation of the reactor. Thereafter during normal reactor operation, repeated comparisons are made by the method of regression approximation of the third time component for the best-fit line correlating measured delayed-neutron activity against activity that is approximated according to specific equations. The equations use these time-delay components and known parameter values of the fuel and of the part and emitting daughter isotopes.

Gross, Kenny C. (Lemont, IL); Poloncsik, John (Downers Grove, IL); Lambert, John D. B. (Wheaton, IL)

1990-01-01T23:59:59.000Z

100

Development of a system model for advanced small modular reactors.  

SciTech Connect (OSTI)

This report describes a system model that can be used to analyze three advance small modular reactor (SMR) designs through their lifetime. Neutronics of these reactor designs were evaluated using Monte Carlo N-Particle eXtended (MCNPX/6). The system models were developed in Matlab and Simulink. A major thrust of this research was the initial scoping analysis of Sandia's concept of a long-life fast reactor (LLFR). The inherent characteristic of this conceptual design is to minimize the change in reactivity over the lifetime of the reactor. This allows the reactor to operate substantially longer at full power than traditional light water reactors (LWRs) or other SMR designs (e.g. high temperature gas reactor (HTGR)). The system model has subroutines for lifetime reactor feedback and operation calculations, thermal hydraulic effects, load demand changes and a simplified SCO2 Brayton cycle for power conversion.

Lewis, Tom Goslee,; Holschuh, Thomas Vernon,

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Advanced thermionic reactor systems design code  

SciTech Connect (OSTI)

An overall systems design code is under development to model an advanced in-core thermionic nuclear reactor system for space applications at power levels of 10 to 50 kWe. The design code is written in an object-oriented programming environment that allows the use of a series of design modules, each of which is responsible for the determination of specific system parameters. The code modules include a neutronics and core criticality module, a core thermal hydraulics module, a thermionic fuel element performance module, a radiation shielding module, a module for waste heat transfer and rejection, and modules for power conditioning and control. The neutronics and core criticality module determines critical core size, core lifetime, and shutdown margins using the criticality calculation capability of the Monte Carlo Neutron and Photon Transport Code System (MCNP). The remaining modules utilize results of the MCNP analysis along with FORTRAN programming to predict the overall system performance.

Lewis, B.R.; Pawlowski, R.A.; Greek, K.J.; Klein, A.C. (Department of Nuclear Engineering, Radiation Center, C116, Oregon State University, Corvallis, Oregon 97331-5902 (US))

1991-01-01T23:59:59.000Z

102

Indirect passive cooling system for liquid metal cooled nuclear reactors  

DOE Patents [OSTI]

A liquid metal cooled nuclear reactor having a passive cooling system for removing residual heat resulting from fuel decay during reactor shutdown. The passive cooling system comprises a plurality of partitions surrounding the reactor vessel in spaced apart relation forming intermediate areas for circulating heat transferring fluid which remove and carry away heat from the reactor vessel. The passive cooling system includes a closed primary fluid circuit through the partitions surrounding the reactor vessel and a partially adjoining secondary open fluid circuit for carrying transferred heat out into the atmosphere.

Hunsbedt, Anstein (Los Gatos, CA); Boardman, Charles E. (Saratoga, CA)

1990-01-01T23:59:59.000Z

103

Weld monitor and failure detector for nuclear reactor system  

DOE Patents [OSTI]

Critical but inaccessible welds in a nuclear reactor system are monitored throughout the life of the reactor by providing small aperture means projecting completely through the reactor vessel wall and also through the weld or welds to be monitored. The aperture means is normally sealed from the atmosphere within the reactor. Any incipient failure or cracking of the weld will cause the environment contained within the reactor to pass into the aperture means and thence to the outer surface of the reactor vessel where its presence is readily detected.

Sutton, Jr., Harry G. (Mt. Lebanon, PA)

1987-01-01T23:59:59.000Z

104

Engine coolant testing: Second symposium  

SciTech Connect (OSTI)

This book presents the papers given at a symposium on the performance testing of engine coolants. Topics considered at the symposium included test methods for the development of supplemental additives for heavy-duty diesel engine coolants, a review of factors influencing coolant-metal interfaces in engines, corrosivity, and the evaluation of engine coolants by electrochemical methods.

Beal, R.E.

1984-01-01T23:59:59.000Z

105

Engine coolant testing: Fourth volume  

SciTech Connect (OSTI)

The 25 papers in this proceeding are arranged under the following topical sections: Organic acid inhibitor technology; Test methods; Heavy-duty coolant technology; Engine coolant recycling technology; Engine coolant characteristics and quality; and Engine coolant service and disposal. Papers within scope have been processed separately for inclusion on the data base.

Beal, R.E. [ed.

1999-08-01T23:59:59.000Z

106

Hybrid Molten Salt Reactor (HMSR): Method and System to fully...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Hybrid Molten Salt Reactor (HMSR): Method and System to fully fission actinides for electric power production without fuel enrichment, fabrication, or reprocessing A method for...

107

Heavy-duty fleet test evaluation of recycled engine coolant  

SciTech Connect (OSTI)

A 240,000 mile (386,232 km) fleet test was conducted to evaluate recycled engine coolant against factory fill coolant. The fleet consisted of 12 new Navistar International Model 9600 trucks equipped with Detroit Diesel Series 60 engines. Six of the trucks were drained and filled with the recycled engine coolant that had been recycled by a chemical treatment/filtration/reinhibited process. The other six test trucks contained the factory filled coolant. All the trucks followed the same maintenance practices which included the use of supplemental coolant additives. The trucks were equipped with metal specimen bundles. Metal specimen bundles and coolant samples were periodically removed to monitor the cooling system chemistry. A comparison of the solution chemistry and metal coupon corrosion patterns for the recycled and factory filled coolants is presented and discussed.

Woyciesjes, P.M.; Frost, R.A. [Prestone Products Corp., Danbury, CT (United States). Coolant Group

1999-08-01T23:59:59.000Z

108

Analysis of a 4-inch small-break loss-of-coolant accident in a Westinghouse Pressurized Water Reactor using TRAC-PF1/MOD1  

E-Print Network [OSTI]

the transient response of a Westinghouse 4- loop PWR using 17x17 fuel assemblies in a 14-ft. long reactor core to a 4-inch diameter SBLOCA with the computer code TRAC-PF1/MOD1, This is unique in that there are only two Westinghouse PWRs with 14-ft. cores (The... 4-inch SBLOCAs 65 XI. Comparison of RESAR-3S, TRAC and RELAP SBLOCAs . . 70 LIST OF ACRONYMS Acronym Name CCFL CVCS ECCS EPRI FSAR HPI INEL LB LOCA LOCA LPI MSIV NRC PCT PORV PWR RCP RCS RESAR RHR SI SBLOCA Argonne National...

Knippel, Kimberley I.R.

2012-06-07T23:59:59.000Z

109

Fast reactor power plant design having heat pipe heat exchanger  

DOE Patents [OSTI]

The invention relates to a pool-type fission reactor power plant design having a reactor vessel containing a primary coolant (such as liquid sodium), and a steam expansion device powered by a pressurized water/steam coolant system. Heat pipe means are disposed between the primary and water coolants to complete the heat transfer therebetween. The heat pipes are vertically oriented, penetrating the reactor deck and being directly submerged in the primary coolant. A U-tube or line passes through each heat pipe, extended over most of the length of the heat pipe and having its walls spaced from but closely proximate to and generally facing the surrounding walls of the heat pipe. The water/steam coolant loop includes each U-tube and the steam expansion device. A heat transfer medium (such as mercury) fills each of the heat pipes. The thermal energy from the primary coolant is transferred to the water coolant by isothermal evaporation-condensation of the heat transfer medium between the heat pipe and U-tube walls, the heat transfer medium moving within the heat pipe primarily transversely between these walls.

Huebotter, P.R.; McLennan, G.A.

1984-08-30T23:59:59.000Z

110

Fast reactor power plant design having heat pipe heat exchanger  

DOE Patents [OSTI]

The invention relates to a pool-type fission reactor power plant design having a reactor vessel containing a primary coolant (such as liquid sodium), and a steam expansion device powered by a pressurized water/steam coolant system. Heat pipe means are disposed between the primary and water coolants to complete the heat transfer therebetween. The heat pipes are vertically oriented, penetrating the reactor deck and being directly submerged in the primary coolant. A U-tube or line passes through each heat pipe, extended over most of the length of the heat pipe and having its walls spaced from but closely proximate to and generally facing the surrounding walls of the heat pipe. The water/steam coolant loop includes each U-tube and the steam expansion device. A heat transfer medium (such as mercury) fills each of the heat pipes. The thermal energy from the primary coolant is transferred to the water coolant by isothermal evaporation-condensation of the heat transfer medium between the heat pipe and U-tube walls, the heat transfer medium moving within the heat pipe primarily transversely between these walls.

Huebotter, Paul R. (Western Springs, IL); McLennan, George A. (Downers Grove, IL)

1985-01-01T23:59:59.000Z

111

Nuclear reactor fuel rod attachment system  

DOE Patents [OSTI]

A reusable system for removably attaching a nuclear reactor fuel rod (12) to a support member (14). A locking cap (22) is secured to the fuel rod (12) and a locking strip (24) is fastened to the support member (14). The locking cap (22) has two opposing fingers (24a and 24b) shaped to form a socket having a body portion (26). The locking strip has an extension (36) shaped to rigidly attach to the socket's body portion (26). The locking cap's fingers are resiliently deflectable. For attachment, the locking cap (22) is longitudinally pushed onto the locking strip (24) causing the extension (36) to temporarily deflect open the fingers (24a and 24b) to engage the socket's body portion (26). For removal, the process is reversed.

Christiansen, David W. (Kennewick, WA)

1982-01-01T23:59:59.000Z

112

Fluid sampling system for a nuclear reactor  

DOE Patents [OSTI]

A system of extracting fluid samples, either liquid or gas, from the interior of a nuclear reactor containment utilizes a jet pump. To extract the sample fluid, a nonradioactive motive fluid is forced through the inlet and discharge ports of a jet pump located outside the containment, creating a suction that draws the sample fluid from the containment through a sample conduit connected to the pump suction port. The mixture of motive fluid and sample fluid is discharged through a return conduit to the interior of the containment. The jet pump and means for removing a portion of the sample fluid from the sample conduit can be located in a shielded sample grab station located next to the containment. A non-nuclear grade active pump can be located outside the grab sampling station and the containment to pump the nonradioactive motive fluid through the jet pump.

Lau, Louis K. (Monroeville, PA); Alper, Naum I. (Monroeville, PA)

1994-01-01T23:59:59.000Z

113

Reactor noise analysis applications in NPP I and C systems  

SciTech Connect (OSTI)

Reactor noise analysis techniques are used in many NPPs on a routine basis as 'inspection tools' to get information on the dynamics of reactor processes and their instrumentation in a passive, non-intrusive way. The paper discusses some of the tasks and requirements an NPP has to take to implement and to use the full advantages of reactor noise analysis techniques. Typical signal noise analysis applications developed for the monitoring of the reactor shutdown system and control system instrumentation of the Candu units of Ontario Power Generation and Bruce Power are also presented. (authors)

Gloeckler, O. [International Atomic Energy Agency, Wagramer Strosse 5, A-1400 Vienna, Austria Ontario Power Generation, 230 Westney Road South, Ajax, Ont. L1S 7R3 (Canada)

2006-07-01T23:59:59.000Z

114

Tanden Mirror Reactor Systems Code (TMRSC)  

SciTech Connect (OSTI)

This paper describes a computer code developed to model a tandem mirror reactor. This is the first tandem mirror reactor model to couple the highly linked physics, magnetics, and neutronic analysis into a single code. Results from this code for two sensitivity studies are included in this paper. These studies are designed (1) to determine the impact of center cell plasma radius, length, and ion temperature on reactor cost and performance at constant fusion power and (2) to determine the impact of reactor power level on cost.

Reid, R.L.; Rothe, K.E.; Barrett, R.J.

1985-01-01T23:59:59.000Z

115

System reliability: An example of nuclear reactor system analysis  

Science Journals Connector (OSTI)

This paper presents an overview of the three reliability investigations of a 900 \\{MWe\\} reactor residual heat removal system. Following a description of the system and its functions, the main procedures used in operational reliability analysis, based on the analysis of occurence records, are covered. The second part of the investigations covers predicted reliability, involving the use of the Markov method. It will be noted that the two types of analysis are in good agreement, the probability of system loss after two months' operation being of the order of 10?1. Additional investigation data are also given.

R. Coudray; J.M. Mattei

1984-01-01T23:59:59.000Z

116

Thermal analysis for fuel handling system for sodium cooled reactor considering minor actinide-bearing metal fuel.  

SciTech Connect (OSTI)

The Advanced Burner Reactor (ABR) is one of the components of the Global Nuclear Energy Partnership (GNEP) used to close the fuel cycle. ABR is a sodium-cooled fast reactor that is used to consume transuranic elements resulting from the reprocessing of light water reactor spent nuclear fuel. ABR-1000 [1000 MW(thermal)] is a fast reactor concept created at Argonne National Laboratory to be used as a reference concept for various future trade-offs. ABR-1000 meets the GNEP goals although it uses what is considered base sodium fast reactor technology for its systems and components. One of the considerations of any fast reactor plant concept is the ability to perform fuel-handling operations with new and spent fast reactor fuel. The transmutation fuel proposed as the ABR fuel has a very little experience base, and thus, this paper investigates a fuel-handling concept and potential issues of handling fast reactor fuel containing minor actinides. In this study, two thermal analyses supporting a conceptual design study on the ABR-1000 fuel-handling system were carried out. One analysis investigated passive dry spent fuel storage, and the other analysis investigated a fresh fuel shipping cask. Passive dry storage can be made suitable for the ABR-1000 spent fuel storage with sodium-bonded metal fuel. The thermal analysis shows that spent fast reactor fuel with a decay heat of 2 kW or less can be stored passively in a helium atmosphere. The 2-kW value seems to be a reasonable and practical level, and a combination of reasonably-sized in-sodium storage followed by passive dry storage could be a candidate for spent fuel storage for the next-generation sodium-cooled reactor with sodium-bonded metal fuel. Requirements for the shipping casks for minor actinide-bearing fuel with a high decay heat level are also discussed in this paper. The shipping cask for fresh sodium-cooled-reactor fuel should be a dry type to reduce the reaction between residual moisture on fresh fuel and the sodium coolant. The cladding temperature requirement is maintained below the creep temperature limit to avoid any damage before core installation. The thermal analysis shows that a helium gas-filled cask can accommodate ABR-1000 fresh minor actinide-bearing fuel with 700-W decay heat. The above analysis results revealed the overall requirement for minor actinide-bearing metal fuel handling. The information is thought to be helpful in the design of the ABR-1000 and future sodium-cooled-reactor fuel-handling system.

Chikazawa, Y.; Grandy, C.; Nuclear Engineering Division

2009-03-01T23:59:59.000Z

117

Scaling Analysis for the Direct Reactor Auxillary Cooling System For AHTRS  

SciTech Connect (OSTI)

The Direct Reactor Auxiliary Cooling System (DRACS) is a passive heat removal system proposed for the Advanced High-Temperature Reactor (AHTR) that combines the coated particle fuel and graphite moderator with a liquid fluoride salt as the coolant. The DRACS features three coupled natural circulation/convection loops relying completely on buoyancy as the driving force. In the DRACS, two heat exchangers, namely, the DRACS Heat Exchanger (DHX) and the Natural Draft Heat Exchanger (NDHX) are used to couple these loops. In addition, a fluidic diode is employed to minimize the parasitic flow during normal operation of the reactor and to activate the DRACS in accidents. While the DRACS concept has been proposed, there are no actual prototypic DRACS systems for AHTRs built and tested in the literature. In this paper, a detailed scaling analysis for the DRACS is performed, which will provide guidance for the design of the scaled-down DRACS test facilities. Based on the Boussinesq assumption and one-dimensional flow formulation, the governing equations are non-dimensionalized by introducing appropriate dimensionless parameters. The key dimensionless numbers that characterize the DRACS system are obtained straightforwardly from the non-dimensional governing equations. Based on the dimensionless numbers and non-dimensional governing equations, similarity laws are proposed. In addition, a scaling methodology has also been developed, which consists of the core scaling and loop scaling. The consistence between the core and loop scaling is examined through the reference volume ratio, which can be obtained from the core and loop scaling processes. The scaling methodology and similarity laws have been applied to obtain a design of the scaled-down high-temperature DRACS test facility (HTDF).

Lv, Q. NMN [Ohio State University] [Ohio State University; Wang, X. NMN [Ohio State University] [Ohio State University; Sun, X NMN [Ohio State University] [Ohio State University; Christensen, R. N. [Ohio State University] [Ohio State University; Blue, T. E. [Ohio State University] [Ohio State University; Yoder Jr, Graydon L [ORNL] [ORNL; Wilson, Dane F [ORNL] [ORNL; Subharwall, Piyush [Idaho National Laboratory (INL)] [Idaho National Laboratory (INL); Adams, I. [Ohio State University, Columbus] [Ohio State University, Columbus

2013-01-01T23:59:59.000Z

118

Advanced light water reactor plants System 80+{trademark} design certification program. Annual progress report, October 1, 1994--September 30, 1995  

SciTech Connect (OSTI)

The purpose of this report is to provide the status of the progress that was made towards Design Certification of System 80+{trademark} during the US government`s 1995 fiscal year. The System 80+ Advanced Light Water Reactor (ALWR) is a 3931 MW (1350 MWe) Pressurized Water Reactor (PWR). The design covers an essentially complete plant. It is based on EPRI ALWR Utility Requirements Document (URD) improvements to the Standardized System 80 Nuclear Steam Supply System (NSSS) in operation at Palo Verde Units 1, 2, and 3. The NSSS is a traditional two-loop arrangement with two steam generators, two hot legs and four cold legs, each with a reactor coolant pump. The System 80+ standard design houses the NSSS in a spherical steel containment vessel which is enclosed in a concrete shield building, thus providing the safety advantages of a dual barrier to radioactivity release. Other major features include an all-digital, human-factors-engineered control room, an alternate electrical AC power source, an In-Containment Refueling Water Storage Tank (IRWST), and plant arrangements providing complete separation of redundant trains in safety systems.

NONE

1998-09-01T23:59:59.000Z

119

Nuclear Reactor Materials and Fuels  

Science Journals Connector (OSTI)

Nuclear reactor materials and fuels can be classified into six categories: Nuclear fuel materials Nuclear clad materials Nuclear coolant materials Nuclear poison materials Nuclear moderator materials

Dr. James S. Tulenko

2012-01-01T23:59:59.000Z

120

Design Study of Pb-Bi-Cooled and NaK-Cooled Small Reactors: PBWFR and DSFR  

SciTech Connect (OSTI)

The liquid lead-bismuth eutectic (Pb-Bi) has good compatibility with water, which is different from sodium. It is expected that the Pb-Bi could be used as a coolant of the deep sea fast reactor (DSFR) and the Pb-Bi- cooled direct contact boiling water small fast reactor (PBWFR). Physics analysis of the Pb-Bi-cooled small reactor cores with and without inner control rods was performed using the computer program of General Purpose Neutronics Code System (SRAC95) developed by Japan Atomic Energy Research Institute (JAERI). The coolant of Pb-Bi seems to be good as well as NaK for small reactors. (authors)

Otsubo, Akira; Takahashi, Minoru [N1-18, Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8550 (Japan)

2004-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Metrology/viewing system for next generation fusion reactors  

SciTech Connect (OSTI)

Next generation fusion reactors require accurate measuring systems to verify sub-millimeter alignment of plasma-facing components in the reactor vessel. A metrology system capable of achieving such accuracy must be compatible with the vessel environment of high gamma radiation, high vacuum, elevated temperature, and magnetic field. This environment requires that the system must be remotely deployed. A coherent, frequency modulated laser radar system is being integrated with a remotely operated deployment system to meet these requirements. The metrology/viewing system consists of a compact laser transceiver optics module which is linked through fiber optics to the laser source and imaging units that are located outside of the harsh environment. The deployment mechanism is a telescopic-mast positioning system. This paper identifies the requirements for the International Thermonuclear Experimental Reactor metrology and viewing system, and describes a remotely operated precision ranging and surface mapping system.

Spampinato, P.T.; Barry, R.E.; Chesser, J.B.; Menon, M.M. [Oak Ridge National Lab., TN (United States); Dagher, M.A. [Boeing Rocketdyne Div., Canoga Park, CA (United States)

1997-02-01T23:59:59.000Z

122

Natural circulating passive cooling system for nuclear reactor containment structure  

DOE Patents [OSTI]

A passive cooling system for the contaminant structure of a nuclear reactor plant providing protection against overpressure within the containment attributable to inadvertent leakage or rupture of the system components. The cooling system utilizes natural convection for transferring heat imbalances and enables the discharge of irradiation free thermal energy to the atmosphere for heat disposal from the system.

Gou, Perng-Fei (Saratoga, CA); Wade, Gentry E. (Saratoga, CA)

1990-01-01T23:59:59.000Z

123

Passive cooling system for nuclear reactor containment structure  

DOE Patents [OSTI]

A passive cooling system for the contaminant structure of a nuclear reactor plant providing protection against overpressure within the containment attributable to inadvertent leakage or rupture of the system components. The cooling system utilizes natural convection for transferring heat imbalances and enables the discharge of irradiation free thermal energy to the atmosphere for heat disposal from the system.

Gou, Perng-Fei (Saratoga, CA); Wade, Gentry E. (Saratoga, CA)

1989-01-01T23:59:59.000Z

124

Vertical Pretreatment Reactor System (Poster), NREL (National Renewable Energy Laboratory)  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Vertical Pretreatment Reactor System Vertical Pretreatment Reactor System Two-vessel system for primary and secondary pretreatment at diff erent temperatures * Biomass is heated by steam injection to temperatures of 120°C to 210°C in the pressurized mixing tube * Preheated, premixed biomass is retained for specified residence time in vertical holding vessel; material continuously moves by gravity from top to bottom of reactor in plug-fl ow fashion * Residence time is adjusted by changing amount of material held in vertical vessel relative to continuous fl ow of material entering and exiting vessel * Optional additional reactor vessel allows for secondary pretreatment at lower temperatures-120°C to 180°C-with potential to add other chemical catalysts * First vessel can operate at residence

125

The CANDU Reactor System: An Appropriate Technology  

Science Journals Connector (OSTI)

...apparent. The devel-opment of Zircaloy-2 by the U.S. Bettis Laboratory in Pittsburgh, made this con-cept practicable...necessary to base a reactor de-sign on Zircaloy-2 had not Bettis work-ers been testing the material in NRX as part of a collaborative...

J. A. L. Robertson

1978-02-10T23:59:59.000Z

126

Energy Department Completes Salt Coolant Material Transfer to Czech  

Broader source: Energy.gov (indexed) [DOE]

Completes Salt Coolant Material Transfer to Czech Completes Salt Coolant Material Transfer to Czech Republic for Advanced Reactor Research Energy Department Completes Salt Coolant Material Transfer to Czech Republic for Advanced Reactor Research May 20, 2013 - 12:52pm Addthis News Media Contact (202) 586-4940 PRAGUE, CZECH REPUBLIC - The U.S. Department of Energy recently joined with the U.S. Embassy in Prague and the Czech Republic's Ministry of Industry and Trade to complete the transfer of 75 kilograms of fluoride salt from the Department's Oak Ridge National Laboratory (ORNL) to the Czech Nuclear Research Institute Řež for experiments at Řež's critical test facility. This partnership builds on a strong history of U.S.-Czech energy collaboration and follows President Obama's speech in Prague in April 2009, where he laid out the importance of international

127

System aspects of a Space Nuclear Reactor Power System  

SciTech Connect (OSTI)

Selected systems aspects of a 300 kW nuclear reactor power system for spacecraft have been studied. The approach included examination of two candidate missions and their associated spacecraft, and a number of special topics dealing with the power system design and operation. The missions considered were a reusable orbital transfer vehicle and a space-based radar. The special topics included: power system configuration and scaling, launch vehicle integration, operating altitude, orbital storage, start-up, thawing, control, load following, procedures in case of malfunction, restart, thermal and nuclear radiation to other portions of the spacecraft, thermal stresses between subsystems, boom and cable designs, vibration modes, altitude control, reliability, and survivability. Among the findings are that the stowed length of the power system is important to mission design and that orbital storage for months to years may be needed for missions involving orbital assembly. The power system design evolved during the study and has continued to evolve; the current design differs somewhat from that examined in this paper.

Jaffe, L.; Fujita, T.; Beatty, R.; Bhandari, P.; Chow, E.; Deininger, W.; Ewell, R.; Grossman, M.; Kia, T.; Nesmith, B.

1988-01-01T23:59:59.000Z

128

E-Print Network 3.0 - aerospace system test reactor Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Engineering 15 www.eprg.group.cam.ac.uk EPRGWORKINGPAPER Summary: Accelerator-Driven Subcritical Reactor Park Michel-Alexandre Cardin1 Engineering Systems Division... and reactor...

129

Dual annular rotating "windowed" nuclear reflector reactor control system  

DOE Patents [OSTI]

A nuclear reactor control system is provided in a nuclear reactor having a core operating in the fast neutron energy spectrum where criticality control is achieved by neutron leakage. The control system includes dual annular, rotatable reflector rings. There are two reflector rings: an inner reflector ring and an outer reflector ring. The reflectors are concentrically assembled, surround the reactor core, and each reflector ring includes a plurality of openings. The openings in each ring are capable of being aligned or non-aligned with each other. Independent driving means for each of the annular reflector rings is provided so that reactor criticality can be initiated and controlled by rotation of either reflector ring such that the extent of alignment of the openings in each ring controls the reflection of neutrons from the core.

Jacox, Michael G. (Idaho Falls, ID); Drexler, Robert L. (Idaho Falls, ID); Hunt, Robert N. M. (Idaho Falls, ID); Lake, James A. (Idaho Falls, ID)

1994-01-01T23:59:59.000Z

130

Development of Figure of Merits (FOMs) for Intermediate Coolant Characterization and Selection  

SciTech Connect (OSTI)

This paper focuses on characterization of several coolant performances in the IHTL. There are lots of choices available for the IHTL coolants; gases, liquid metals, molten salts, and etc. Traditionally, the selection of coolants is highly dependent on engineer's experience and decisions. In this decision, the following parameters are generally considered: melting point, vapor pressure, density, thermal conductivity, heat capacity, viscosity, and coolant chemistry. The followings are general thermal-hydraulic requirements for the coolant in the IHTL: (1) High heat transfer performance - The IHTL coolant should exhibit high heat transfer performance to achieve high efficiency and economics; (2) Low pumping power - The IHTL coolant requires low pumping power to improve economics through less stringent pump requirements; (3) Low amount of coolant volume - The IHTL coolant requires less coolant volume for better economics; (4) Low amount of structural materials - The IHTL coolant requires less structural material volume for better economics; (5) Low heat loss - The IHTL requires less heat loss for high efficiency; and (6) Low temperature drop - The IHTL should allow less temperature drop for high efficiency. Typically, heat transfer coolants are selected based on various fluid properties such as melting point, vapor pressure, density, thermal conductivity, heat capacity, viscosity, and coolant chemistry. However, the selection process & results are highly dependent on the engineer's personal experience and skills. In the coolant selection, if a certain coolant shows superior properties with respect to the others, the decision will be very straightforward. However, generally, each coolant material exhibits good characteristics for some properties but poor for the others. Therefore, it will be very useful to have some figures of merits (FOMs), which can represent and quantify various coolant thermal performances in the system of interest. The study summarized in this paper focuses on developing general FOMs for the IHTL coolant selection and shows some estimation results.

Eung Soo Kim; Piyush Sabharwall; Nolan Anderson

2011-06-01T23:59:59.000Z

131

Integrated intelligent systems in advanced reactor control rooms  

SciTech Connect (OSTI)

An intelligent, reactor control room, information system is designed to be an integral part of an advanced control room and will assist the reactor operator's decision making process by continuously monitoring the current plant state and providing recommended operator actions to improve that state. This intelligent system is an integral part of, as well as an extension to, the plant protection and control systems. This paper describes the interaction of several functional components (intelligent information data display, technical specifications monitoring, and dynamic procedures) of the overall system and the artificial intelligence laboratory environment assembled for testing the prototype. 10 refs., 5 figs.

Beckmeyer, R.R.

1989-01-01T23:59:59.000Z

132

Experimental and Computational Study of a Scaled Reactor Cavity Cooling System  

E-Print Network [OSTI]

The Very High Temperature Gas-Cooled Reactor (VHTR) is one of the next generation nuclear reactors designed to achieve high temperatures to support industrial applications and power generation. The Reactor Cavity Cooling System (RCCS) is a passive...

Vaghetto, Rodolfo

2013-11-25T23:59:59.000Z

133

Advanced Fuel Cycle Economic Analysis of Symbiotic Light-Water Reactor and Fast Burner Reactor Systems  

SciTech Connect (OSTI)

The Advanced Fuel Cycle Economic Analysis of Symbiotic Light-Water Reactor and Fast Burner Reactor Systems, prepared to support the U.S. Advanced Fuel Cycle Initiative (AFCI) systems analysis, provides a technology-oriented baseline system cost comparison between the open fuel cycle and closed fuel cycle systems. The intent is to understand their overall cost trends, cost sensitivities, and trade-offs. This analysis also improves the AFCI Program’s understanding of the cost drivers that will determine nuclear power’s cost competitiveness vis-a-vis other baseload generation systems. The common reactor-related costs consist of capital, operating, and decontamination and decommissioning costs. Fuel cycle costs include front-end (pre-irradiation) and back-end (post-iradiation) costs, as well as costs specifically associated with fuel recycling. This analysis reveals that there are large cost uncertainties associated with all the fuel cycle strategies, and that overall systems (reactor plus fuel cycle) using a closed fuel cycle are about 10% more expensive in terms of electricity generation cost than open cycle systems. The study concludes that further U.S. and joint international-based design studies are needed to reduce the cost uncertainties with respect to fast reactor, fuel separation and fabrication, and waste disposition. The results of this work can help provide insight to the cost-related factors and conditions needed to keep nuclear energy (including closed fuel cycles) economically competitive in the U.S. and worldwide. These results may be updated over time based on new cost information, revised assumptions, and feedback received from additional reviews.

D. E. Shropshire

2009-01-01T23:59:59.000Z

134

A Project Management and Systems Engineering Structure for a Generation IV Very High Temperature Reactor  

SciTech Connect (OSTI)

The Very High Temperature Reactor (VHTR) will be an advanced, very high temperature (approximately 1000o C. coolant outlet temperature), gas cooled nuclear reactor and is the nearest term of six Generation IV reactor technologies for nuclear assisted hydrogen production. In 2001, the Generation IV International Forum (GIF), a ten nation international forum working together with the Department of Energy’s (DOE) Nuclear Energy Research Advisory Committee (NERAC), agreed to proceed with the development of a technology roadmap and identified the next generation of nuclear reactor systems for producing new sources of power. Since a new reactor has not been licensed in the United States since the 1970s, the risks are too large for a single utility to assume in the development of an unprecedented Generation IV reactor. The government must sponsor and invest in the research to resolve major first of a kind (FOAK) issues through a full-scale demonstration prior to industry implementation. DOE’s primary mission for the VHTR is to demonstrate nuclear reactor assisted cogeneration of electricity and hydrogen while meeting the Generation IV goals for safety, sustainability, proliferation resistance and physical security and economics. The successful deployment of the VHTR as a demonstration project will aid in restarting the now atrophied U.S. nuclear power industry infrastructure. It is envisioned that VHTR project participants will include DOE Laboratories, industry partners such as designers, constructors, manufacturers, utilities, and Generation IV international countries. To effectively mange R&D, engineering, procurement, construction, and operation for this multi-organizational and technologically complex project, systems engineering will be used extensively to ensure delivery of the final product. Although the VHTR is an unprecedented FOAK system, the R&D, when assessed using the Office of Science and Technology Gate Model, falls primarily in the 3rd - Exploratory Development, 4th – Advanced Development, and 5th- Engineering Development stages of maturity rather than in the basic and viability stages. Therefore the R&D must be controlled and project driven from the top down to address specific issues of feasibility, proof of design or support of engineering. The design evolution must be through the systems approach including an iterative process of high-level requirements definition, engineering to focus R&D to verify feasibility, requirements development and conceptual design, R&D to verify design and refine detailed requirements for final detailed design. This paper will define a framework for project management and application of systems engineering at the Idaho National Engineering and Environmental Laboratory (INEEL). The VHTR Project includes an overall reactor design and construction activity and four major supporting activities: fuel development and qualification, materials selection and qualification, NRC licensing and regulatory support, and the hydrogen production plant.

Ed Gorski; Dennis Harrell; Finis Southworth

2004-09-01T23:59:59.000Z

135

Pressurized reactor system and a method of operating the same  

DOE Patents [OSTI]

A method and apparatus are provided for operating a pressurized reactor system in order to precisely control the temperature within a pressure vessel in order to minimize condensation of corrosive materials from gases on the surfaces of the pressure vessel or contained circulating fluidized bed reactor, and to prevent the temperature of the components from reaching a detrimentally high level, while at the same time allowing quick heating of the pressure vessel interior volume during start-up. Superatmospheric pressure gas is introduced from the first conduit into the fluidized bed reactor and heat derived reactions such as combustion and gassification are maintained in the reactor. Gas is exhausted from the reactor and pressure vessel through a second conduit. Gas is circulated from one part of the inside volume to another to control the temperature of the inside volume, such as by passing the gas through an exterior conduit which has a heat exchanger, control valve, blower and compressor associated therewith, or by causing natural convection flow of circulating gas within one or more generally vertically extending gas passages entirely within the pressure vessel (and containing heat exchangers, flow rate control valves, or the like therein). Preferably, inert gas is provided as a circulating gas, and the inert gas may also be used in emergency shut-down situations. In emergency shut-down reaction gas being supplied to the reactor is cut off, while inert gas from the interior gas volume of the pressure vessel is introduced into the reactor.

Isaksson, Juhani M. (Karhula, FI)

1996-01-01T23:59:59.000Z

136

Pressurized reactor system and a method of operating the same  

DOE Patents [OSTI]

A method and apparatus are provided for operating a pressurized reactor system in order to precisely control the temperature within a pressure vessel in order to minimize condensation of corrosive materials from gases on the surfaces of the pressure vessel or contained circulating fluidized bed reactor, and to prevent the temperature of the components from reaching a detrimentally high level, while at the same time allowing quick heating of the pressure vessel interior volume during start-up. Super-atmospheric pressure gas is introduced from the first conduit into the fluidized bed reactor and heat derived reactions such as combustion and gasification are maintained in the reactor. Gas is exhausted from the reactor and pressure vessel through a second conduit. Gas is circulated from one part of the inside volume to another to control the temperature of the inside volume, such as by passing the gas through an exterior conduit which has a heat exchanger, control valve, blower and compressor associated therewith, or by causing natural convection flow of circulating gas within one or more generally vertically extending gas passages entirely within the pressure vessel (and containing heat exchangers, flow rate control valves, or the like therein). Preferably, inert gas is provided as a circulating gas, and the inert gas may also be used in emergency shut-down situations. In emergency shut-down reaction gas being supplied to the reactor is cut off, while inert gas from the interior gas volume of the pressure vessel is introduced into the reactor. 2 figs.

Isaksson, J.M.

1996-06-18T23:59:59.000Z

137

System modeling and reactor design studies of the Advanced Thermionic Initiative space nuclear reactor  

SciTech Connect (OSTI)

In-core thermionic space reactor design concepts that operate at a nominal power output range of 20 to 50 kW(electric) are described. Details of the neutronic, thermionic, thermal hydraulics, and shielding performance are presented. Because of the strong absorption of thermal neutrons by natural tungsten and the large amount of natural tungsten within the reactor core, two designs are considered. An overall system design code has been developed at Oregon State University to model advanced in-core thermionic energy conversion-based nuclear reactor systems for space applications. The results show that the driverless single-cell Advanced Thermionic Initiative (ATI) configuration, which does not have driver fuel rods, proved to be more efficient than the driven core, which has driver rods. The results also show that the inclusion of the true axial and radial power distribution decrease the overall conversion efficiency. The flattening of the radial power distribution by three different methods would lead to a higher efficiency. The results show that only one TFE works at the optimum emitter temperature; all other TFEs are off the optimum performance and result in a 40% decrease of the efficiency of the overall system. The true axial profile is significantly different as there is a considerable amount of neutron leakage out of the top and bottom of the reactor. The analysis reveals that the axial power profile actually has a chopped cosine shape. For this axial profile, the reactor core overall efficiency for the driverless ATI reactor version is found to be 5.84% with a total electrical power of 21.92 kW(electric). By considering the true axial power profile instead of the uniform power profile, each TFE loses {approximately}80 W(electric).

Lee, H.H.; Abdul-Hamid, S.; Klein, A.C. [Oregon State Univ., Corvallis, OR (United States). Dept. of Nuclear Engineering Radiation Center] [Oregon State Univ., Corvallis, OR (United States). Dept. of Nuclear Engineering Radiation Center

1996-07-01T23:59:59.000Z

138

Multivent effects in a large scale boiling water reactor pressure suppression system  

SciTech Connect (OSTI)

The steam-driven GKSS pressure suppression test facility, which contains 3 full scale vent pipes, has been used for 5 years to investigate the postulated loss-of-coolant accident in a Mark II and Type 69 boiling water reactor. Using the results from several of these tests, wetwell boundary load data (peak pressures and spectral power) during the chugging stage, have been evaluated for sparse pool response (one and two vents in the three vent pool) and for full pool response (one, two, or three vent operation in pools of constant wetwell pool area per vent). The sparse pool results indicate the pool-system, chug event boundary loads are strongly dependent on wetwell pool area per vent, with the load increasing with decreasing area. The full pool results show a substantial increase in the pool-system, chug event boundary loads upon a change from single cell to double cell operation; only minor change occurs in going from double to triple cell operation.

McCauley, E.W.; Aust, E.; Schwan, H.

1984-07-06T23:59:59.000Z

139

Reactor technology assessment and selection utilizing systems engineering approach  

SciTech Connect (OSTI)

The first Nuclear power plant (NPP) deployment in a country is a complex process that needs to consider technical, economic and financial aspects along with other aspects like public acceptance. Increased interest in the deployment of new NPPs, both among newcomer countries and those with expanding programs, necessitates the selection of reactor technology among commercially available technologies. This paper reviews the Systems Decision Process (SDP) of Systems Engineering and applies it in selecting the most appropriate reactor technology for the deployment in Malaysia. The integrated qualitative and quantitative analyses employed in the SDP are explored to perform reactor technology assessment and to select the most feasible technology whose design has also to comply with the IAEA standard requirements and other relevant requirements that have been established in this study. A quick Malaysian case study result suggests that the country reside with PWR (pressurized water reactor) technologies with more detailed study to be performed in the future for the selection of the most appropriate reactor technology for Malaysia. The demonstrated technology assessment also proposes an alternative method to systematically and quantitatively select the most appropriate reactor technology.

Zolkaffly, Muhammed Zulfakar; Han, Ki-In [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

2014-02-12T23:59:59.000Z

140

Hybrid Plasma Reactor/Filter for Transportable Collective Protection Systems  

SciTech Connect (OSTI)

Pacific Northwest National Laboratory (PNNL) has performed an assessment of a Hybrid Plasma/Filter system as an alternative to conventional methods for collective protection. The key premise of the hybrid system is to couple a nonthermal plasma (NTP) reactor with reactive adsorption to provide a broader envelope of protection than can be provided through a single-solution approach. The first step uses highly reactive species (e.g. oxygen radicals, hydroxyl radicals, etc.) created in a nonthermal plasma (NTP) reactor to destroy the majority (~75% - 90%) of an incoming threat. Following the NTP reactor an O3 reactor/filter uses the O3 created in the NTP reactor to further destroy the remaining organic materials. This report summarizes the laboratory development of the Hybrid Plasma Reactor/Filter to protect against a ‘worst-case’ simulant, methyl bromide (CH3Br), and presents a preliminary engineering assessment of the technology to Joint Expeditionary Collective Protection performance specifications for chemical vapor air purification technologies.

Josephson, Gary B.; Tonkyn, Russell G.; Frye, J. G.; Riley, Brian J.; Rappe, Kenneth G.

2011-04-06T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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141

Reactor protection system with automatic self-testing and diagnostic  

DOE Patents [OSTI]

A reactor protection system is disclosed having four divisions, with quad redundant sensors for each scram parameter providing input to four independent microprocessor-based electronic chassis. Each electronic chassis acquires the scram parameter data from its own sensor, digitizes the information, and then transmits the sensor reading to the other three electronic chassis via optical fibers. To increase system availability and reduce false scrams, the reactor protection system employs two levels of voting on a need for reactor scram. The electronic chassis perform software divisional data processing, vote 2/3 with spare based upon information from all four sensors, and send the divisional scram signals to the hardware logic panel, which performs a 2/4 division vote on whether or not to initiate a reactor scram. Each chassis makes a divisional scram decision based on data from all sensors. Automatic detection and discrimination against failed sensors allows the reactor protection system to automatically enter a known state when sensor failures occur. Cross communication of sensor readings allows comparison of four theoretically ``identical`` values. This permits identification of sensor errors such as drift or malfunction. A diagnostic request for service is issued for errant sensor data. Automated self test and diagnostic monitoring, sensor input through output relay logic, virtually eliminate the need for manual surveillance testing. This provides an ability for each division to cross-check all divisions and to sense failures of the hardware logic. 16 figs.

Gaubatz, D.C.

1996-12-17T23:59:59.000Z

142

Analysis of the Reactor Cavity Cooling System for Very High Temperature Gas-cooled Reactors Using Computational Fluid Dynamics Tools  

E-Print Network [OSTI]

The design of passive heat removal systems is one of the main concerns for the modular Very High Temperature Gas-Cooled Reactors (VHTR) vessel cavity. The Reactor Cavity Cooling System (RCCS) is an important heat removal system in case of accidents...

Frisani, Angelo

2011-08-08T23:59:59.000Z

143

Advanced Light Water Reactor Plants System 80+{trademark} Design Certification Program. Annual progress report, October 1, 1992--September 30, 1993  

SciTech Connect (OSTI)

The purpose of this report is to provide a status of the progress that was made towards Design Certification of System 80+{trademark} during the US government`s 1993 fiscal year. The System 80+ Advanced Light Water Reactor (ALWR) is a 3931 MW{sub t} (1350 MWe) Pressurized Water Reactor (PWR). The design consists of an essentially complete plant. It is based on evolutionary improvements to the Standardized System 80 nuclear steam supply system in operation at Palo Verde Units 1, 2, and 3, and the Duke Power Company P-81 balance-of-plant (BOP) that was designed and partially constructed at the Cherokee plant site. The System 80/P-81 original design has been substantially enhanced to increase conformance with the EPRI ALWR Utility Requirements Document (URD). Some design enhancements incorporated in the System 80+ design are included in the four units currently under construction in the Republic of Korea. These units form the basis of the Korean standardization program. The full System 80+ standard design has been offered to the Republic of China, in response to their recent bid specification. The ABB-CE Standard Safety Analysis Report (CESSAR-DC) was submitted to the NRC and a Draft Safety Evaluation Report was issued by the NRC in October 1992. CESSAR-DC contains the technical basis for compliance with the EPRI URD for simplified emergency planning. The Nuclear Steam Supply System (NSSS) is the standard ABB-Combustion Engineering two-loop arrangement with two steam generators, two hot legs and four cold legs each with a reactor coolant pump. The System 80+ standard plant includes a sperical steel containment vessel which is enclosed in a concrete shield building, thus providing the safety advantages of a dual containment.

Not Available

1993-12-31T23:59:59.000Z

144

Method for passive cooling liquid metal cooled nuclear reactors, and system thereof  

DOE Patents [OSTI]

A liquid metal cooled nuclear reactor having a passive cooling system for removing residual heat resulting from fuel decay during reactor shutdown. The passive cooling system comprises a plurality of partitions surrounding the reactor vessel in spaced apart relation forming intermediate areas for circulating heat transferring fluid which remove and carry away heat from the reactor vessel.

Hunsbedt, Anstein (Los Gatos, CA); Busboom, Herbert J. (San Jose, CA)

1991-01-01T23:59:59.000Z

145

Incipient Transient Detection in Reactor Systems: Experimental and Theoretical Investigation  

SciTech Connect (OSTI)

The main goal of this research was to develop a method for detecting reactor system transients at the earliest possible time through a comprehensive experimental, testing and benchmarking program. This approach holds strong promise for developing new diagnostic technologies that are non-intrusive, generic and highly portable across different systems. It will help in the design of new generation nuclear power reactors, which utilize passive safety systems with a reliable and non-intrusive multiphase flow diagnostic system to monitor the function of the passive safety systems. The main objective of this research was to develop an improved fuzzy logic based detection method based on a comprehensive experimental testing program to detect reactor transients at the earliest possible time, practically at their birth moment. A fuzzy logic and neural network based transient identification methodology and implemented in a computer code called PROTREN was considered in this research and was compared with SPRT (Sequentially Probability Ratio Testing) decision and Bayesian inference. The project involved experiment, theoretical modeling and a thermal-hydraulic code assessment. It involved graduate and undergraduate students participation providing them with exposure and training in advanced reactor concepts and safety systems. In this final report, main tasks performed during the project period are summarized and the selected results are presented. Detailed descriptions for the tasks and the results are presented in previous yearly reports (Revankar et al 2003 and Revankar et al 2004).

Lefteri H. Tsoukalas; S.T. Revankar; X Wang; R. Sattuluri

2005-09-27T23:59:59.000Z

146

Horizontal Pretreatment Reactor System (Poster), NREL (National Renewable Energy Laboratory)  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Diff Diff erent pretreatment chemistry/ residence time combinations are possible using these multiple horizontal-tube reactors * Each tube is indirectly and directly steam heated to temperatures of 150 0 C to 210 0 C * Residence time is varied by changing the speed of the auger that moves the biomass through each tube reactor * Tubes are used individually or in combination to achieve diff erent pretreatment residence times * Smaller tubes made from Hastelloy, an acid-resistant material, are used with more corrosive chemicals and residence times from 3 to 20 minutes * Larger tubes made from 316 stainless steel are used for residence times from 20 to 120 minutes Horizontal Pretreatment Reactor System Versatile pretreatment system for a wide range of pretreatment chemistries

147

Space-reactor electric systems: subsystem technology assessment  

SciTech Connect (OSTI)

This report documents the subsystem technology assessment. For the purpose of this report, five subsystems were defined for a space reactor electric system, and the report is organized around these subsystems: reactor; shielding; primary heat transport; power conversion and processing; and heat rejection. The purpose of the assessment was to determine the current technology status and the technology potentials for different types of the five subsystems. The cost and schedule needed to develop these potentials were estimated, and sets of development-compatible subsystems were identified.

Anderson, R.V.; Bost, D.; Determan, W.R.

1983-03-29T23:59:59.000Z

148

Design of a nuclear reactor system for lunar base applications  

E-Print Network [OSTI]

disadvantages. U02 and Pu02 fuels both have extremely poor ther mal conductivities, about 4 W/m K at 500 C, which would normally limit the maximum linear power in the reactor core to unacceptably low levels. For tunately, the ver y high melting temperatur es... conversion, however, high reactor exit temperatures are both necessary and desirable. The efficiency of the power conversion cycle is directly related to the difference between the high and low temperatur es in the system. Since the heat rejection...

Griffith, Richard Odell

2012-06-07T23:59:59.000Z

149

A gas-cooled reactor surface power system  

Science Journals Connector (OSTI)

A human outpost on Mars requires plentiful power to assure survival of the astronauts. Anywhere from 50 to 500 kW of electric power (kWe) will be needed depending on the number of astronauts level of scientific activity and life-cycle closure desired. This paper describes a 250-kWe power system based on a gas-cooled nuclear reactor with a recuperated closed Brayton cycle conversion system. The design draws upon the extensive data and engineering experience developed under the various high-temperature gas cooled reactor programs and under the SP-100 program. The reactor core is similar in power and size to the research reactors found on numerous university campuses. The fuel is uranium nitride clad in Nb1%Zr which has been extensively tested under the SP-100 program. The fuel rods are arranged in a hexagonal array within a BeO block. The BeO softens the spectrum allowing better use of the fuel and stabilizing the geometry against deformation during impact or other loadings. The system has a negative temperature feedback coefficient so that the power level will automatically follow a variable load without the need for continuous adjustment of control elements. Waste heat is removed by an air-cooled heat exchanger using cold Martian air. The amount of radioactivity in the reactor at launch is very small (less than a Curie and about equal to a truckload of uranium ore). The system will need to be engineered so that criticality can not occur for any launch accident. This system is also adaptable for electric propulsion or life-support during transit to and from Mars.

Ronald J. Lipinski; Steven A. Wright; Roger X. Lenard; Gary A. Harms

1999-01-01T23:59:59.000Z

150

Technical Letter Report, An Evaluation of Ultrasonic Phased Array Testing for Reactor Piping System Components Containing Dissimilar Metal Welds, JCN N6398, Task 2A  

SciTech Connect (OSTI)

Research is being conducted for the U.S. Nuclear Regulatory Commission at the Pacific Northwest National Laboratory to assess the effectiveness and reliability of advanced nondestructive examination (NDE) methods for the inspection of light-water reactor components. The scope of this research encom¬passes primary system pressure boundary materials including dissimilar metal welds (DMWs), cast austenitic stainless steels (CASS), piping with corrosion-resistant cladding, weld overlays, inlays and onlays, and far-side examinations of austenitic piping welds. A primary objective of this work is to evaluate various NDE methods to assess their ability to detect, localize, and size cracks in steel components that challenge standard and/or conventional inspection methodologies. This interim technical letter report provides a summary of a technical evaluation aimed at assessing the capabilities of phased-array (PA) ultrasonic testing (UT) methods as applied to the inspection of small-bore DMW components that exist in the reactor coolant systems (RCS) of pressurized water reactors (PWRs). Operating experience and events such as the circumferential cracking in the reactor vessel nozzle-to-RCS hot leg pipe at V.C. Summer nuclear power station, identified in 2000, show that in PWRs where primary coolant water (or steam) are present under normal operation, Alloy 82/182 materials are susceptible to pressurized water stress corrosion cracking. The extent and number of occurrences of DMW cracking in nuclear power plants (domestically and internationally) indicate the necessity for reliable and effective inspection techniques. The work described herein was performed to provide insights for evaluating the utility of advanced NDE approaches for the inspection of DMW components such as a pressurizer surge nozzle DMW, a shutdown cooling pipe DMW, and a ferritic (low-alloy carbon steel)-to-CASS pipe DMW configuration.

Diaz, Aaron A.; Cinson, Anthony D.; Crawford, Susan L.; Anderson, Michael T.

2009-11-30T23:59:59.000Z

151

Refueling Liquid-Salt-Cooled Very High-Temperature Reactors  

SciTech Connect (OSTI)

The liquid-salt-cooled very high-temperature reactor (LS-VHTR), also called the Advanced High-Temperature Reactor (AHTR), is a new reactor concept that combines in a novel way four established technologies: (1) coated-particle graphite-matrix nuclear fuels, (2) Brayton power cycles, (3) passive safety systems and plant designs previously developed for liquid-metal-cooled fast reactors, and (4) low-pressure liquid-salt coolants. Depending upon goals, the peak coolant operating temperatures are between 700 and 1000 deg. C, with reactor outputs between 2400 and 4000 MW(t). Several fluoride salt coolants that are being evaluated have melting points between 350 and 500 deg. C, values that imply minimum refueling temperatures between 400 and 550 deg. C. At operating conditions, the liquid salts are transparent and have physical properties similar to those of water. A series of refueling studies have been initiated to (1) confirm the viability of refueling, (2) define methods for safe rapid refueling, and (3) aid the selection of the preferred AHTR design. Three reactor cores with different fuel element designs (prismatic, pebble bed, and pin-type fuel assembly) are being evaluated. Each is a liquid-salt-cooled variant of a graphite-moderated high-temperature reactor. The refueling studies examined applicable refueling experience from high-temperature reactors (similar fuel element designs) and sodium-cooled fast reactors (similar plant design with liquid coolant, high temperatures, and low pressures). The findings indicate that refueling is viable, and several approaches have been identified. The study results are described in this paper. (authors)

Forsberg, Charles W. [Oak Ridge National Laboratory, P.O. Box 2008 Oak Ridge, TN 37831 (United States); Peterson, Per F. [Nuclear Engineering Department, University of California at Berkeley, 6124a Etcheverry Hall, Berkeley, CA 94720 (United States); Cahalan, James E. [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439 (United States); Enneking, Jeffrey A. [Areva NP (United States); Phil MacDonald [Consultant, Cedar Hill, TX (United States)

2006-07-01T23:59:59.000Z

152

Operation of staged membrane oxidation reactor systems  

SciTech Connect (OSTI)

A method of operating a multi-stage ion transport membrane oxidation system. The method comprises providing a multi-stage ion transport membrane oxidation system with at least a first membrane oxidation stage and a second membrane oxidation stage, operating the ion transport membrane oxidation system at operating conditions including a characteristic temperature of the first membrane oxidation stage and a characteristic temperature of the second membrane oxidation stage; and controlling the production capacity and/or the product quality by changing the characteristic temperature of the first membrane oxidation stage and/or changing the characteristic temperature of the second membrane oxidation stage.

Repasky, John Michael

2012-10-16T23:59:59.000Z

153

Emulsion polymerization of ethylene-vinyl acetate-branched vinyl ester using a pressure reactor system.  

E-Print Network [OSTI]

??A new pressure reactor system was designed to synthesize a novel branched ester-ethylene-vinyl acetate (BEEVA) emulsion polymer. The reactor system was capable of handling pressure… (more)

Tan, Chee Boon

2008-01-01T23:59:59.000Z

154

Advanced Nuclear Reactors | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Advanced Nuclear Advanced Nuclear Reactors Advanced Nuclear Reactors Turbulent Flow of Coolant in an Advanced Nuclear Reactor Visualizing Coolant Flow in Sodium Reactor Subassemblies Sodium-cooled Fast Reactor (SFR) Coolant Flow At the heart of a nuclear power plant is the reactor. The fuel assembly is placed inside a reactor vessel where all the nuclear reactions occur to produce the heat and steam used for power generation. Nonetheless, an entire power plant consists of many other support components and key structures like coolant pipes; pumps and tanks including their surrounding steel framing; and concrete containment and support structures. The Reactors Product Line within NEAMS is concerned with modeling the reactor vessel as well as those components of a complete power plant that

155

Summary of space nuclear reactor power systems, 1983--1992  

SciTech Connect (OSTI)

This report summarizes major developments in the last ten years which have greatly expanded the space nuclear reactor power systems technology base. In the SP-100 program, after a competition between liquid-metal, gas-cooled, thermionic, and heat pipe reactors integrated with various combinations of thermoelectric thermionic, Brayton, Rankine, and Stirling energy conversion systems, three concepts:were selected for further evaluation. In 1985, the high-temperature (1,350 K), lithium-cooled reactor with thermoelectric conversion was selected for full scale development. Since then, significant progress has been achieved including the demonstration of a 7-y-life uranium nitride fuel pin. Progress on the lithium-cooled reactor with thermoelectrics has progressed from a concept, through a generic flight system design, to the design, development, and testing of specific components. Meanwhile, the USSR in 1987--88 orbited a new generation of nuclear power systems beyond the, thermoelectric plants on the RORSAT satellites. The US has continued to advance its own thermionic fuel element development, concentrating on a multicell fuel element configuration. Experimental work has demonstrated a single cell operating time of about 1 1/2-y. Technology advances have also been made in the Stirling engine; an advanced engine that operates at 1,050 K is ready for testing. Additional concepts have been studied and experiments have been performed on a variety of systems to meet changing needs; such as powers of tens-to-hundreds of megawatts and highly survivable systems of tens-of-kilowatts power.

Buden, D.

1993-08-11T23:59:59.000Z

156

Systems and methods for dismantling a nuclear reactor  

DOE Patents [OSTI]

Systems and methods for dismantling a nuclear reactor are described. In one aspect the system includes a remotely controlled heavy manipulator ("manipulator") operatively coupled to a support structure, and a control station in a non-contaminated portion of a workspace. The support structure provides the manipulator with top down access into a bioshield of a nuclear reactor. At least one computing device in the control station provides remote control to perform operations including: (a) dismantling, using the manipulator, a graphite moderator, concrete walls, and a ceiling of the bioshield, the manipulator being provided with automated access to all internal portions of the bioshield; (b) loading, using the manipulator, contaminated graphite blocks from the graphite core and other components from the bioshield into one or more waste containers; and (c) dispersing, using the manipulator, dust suppression and contamination fixing spray to contaminated matter.

Heim, Robert R; Adams, Scott Ryan; Cole, Matthew Denver; Kirby, William E; Linnebur, Paul Damon

2014-10-28T23:59:59.000Z

157

Three-dimensional imaging and precision metrology for liquid-salt-cooled reactors  

SciTech Connect (OSTI)

The liquid-salt-cooled very high temperature reactor, also called the Advanced High-Temperature Reactor (AHTR), is a new large high-temperature reactor concept that combines in a novel way four established technologies: (1) coated-particle graphite-matrix nuclear fuels, (2) Brayton power cycles, (3) passive safety systems and plant designs previously developed for liquid-metal-cooled fast reactors, and (4) low-pressure liquid-salt coolants. The AHTR will require refueling, in-service inspection, and maintenance (RIM) with supporting instrumentation systems. The fluoride salts that are being evaluated as potential reactor coolants have melting points between 350 and 500 deg. C, values that imply minimum RIM temperatures between 400 and 550 deg. C. These salts are transparent over a wider range of the light spectrum than is water. The high temperatures, the optical characteristics of the coolant, and advances in metrology may enable the use of lasers to create three-dimensional images of the reactor interior to assist refueling, monitor vibrations in components, map fluid flow, and enable inspections of internal reactor components. A description of the reactor and an initial evaluation of the use of optical techniques for AHTR instrumentation are provided. (authors)

Forsberg, C. W. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831-6165 (United States); Varma, V. K.; Burgess, T. W. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831-6304 (United States)

2006-07-01T23:59:59.000Z

158

Method for reliability analysis of complex reactor systems. [LMFBR  

SciTech Connect (OSTI)

A method and a computer code for efficient and accurate reliability analyses of complex reactor systems are described and illustrated through an example. The method permits realistic analyses through its ability to accurately model and evaluate instantaneous and average unavailabilities for large systems with dependencies. The component models can include continuously monitored, non-repairable, and periodically tested components which are subject to failures resulting from components which are subject to failures resulting from component demands, stand-by conditions, human errors associated with testing and repair, as well as failures during actual operation. The numerical process used is efficient and allows analysis of general system configurations with arbitrary scheduling of maintenance operations.

Elerath, J.G.; Vaurio, J.K.; Wood, A.P.

1982-01-01T23:59:59.000Z

159

Reactivity control assembly for nuclear reactor. [LMFBR  

DOE Patents [OSTI]

This invention, which resulted from a contact with the United States Department of Energy, relates to a control mechanism for a nuclear reactor and, more particularly, to an assembly for selectively shifting different numbers of reactivity modifying rods into and out of the core of a nuclear reactor. It has been proposed heretofore to control the reactivity of a breeder reactor by varying the depth of insertion of control rods (e.g., rods containing a fertile material such as ThO/sub 2/) in the core of the reactor, thereby varying the amount of neutron-thermalizing coolant and the amount of neutron-capturing material in the core. This invention relates to a mechanism which can advantageously be used in this type of reactor control system.

Bollinger, L.R.

1982-03-17T23:59:59.000Z

160

New fast-reactor approach. [LMFBR  

SciTech Connect (OSTI)

The design parameters for a 1000 MW LMFBR type reactor are presented. The design requires the multiple primary coolant pumps and heat exchangers to be located around the core within the reactor vessel.

Folkrod, J.R.; Kann, W.J.; Klocksieben, R.H.

1983-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Audit Report - Naval Reactors Information Technology System Development Efforts, IG-0879  

Broader source: Energy.gov (indexed) [DOE]

Naval Reactors Information Naval Reactors Information Technology System Development Efforts DOE/IG-0879 December 2012 U.S. Department of Energy Office of Inspector General Office of Audits & Inspections Department of Energy Washington, DC 20585 December 21, 2012 MEMORANDUM FOR THE ADMINISTRATOR, NATIONAL NUCLEAR SECURITY ADMINISTRATION FROM: Gregory H. Friedman Inspector General SUBJECT: INFORMATION: Audit Report on the "Naval Reactors Information Technology System Development Efforts" INTRODUCTION AND OBJECTIVE The Naval Reactors Program (Naval Reactors), an organization within the National Nuclear Security Administration, was established to provide the military with safe and reliable nuclear propulsion plants to power warships and submarines. Naval Reactors maintains responsibility

162

Nuclear reactor downcomer flow deflector  

DOE Patents [OSTI]

A nuclear reactor having a coolant flow deflector secured to a reactor core barrel in line with a coolant inlet nozzle. The flow deflector redirects incoming coolant down an annulus between the core barrel and the reactor vessel. The deflector has a main body with a front side facing the fluid inlet nozzle and a rear side facing the core barrel. The rear side of the main body has at least one protrusion secured to the core barrel so that a gap exists between the rear side of the main body adjacent the protrusion and the core barrel. Preferably, the protrusion is a relief that circumscribes the rear side of the main body.

Gilmore, Charles B. (Greensburg, PA); Altman, David A. (Pittsburgh, PA); Singleton, Norman R. (Murrysville, PA)

2011-02-15T23:59:59.000Z

163

General features of direct-cycle, supercritical-pressure, light-water-cooled reactors  

SciTech Connect (OSTI)

The concept of direct-cycle, supercritical-pressure, light-water-cooled reactors is developed. Breeding is possible in the tight lattice core. The power output can be maximized in the fast converter reactor. The gross thermal efficiency of the high temperature reactor adopting Inconel as fuel cladding is expected to be 44.8%. The plant system is similar to the supercritical-fossil-fired power plant which adopts once-through type coolant circulation system. The volume and height of the containment are approximately half of the BWR. The basic safety principles follows those of LWRs. The reactor will solve the economic problems of LWR and LMFBR.

Oka, Y.; Koshizuka, S. [Univ. of Tokyo (Japan). Nuclear Engineering Research Lab.

1996-07-01T23:59:59.000Z

164

System for fuel rod removal from a reactor module  

DOE Patents [OSTI]

A robotic system for remote underwater withdrawal of the fuel rods from fuel modules of a light water breeder reactor includes a collet/grapple assembly for gripping and removing fuel rods in each module, which is positioned by use of a winch and a radial support means attached to a vertical support tube which is mounted over the fuel module. A programmable logic controller in conjunction with a microcomputer, provides control for the accurate positioning and pulling force of the rod grapple assembly. Closed circuit television cameras are provided which aid in operator interface with the robotic system. 7 figs.

Matchett, R.L.; Fodor, G.; Kikta, T.J.; Bacvinsicas, W.S.; Roof, D.R.; Nilsen, R.J.; Wilczynski, R.

1988-07-28T23:59:59.000Z

165

Ignition reactor and pump pulse parameters in a reactor–laser system  

Science Journals Connector (OSTI)

The experience gained in operating a demonstration nuclear-pumped laser in stand B (Physics and Power- Engineering Institute (FEI)) with a pulsed ignition reactor based on the 235U BARS-6 reactor is analyzed. It ...

P. P. D’yachenko; G. N. Fokin

2012-09-01T23:59:59.000Z

166

Nuclear plant-aging research on reactor protection systems  

SciTech Connect (OSTI)

This report presents the rsults of a review of the Reactor Trip System (RTS) and the Engineered Safety Feature Actuating System (ESFAS) operating experiences reported in Licensee Event Reports (LER)s, the Nuclear Power Experience data base, Nuclear Plant Reliability Data System, and plant maintenance records. Our purpose is to evaluate the potential significance of aging, including cycling, trips, and testing as contributors to degradation of the RTS and ESFAS. Tables are presented that show the percentage of events for RTS and ESFAS classified by cause, components, and subcomponents for each of the Nuclear Steam Supply System vendors. A representative Babcock and Wilcox plant was selected for detailed study. The US Nuclear Regulatory Commission's Nuclear Plant Aging Research guidelines were followed in performing the detailed study that identified materials susceptible to aging, stressors, environmental factors, and failure modes for the RTS and ESFAS as generic instrumentation and control systems. Functional indicators of degradation are listed, testing requirements evaluated, and regulatory issues discussed.

Meyer, L.C.

1988-01-01T23:59:59.000Z

167

Fast Reactor Subassembly Design Modifications for Increasing Electricity Generation Efficiency  

SciTech Connect (OSTI)

Suggested for Track 7: Advances in Reactor Core Design and In-Core Management _____________________________________________________________________________________ Fast Reactor Subassembly Design Modifications for Increasing Electricity Generation Efficiency R. Wigeland and K. Hamman Idaho National Laboratory Given the ability of fast reactors to effectively transmute the transuranic elements as are present in spent nuclear fuel, fast reactors are being considered as one element of future nuclear power systems to enable continued use and growth of nuclear power by limiting high-level waste generation. However, a key issue for fast reactors is higher electricity cost relative to other forms of nuclear energy generation. The economics of the fast reactor are affected by the amount of electric power that can be produced from a reactor, i.e., the thermal efficiency for electricity generation. The present study is examining the potential for fast reactor subassembly design changes to improve the thermal efficiency by increasing the average coolant outlet temperature without increasing peak temperatures within the subassembly, i.e., to make better use of current technology. Sodium-cooled fast reactors operate at temperatures far below the coolant boiling point, so that the maximum coolant outlet temperature is limited by the acceptable peak temperatures for the reactor fuel and cladding. Fast reactor fuel subassemblies have historically been constructed using a large number of small diameter fuel pins contained within a tube of hexagonal cross-section, or hexcan. Due to this design, there is a larger coolant flow area next to the hexcan wall as compared to flow area in the interior of the subassembly. This results in a higher flow rate near the hexcan wall, overcooling the fuel pins next to the wall, and a non-uniform coolant temperature distribution. It has been recognized for many years that this difference in sodium coolant temperature was detrimental to achieving greater thermal efficiency, since it causes the fuel pins in the center of the subassembly to operate at higher temperatures than those near the hexcan walls, and it is the temperature limit(s) for those fuel pins that limits the average coolant outlet temperature. Fuel subassembly design changes are being investigated using computational fluid dynamics (CFD) to quantify the effect that the design changes have on reducing the intra-subassembly coolant flow and temperature distribution. Simulations have been performed for a 19-pin test subassembly geometry using typical fuel pin diameters and wire wrap spacers. The results have shown that it may be possible to increase the average coolant outlet temperature by 20 C or more without changing the peak temperatures within the subassembly. These design changes should also be effective for reactor designs using subassemblies with larger numbers of fuel pins. R. Wigeland, Idaho National Laboratory, P.O. Box 1625, Mail Stop 3860, Idaho Falls, ID, U.S.A., 83415-3860 email – roald.wigeland@inl.gov fax (U.S.) – 208-526-2930

R. Wigeland; K. Hamman

2009-09-01T23:59:59.000Z

168

Development of alternate extractant systems for fast reactor fuel cycle  

SciTech Connect (OSTI)

Due to the limitations of TBP in processing of high burn-up, Pu-rich fast reactor fuels, there is a need to develop alternate extractants for fast reactor fuel processing. In this context, our Centre has been examining the suitability of alternate tri-alkyl phosphates. Third phase formation in the extraction of Th(IV) by TBP, tri-n-amyl phosphate (TAP) and tri-2-methyl-butyl phosphate (T2MBP) from nitric acid media has been investigated under various conditions to derive conclusions on their application for extraction of Pu at macro levels. The chemical and radiolytic degradation of tri-n-amyl-phosphate (TAP) diluted in normal paraffin hydrocarbon (NPH) in the presence of nitric acid has been investigated by the measurement of plutonium retention in organic phase. The potential application of room temperature ionic liquids (RTILs) for reprocessing of spent nuclear fuel has been explored. Extraction of uranium (VI) and palladium (II) from nitric acid medium by commercially available RTIL and tri-n-butyl phosphate solution in RTIL have been studied and the feasibility of electrodeposition of uranium as uranium oxide (UO{sub 2}) and palladium (II) as metallic palladium from the loaded organic phase have been demonstrated. This paper describes results of the above studies and discusses the suitability of the systems for fast reactor fuel reprocessing. (authors)

Vasudeva Rao, P.R.; Suresh, A.; Venkatesan, K.A.; Srinivasan, T.G.; Raj, Baldev [Indira Gandhi Centre for Atomic Research, Kalpakkam - 603 102 (India)

2007-07-01T23:59:59.000Z

169

Hybrid reliability model for nuclear reactor safety system  

Science Journals Connector (OSTI)

The dependability of critical safety systems needs to be quantitatively determined in order to verify their effectiveness, e.g. with regard to regulatory requirements. Since modular redundant safety systems are not required for normal operation, their reliability is strongly dependent on periodic inspection. Several modeling methods for the quantitative assessment of dependability are described in the literature, with a broad variation in complexity and modeling power. Static modeling techniques such as fault tree analysis (FTA) or reliability block diagrams (RBD) are not capable of capturing redundancy and repair or test activities. Dynamic state space based models such as continuous time Markov chains (CTMC) are more powerful but often result in very large, intractable models. Moreover, exponentially distributed state residence times are not a correct representation of actual residence times associated with repair activities or periodic inspection. In this study, a hybrid model combines a system level RBD with a CTMC to describe the dynamics. The effects of periodic testing are modeled by redistributing state probabilities at deterministic test times. Applying the method to the primary safety shutdown system of the BR2(Belgian Reactor 2)—nuclear research reactor, resulted in a quantitative as well as a qualitative assessment of its reliability.

Steven Verlinden; Geert Deconinck; Bernard Coupé

2012-01-01T23:59:59.000Z

170

Screening reactor steam/water piping systems for water hammer  

SciTech Connect (OSTI)

A steam/water system possessing a certain combination of thermal, hydraulic and operational states, can, in certain geometries, lead to a steam bubble collapse induced water hammer. These states, operations, and geometries are identified. A procedure that can be used for identifying whether an unbuilt reactor system is prone to water hammer is proposed. For the most common water hammer, steam bubble collapse induced water hammer, six conditions must be met in order for one to occur. These are: (1) the pipe must be almost horizontal; (2) the subcooling must be greater than 20 C; (3) the L/D must be greater than 24; (4) the velocity must be low enough so that the pipe does not run full, i.e., the Froude number must be less than one; (5) there should be void nearby; (6) the pressure must be high enough so that significant damage occurs, that is the pressure should be above 10 atmospheres. Recommendations on how to avoid this kind of water hammer in both the design and the operation of the reactor system are made.

Griffith, P. [Massachusetts Inst. of Tech., Cambridge, MA (United States)

1997-09-01T23:59:59.000Z

171

An autonomous long-term fast reactor system and the principal design limitations of the concept  

E-Print Network [OSTI]

Actinides MOX Mixed OXide MSR Molten-Salt Reactors NERI Nuclear Energy Research Initiative vii PWR Pressurized Water Reactor RGPu Reactor-Grade Plutonium SCNES Self-Consistent Nuclear Energy System STAR Secure Transportable Autonomous Reactor... of LWR?s, the drastic increase of Am and Cm inventories are observed after uranium fuel irradiation and the second recycling of MOX fuel.1 Therefore, partitioning and transmutation of the recovered MA?s could significantly reduce the long...

Tsvetkova, Galina Valeryevna

2004-09-30T23:59:59.000Z

172

Dynamic Impregnator Reactor System (Poster), NREL (National Renewable Energy Laboratory)  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Several unit operations are combined into Several unit operations are combined into one robust system, off ering fl exible and staged process confi gurations in one vessel. Spraying, soaking, low-severity pretreat- ment, enzymatic hydrolysis, fermentation, concentration/evaporation, and distillation are amongst its many capabilities. * 1,900 L Horizontal Paddle Blender Vessel with Sidewall Liquid Drains * 6-60 rpm / 50 HP Tri-Directional Agitator * 3.4 bar & Vacuum ASME Design, 316L Stainless Steel * Heating/Cooling Jacket using Water or Steam * 150 L Chemical Mix Tank & Pump with Spray Injectors * Vent Condenser with Collection Tank and Vacuum Pump Dynamic Impregnator Reactor System Multifaceted system designed for complex feedstock impregnation and processing Integrated Biorefi nery Research Facility | NREL * Golden, Colorado | December 15, 2011 | NREL/PO-5100-56156

173

Coil system for a mirror-based hybrid reactor  

SciTech Connect (OSTI)

Two different superconducting coil systems for the SFLM Hybrid study - a quadrupolar mirror based fusion-fission reactor study - are presented. One coil system is for a magnetic field with 2 T at the midplane and a mirror ratio of four. This coil set consists of semiplanar coils in two layers. The alternative coil system is for a downscaled magnetic field of 1.25 T at the midplane and a mirror ratio of four, where a higher {beta} is required to achieve sufficient the neutron production. This coil set has one layer of twisted 3D coils. The 3D coils are expected to be considerably cheaper than the semiplanar, since NbTi superconductors can be used for most coils instead of Nb3Sn due to the lower magnetic field.

Hagnestal, A.; Agren, O.; Moiseenko, V. E. [Uppsala University, Angstroem laboratory, Division of Electricity, Box 534, SE-751 21 Uppsala (Sweden); Institute of Plasma Physics, National Science Center 'Kharkov Institute of Physics and Technology', Akademichna st. 1, 61108 Kharkiv (Ukraine)

2012-06-19T23:59:59.000Z

174

Long-term serviceability of elastomers in modern engine coolants  

SciTech Connect (OSTI)

The aging of elastomers in engine coolants after extended periods of service can be both a physical process (stress/strain relaxation) and/or a chemical change. Engine coolants are essentially aqueous and non-aqueous electrolytes coupled with inorganic inhibitor systems, as well as new organic acid systems. The long-term effects of this environment are reviewed. Chemical and functional tests are utilized to model these aging processes. This review will offer a better understanding of the long-term suitability of typical candidate elastomers.

Bussem, H.; Farinella, A.C.; Hertz, D.L. Jr. [Seals Eastern Inc., Red Bank, NJ (United States)

1999-08-01T23:59:59.000Z

175

Chemical Looping Combustion System-Fuel Reactor Modeling  

SciTech Connect (OSTI)

Chemical looping combustion (CLC) is a process in which an oxygen carrier is used for fuel combustion instead of air or pure oxygen as shown in the figure below. The combustion is split into air and fuel reactors where the oxidation of the oxygen carrier and the reduction of the oxidized metal occur respectively. The CLC system provides a sequestration-ready CO2 stream with no additional energy required for separation. This major advantage places combustion looping at the leading edge of a possible shift in strict control of CO2 emissions from power plants. Research in this novel technology has been focused in three distinct areas: techno-economic evaluations, integration of the system into power plant concepts, and experimental development of oxygen carrier metals such as Fe, Ni, Mn, Cu, and Ca. Our recent thorough literature review shows that multiphase fluid dynamics modeling for CLC is not available in the open literature. Here, we have modified the MFIX code to model fluid dynamic in the fuel reactor. A computer generated movie of our simulation shows bubble behavior consistent with experimental observations.

Gamwo, I.K.; Jung, J. (ANL); Anderson, R.R.; Soong, Y.

2007-04-01T23:59:59.000Z

176

Development of mobile, on-site engine coolant recycling utilizing reverse-osmosis technology  

SciTech Connect (OSTI)

This paper presents the history of the development of self-contained, mobile, high-volume, engine coolant recycling by reverse osmosis (R/O). It explains the motivations, created by government regulatory agencies, to minimize the liability of waste generators who produce waste engine coolant by providing an engine coolant recycling service at the customer`s location. Recycling the used engine coolant at the point of origin minimizes the generators` exposure to documentation requirements, liability, and financial burdens by greatly reducing the volume of used coolant that must be hauled from the generator`s property. It describes the inherent difficulties of recycling such a highly contaminated, inconsistent input stream, such as used engine coolant, by reverse osmosis. The paper reports how the difficulties were addressed, and documents the state of the art in mobile R/O technology. Reverse osmosis provides a purified intermediate fluid that is reinhibited for use in automotive cooling systems. The paper offers a review of experiences in various automotive applications, including light-duty, medium-duty and heavy-duty vehicles operating on many types of fuel. The authors conclude that mobile embodiments of R/O coolant recycling technology provide finished coolants that perform equivalently to new coolants as demonstrated by their ability to protect vehicles from freezing, corrosion damage, and other cooling system related problems.

Kughn, W. [Toxguard Fluid Technologies, Irvine, CA (United States). CEO; Eaton, E.R. [Penray Companies, Inc., Elk Grove Village, IL (United States)

1999-08-01T23:59:59.000Z

177

Solar Thermochemical Advanced Reactor System, Wins R&D 100 Award...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

National Laboratory, the Solar Thermochemical Advanced Reactor System, or STARS, converts natural gas and sunlight into a more energy-rich fuel called syngas, which power plants...

178

Improved Design of Nuclear Reactor Control System | U.S. DOE...  

Office of Science (SC) Website

instrumentation: Improved Design of Nuclear Reactor Control System Developed at: Oak Ridge National Laboratory, Holifield Radioactive Ion Beam Facility (HRIBF) Developed...

179

A RESEARCH ON SEAMLESS PLATFORM CHANGE OF REACTOR PROTECTION SYSTEM FROM PLC TO FPGA  

E-Print Network [OSTI]

A RESEARCH ON SEAMLESS PLATFORM CHANGE OF REACTOR PROTECTION SYSTEM FROM PLC TO FPGA JUNBEOM YOO1 1. INTRODUCTION A safety grade PLC is an industrial digital computer used to develop safety-critical systems such as RPS (Reactor Protection System) for nuclear power plants. The software loaded into a PLC

180

Reliability analysis for Atucha II reactor protection system signals  

Science Journals Connector (OSTI)

Atucha II is a 745 MW Argentine Power Nuclear Reactor constructed by ENACE SA, Nuclear Argentine Company for Electrical Power Generation and SIEMENS AG KWU, Erlangen, Germany. A preliminary modular logic analysis of RPS (Reactor Protection System) signals was performed by means of the well known Swedish professional risk and reliability software named Risk-Spectrum taking as a basis a reference signal coded as JR17ER003 which command the two moderator loops valves. From the reliability and behavior knowledge for this reference signal folloos an estimation of the reliability for the other 97 RPS signals. Because the preliminary character of this analysis Main Important Measures are not performed at this stage. Reliability is by the statistic value named unavailability predicted. The scope of this analysis is restricted from the measurement elements to the RPS buffer outputs. In the present context only one redundancy is analyzed so in the Instrumentation and Control area there no CCF (Common Cause Failures) present for signals. Finally those unavailability values could be introduced in the failure domain for the posterior complete Atucha II reliability analysis which includes all mechanical and electromechanical features. Also an estimation of the spurious frequency of RPS signals defined as faulty by no trip is performed.

Jose Luis Roca

1996-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

System analysis study for Korean fusion DEMO reactor  

Science Journals Connector (OSTI)

A conceptual design study for a steady-state Korean fusion DEMO reactor (K-DEMO) has been initiated. Two peculiar features need to be noted. First, the major radius is designed to be just below 6.5 m, considering practical engineering feasibilities. But still, high magnetic field at the plasma center around 8 T is expected to be achieved by using current state-of-the-art high performance Nb3Sn strand technology. Second, a two-stage development plan is being considered. In the first stage, K-DEMO will demonstrate a net electricity generation but will also act as a component test facility. Then, after a major upgrade, K-DEMO is expected to show a net electric generation on the order of 300 MWe and the competitiveness in cost of electricity (COE). Feasibility of such a practical, near-future demonstration reactor is studied in this paper, based on a zero dimensional system analysis code study. It was shown that a net electric generation on the order of 300 MWe can be achieved below the optimistic ?N limit of 5. The elongation of K-DEMO is around 1.8 with single null configuration. Detailed optimization process and the resultant various plasma parameters are described.

Jun Ho Yeom; Keeman Kim; Young Seok Lee; Hyoung Chan Kim; Sangjun Oh; Kihak Im; Charles Kessel

2013-01-01T23:59:59.000Z

182

Physics of nuclear reactor safety  

Science Journals Connector (OSTI)

Provides a concise review of the physical aspects of safety of nuclear fission reactors. It covers the developments of roughly the last decade. The introductory chapter contains an analysis of the changes in safety philosophy that are characteristic of the last decade and that have given rise to an increased importance of physical aspects because of the emphasis on passive or natural safety. The second chapter focuses on the basics of reactor safety, identifying the main risk sources and the main principles for a safe design. The third chapter concerns a systematic treatment of the physical processes that are fundamental for the properties of fission chain reacting processes and the control of those processes. Because of the rather specialized nature of the field of reactor physics, each paragraph contains a very concise description of the theory of the phenomenon under consideration, before presenting a review of the developments. Chapter 4 contains a short review of the thermal aspects of reactor safety, restricted to those aspects that are characteristic of the nuclear reactor field, because thermal hydraulics of fission reactors is not principally different from that of other physical systems. In chapter 5 the consequences of the physics treated in the preceding chapters for the dynamics and safety of actual reactors are reviewed. The systematics of the treatment is mainly based on a division of reactors into three categories according to the type of coolant, which to a large extent determines the safety properties of the reactors. The last chapter contains a physical analysis of the Chernobyl accident that occurred in 1986. The reason for an attempt to give a review of this accident, as complete as possible within the space limits set by the editors, is twofold: the Chernobyl accident is the most severe accident in history and physical properties of the reactor played a decisive role, thereby serving as an illustration of the material of the preceding chapters.

H van Dam

1992-01-01T23:59:59.000Z

183

Testing of an advanced thermochemical conversion reactor system  

SciTech Connect (OSTI)

This report presents the results of work conducted by MTCI to verify and confirm experimentally the ability of the MTCI gasification process to effectively generate a high-quality, medium-Btu gas from a wider variety of feedstock and waste than that attainable in air-blown, direct gasification systems. The system's overall simplicity, due to the compact nature of the pulse combustor, and the high heat transfer rates attainable within the pulsating flow resonance tubes, provide a decided and near-term potential economic advantage for the MTCI indirect gasification system. The primary objective of this project was the design, construction, and testing of a Process Design Verification System for an indirectly heated, thermochemical fluid-bed reactor and a pulse combustor an an integrated system that can process alternative renewable sources of energy such as biomass, black liquor, municipal solid waste and waste hydrocarbons, including heavy oils into a useful product gas. The test objectives for the biomass portion of this program were to establish definitive performance data on biomass feedstocks covering a wide range of feedstock qualities and characteristics. The test objectives for the black liquor portion of this program were to verify the operation of the indirect gasifier on commercial black liquor containing 65 percent solids at several temperature levels and to characterize the bed carbon content, bed solids particle size and sulfur distribution as a function of gasification conditions. 6 refs., 59 figs., 29 tabs.

Not Available

1990-01-01T23:59:59.000Z

184

Computer simulation of magnetization-controlled shunt reactors for calculating electromagnetic transients in power systems  

SciTech Connect (OSTI)

A computer procedure for simulating magnetization-controlled dc shunt reactors is described, which enables the electromagnetic transients in electric power systems to be calculated. It is shown that, by taking technically simple measures in the control system, one can obtain high-speed reactors sufficient for many purposes, and dispense with the use of high-power devices for compensating higher harmonic components.

Karpov, A. S. [St Petersburg State Polytechnical University, JSC 'System Operator of the United Power System', Leningradskoe RDU (Russian Federation)] [St Petersburg State Polytechnical University, JSC 'System Operator of the United Power System', Leningradskoe RDU (Russian Federation)

2013-01-15T23:59:59.000Z

185

3D Neutronic Analysis in MHD Calculations at ARIES-ST Fusion Reactors Systems  

Science Journals Connector (OSTI)

...In this study, we developed new models for liquid wall (FW) state at ARIES-ST fusion reactor systems. ARIES-ST is a 1,000 MWe fusion reactor system based on a low aspect ratio ... simulation methods (ARIES Tea...

Aybaba Hançerliogullar?; Mesut Cini

2014-02-01T23:59:59.000Z

186

Tritium issues in commercial pressurized water reactors  

SciTech Connect (OSTI)

Tritium has become an important radionuclide in commercial Pressurized Water Reactors because of its mobility and tendency to concentrate in plant systems as tritiated water during the recycling of reactor coolant. Small quantities of tritium are released in routine regulated effluents as liquid water and as water vapor. Tritium has become a focus of attention at commercial nuclear power plants in recent years due to inadvertent, low-level, chronic releases arising from routine maintenance operations and from component failures. Tritium has been observed in groundwater in the vicinity of stations. The nuclear industry has undertaken strong proactive corrective measures to prevent recurrence, and continues to eliminate emission sources through its singular focus on public safety and environmental stewardship. This paper will discuss: production mechanisms for tritium, transport mechanisms from the reactor through plant, systems to the environment, examples of routine effluent releases, offsite doses, basic groundwater transport and geological issues, and recent nuclear industry environmental and legal ramifications. (authors)

Jones, G. [Constellation Energy Group, R.E. Ginna Nuclear Power Plant, Ontario, NY (United States)

2008-07-15T23:59:59.000Z

187

A long term radiological risk model for plutonium-fueled and fission reactor space nuclear system  

SciTech Connect (OSTI)

This report describes the optimization of the RISK III mathematical model, which provides risk assessment for the use of a plutonium-fueled, fission reactor in space systems. The report discusses possible scenarios leading to radiation releases on the ground; distinctions are made for an intact reactor and a dispersed reactor. Also included are projected dose equivalents for various accident situations. 54 refs., 31 figs., 11 tabs. (TEM)

Bartram, B.W.; Dougherty, D.K.

1987-01-01T23:59:59.000Z

188

Lunar electric power systems utilizing the SP?100 reactor coupled to dynamic conversion systems  

Science Journals Connector (OSTI)

An integration study was performed by Rocketdyne coupling an SP?100 reactor to either a Brayton Stirling or K?Rankine power conversion system. The application was for a surface power system to supply power requirements to a lunar base. A power level of 550 kWe was selected based on the National Aeronautics and Space Administration (NASA) Space Exploration Initiative 90?day study. Reliability studies were initially performed to determine optimum power conversion redundancy. This study resulted in selecting three operating engines and one standby unit. Integration design studies indicated that either of the three power conversion systems could be integrated with the SP?100 reactor. From a performance consideration the Brayton and Stirling mass was approximately 45% higher than the K?Rankine. The K?Rankine radiator area was 45% of the Stirling which in turn was about 40% of the Brayton.

Richard B. Harty; Gregory A. Johnson

1992-01-01T23:59:59.000Z

189

Preliminary requirements for a Fluoride Salt-Cooled High-Temperature Test Reactor (FHTR)  

SciTech Connect (OSTI)

A Fluoride Salt-Cooled High-Temperature Test Reactor (FHTR) design is being developed at MIT to provide the first demonstration and test of a salt-cooled reactor using high-temperature fuel. The first step is to define the requirements. The top level requirements are (1) provide the confidence that a larger demonstration reactor is warranted and (2) develop the necessary data for a larger-scale reactor. Because requirements will drive the design of the FHTR, a significant effort is being undertaken to define requirements and understand the tradeoffs that will be required for a practical design. The preliminary requirements include specifications for design parameters and necessary tests of major reactor systems. Testing requirements include demonstration of components, systems, and procedures for refueling, instrumentation, salt temperature control to avoid coolant freezing, salt chemistry and volume control, tritium monitoring and control, and in-service inspection. Safety tests include thermal hydraulics, neutronics - including intrinsic core shutdown mechanisms such as Doppler feedback - and decay heat removal systems. Materials and coolant testing includes fuels (including mechanical wear and fatigue) and system corrosion behavior. Preliminary analysis indicates a thermal power output below 30 MW, an initial core using pebble-bed or prismatic-block fuel, peak outlet temperatures of at least 700 deg. C, and use of FLi{sup 7}Be ({sup 7}LiF-BeF{sub 2}) coolant. The option to change-out the reactor core, fuel type, and major components is being investigated. While the FHTR will be used for materials testing, its primary mission is as a reactor system performance test to enable the design and licensing of a FHR demonstration power reactor. (authors)

Massie, M.; Forsberg, C.; Forget, B. [Dept. of Nuclear Science and Engineering, Massachusetts Inst. of Technology, Cambridge, MA 02139 (United States); Hu, L. W. [Nuclear Reactor Laboratory, Massachusetts Inst. of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States)

2012-07-01T23:59:59.000Z

190

Nuclear reactor control column  

DOE Patents [OSTI]

The nuclear reactor control column comprises a column disposed within the nuclear reactor core having a variable cross-section hollow channel and containing balls whose vertical location is determined by the flow of the reactor coolant through the column. The control column is divided into three basic sections wherein each of the sections has a different cross-sectional area. The uppermost section of the control column has the greatest cross-sectional area, the intermediate section of the control column has the smallest cross-sectional area, and the lowermost section of the control column has the intermediate cross-sectional area. In this manner, the area of the uppermost section can be established such that when the reactor coolant is flowing under normal conditions therethrough, the absorber balls will be lifted and suspended in a fluidized bed manner in the upper section. However, when the reactor coolant flow falls below a predetermined value, the absorber balls will fall through the intermediate section and into the lowermost section, thereby reducing the reactivity of the reactor core and shutting down the reactor.

Bachovchin, Dennis M. (Plum Borough, PA)

1982-01-01T23:59:59.000Z

191

Liquid metal systems development: reactor vessel support structure evaluation  

SciTech Connect (OSTI)

Results of an evaluation of support structures for the reactor vessel are reported. The U ring, box ring, integral ring, tee ring and tangential beam supports were investigated. The U ring is the recommended vessel support structure configuration.

McEdwards, J.A.

1981-01-01T23:59:59.000Z

192

Reactor Thermal-Hydraulics  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Thermal-Hydraulics Thermal-Hydraulics Dr. Tanju Sofu, Argonne National Laboratory In a power reactor, the energy produced in fission reaction manifests itself as heat to be removed by a coolant and utilized in a thermodynamic energy conversion cycle to produce electricity. A simplified schematic of a typical nuclear power plant is shown in the diagram below. Primary coolant loop Steam Reactor Heat exchanger Primary pump Secondary pump Condenser Turbine Water Although this process is essentially the same as in any other steam plant configuration, the power density in a nuclear reactor core is typically four orders of magnitude higher than a fossil fueled plant and therefore it poses significant heat transfer challenges. Maximum power that can be obtained from a nuclear reactor is often limited by the

193

Dynalene Fuel Cell Coolants Achieve Commercial Success | Department...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Dynalene Fuel Cell Coolants Achieve Commercial Success Dynalene Fuel Cell Coolants Achieve Commercial Success August 26, 2014 - 12:34pm Addthis Dynalene Inc. of Whitehall,...

194

Transient thermal analysis of a space reactor power system  

E-Print Network [OSTI]

Thermoelectric Power Conversion Module Heat Pipe Radiator Module . Auxiliary Modules . Flow of Calculation . Transient Test Cases Studied Summary . 10 10 CHAPTER II. ENERGY EQUATION FINITE DIFFERENCING . . 12 Energy Equation for a Solid Finite..., but this stud~ uses a generic liquid metal cooled fast reactor concept as the model to test the code. The space power svstem to be modeled consists of a liquid lithium cooled fast reactor, primarv and secondary loops svith a sell-induced thermoelectric...

Gaeta, Michael J.

1988-01-01T23:59:59.000Z

195

Hybrid energy systems (HESs) using small modular reactors (SMRs)  

SciTech Connect (OSTI)

Large-scale nuclear reactors are traditionally operated for a singular purpose: steady-state production of dispatchable baseload electricity that is distributed broadly on the electric grid. While this implementation is key to a sustainable, reliable energy grid, small modular reactors (SMRs) offer new opportunities for increased use of clean nuclear energy for both electric and thermal ap plications in more locations – while still accommodating the desire to support renewable production sources.

S. Bragg-Sitton

2014-10-01T23:59:59.000Z

196

ERANOS 2.1 : International Code System for GEN IV Fast Reactor Analysis  

SciTech Connect (OSTI)

The aim of the paper is to present the new release of the European Reactor Analysis Optimized code System, ERANOS 2.1. This version has been developed and validated to establish a suitable basis for reliable neutronic calculations of current, as well as advanced fast reactor cores of the GEN IV International Forum. The latest version of the ERANOS code and data system, ERANOS 2.1, contains all of the functions required for reference and design calculations of Liquid Metal Fast Reactors (LMFR's), with extended capabilities for treating advanced reactor fuel subassemblies and cores of Gas Cooled Fast Reactors (GCFR's). The releases of recent, modern neutron data libraries: JENDL-3.3 in 2002, JEFF-3.1 in 2005 and soon ENDF/B-VII are also available. (authors)

Ruggieri, J.M.; Tommasi, J.; Lebrat, J.F.; Suteau, C.; Plisson-Rieunier, D.; De Saint Jean, C.; Rimpault, G.; Sublet, J.C. [CEA/DEN/DER/SPRC/LEPH, CEA/Cadarache, 13108 Saint Paul Lez Durance, Cedex (France)

2006-07-01T23:59:59.000Z

197

Overview of environmental control aspects for the gas-cooled fast reactor  

SciTech Connect (OSTI)

Environmental control aspects relating to release of radionuclides have been analyzed for the Gas-Cooled Fast Reactor (GCFR). Information on environmental control systems was obtained for the most recent GCFR designs, and was used to evaluate the adequacy of these systems. The GCFR has been designed by the General Atomic Company as an alternative to other fast breeder reactor designs, such as the Liquid Metal Fast Breeder Reactor (LMFBR). The GCFR design includes mixed oxide fuel and helium coolant. The environmental impact of expected radionuclide releases from normal operation of the GCFR was evaluated using estimated collective dose equivalent commitments resulting from 1 year of plant operation. The results were compared to equivalent estimates for the Light Water Reactor (LWR) and High-Temperature Gas-Cooled Reactor (HTGR). A discussion of uncertainties in system performances, tritium production rates, and radiation quality factors for tritium is included.

Nolan, A.M.

1981-05-01T23:59:59.000Z

198

Solar Thermochemical Advanced Reactor System, Wins R&D 100 Award  

Office of Energy Efficiency and Renewable Energy (EERE)

Solar Thermochemical Advanced Reactor System, or STARS, converts natural gas and sunlight into a more energy-rich fuel called syngas, which power plants can burn to make electricity.

199

Power conversion system design for supercritical carbon dioxide cooled indirect cycle nuclear reactors  

E-Print Network [OSTI]

The supercritical carbon dioxide (S-CO?) cycle is a promising advanced power conversion cycle which couples nicely to many Generation IV nuclear reactors. This work investigates the power conversion system design and ...

Gibbs, Jonathan Paul

2008-01-01T23:59:59.000Z

200

Hanging core support system for a nuclear reactor  

DOE Patents [OSTI]

For holding the reactor core in the confining reactor vessel, a support is disclosed that is structurally independent of the vessel, that is dimensionally accurate and stable, and that comprises tandem tension linkages that act redundantly of one another to maintain stabilized core support even in the unlikely event of the complete failure of one of the linkages. The core support has a mounting platform for the reactor core, and unitary structure including a flange overlying the top edge of the reactor vessels, and a skirt and box beams between the flange and platform for establishing one of the linkages. A plurality of tension rods connect between the deck closing the reactor vessel and the platform for establishing the redundant linkage. Loaded Belleville springs flexibly hold the tension rods at the deck and separable bayonet-type connections hold the tension rods at the platform. Motion or radiation sensing detectors can be provide at the lower ends of the tension rods for obtaining pertinent readings proximate the core.

Burelbach, James P. (Glen Ellyn, IL); Kann, William J. (Park Ridge, IL); Pan, Yen-Cheng (Naperville, IL); Saiveau, James G. (Hickory Hills, IL); Seidensticker, Ralph W. (Wheaton, IL)

1987-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Predictive tools for coolant development: An accelerated aging procedure for modeling fleet test results  

SciTech Connect (OSTI)

The objective of this study was to develop an accelerated aging test (AAT) for conventional and extended life coolants that will predict coolant composition and performance after 100,000 or more miles (160,930 km) of use. The procedure was developed by examining the effects of a series of cooling system metals, their surface area and the amount of each used, test temperature, glycol concentration, and test time on important chemical and physical properties of the test coolant. The chemical and physical properties evaluated included the accumulation of glycol degradation products, the depletion rate of active inhibitors, the pH drop, and the presence of corrosion products in solution. In addition, the test coolant performance was evaluated in ASTM D 1384 and D 4340. The effects of variation in the test procedure on the coolant were compared to actual coolant from extended duration fleet tests. The test procedure selected gave test coolant with composition, physical properties, and performance that compared favorably with the fleet test fluid. The test performance was validated by comparing the properties of a series fluids after this test to corresponding fluids removed from vehicles after extended use. An example of fluid development using this procedure is presented. Further areas of investigation are suggested. It is recommended that the general test procedure be considered for adoption as an ASTM test method for evaluation of the extended performance of fluids in automotive and light duty cooling systems.

Gershun, A.V.; Mercer, W.C. [Prestone Products Corp., Danbury, CT (United States)

1999-08-01T23:59:59.000Z

202

System modeling for the advanced thermionic initiative single cell thermionic space nuclear reactor  

SciTech Connect (OSTI)

Incore thermionic space reactor design concepts which operate in a nominal power output range of 20 to 40 kWe are described. Details of the neutronics, thermionic, shielding, and heat rejection performance are presented. Two different designs, ATI-Driven and ATI-Driverless, are considered. Comparison of the core overall performance of these two configurations are described. The comparison of these two cores includes the overall conversion efficiency, reactor mass, shield mass, and heat rejection mass. An overall system design has been developed to model the advanced incore thermionic energy conversion based nuclear reactor systems for space applications in this power range.

Lee, H.H.; Lewis, B.R.; Klein, A.C. (Department of Nuclear Engineering, Oregon State University, Radiation Center, C116, Corvallis, Oregon 97331-5902 (United States)); Pawlowski, R.A. (Battelle Pacific Northwest Laboratories, Richland, Washington 99352 (United States))

1993-01-15T23:59:59.000Z

203

Numerical simulation of a blanket cooling system for fusion reactor based on PWR conditions  

Science Journals Connector (OSTI)

The simulations of a blanket cooling system were presented to address the choice of cooling channel geometry and coolant input data which are related to blanket engineering implementation. This work was performed using computer aided design (CAD) and computational fluid dynamics (CFD) technology. Simulations were carried out for the blanket module with a size of 0.6 m × 0.45 m in toroidal plane, and the nuclear heat was applied on the cooling system at Pn (neutron wall load) of 5 MW/m2. The structure factors and input data of hydraulics were investigated to explore the optimal parameters to match the PWR condition. It was found that the inlet velocity of first wall (FW) channel should be within the range of 2.48–3.34 m/s. As a result, the temperature rise (TR) of the coolant in the FW channel would be 24–25 K. This leads to the remaining space for TR within the range of 15 K in the piping circuits. It also indicated that the FW plays an important role in TR (reaches 60% of the whole cooling system) due to its high level of Pn and heat flux in the zones. It was predicted that the nuclear heat inside blanket module could be removed completely by the piping circuits with an acceptable pipe bore and the related input data. Finally, a possible design range of cooling parameters was proposed in view of engineering feasibility and blanket neutronics design.

Changle Liu; Jianzhong Zhang; Yinfeng Zhu; Songlin Liu; Xuebin Ma; Peiming Chen

2013-01-01T23:59:59.000Z

204

Status of fast-breeder-reactor safety  

SciTech Connect (OSTI)

The current state of knowledge of fast breeder reactors is reviewed. The primary focus on the analysis of postulated accident sequences and the implications to fast-reactor design. The accidents considered include loss-of-collant flow and transient overpower, both with a postulated failure to scram. The associated accident phenomena considered largely relate to the potential for energetic disassembly and include fuel, clad, and coolant motions during the accident sequence, fuel-coolant thermal interactions, and potential recriticality phenomena.

Avery, R.

1982-01-01T23:59:59.000Z

205

System pressure effect on the nuclear reactor limiting criterion. Revision 1  

SciTech Connect (OSTI)

The acceptable operating limits of a nuclear reactor are set to prevent fuel cladding damage. Critical Heat Flux (CHF) is the limiting criterion for the high pressure systems such as the BWRs (6.9 MPa) and the PWRs (13.8 MPa). However, the Onset of Flow Instability (OFI) is the limiting criterion of the low pressure system such as the existing Savannah River Site (SRS) production reactors (0.2 MPa). The physical basis of this difference is presented. 3 refs.

Chen, Kuo-Fu

1990-12-31T23:59:59.000Z

206

Thermal transfer structures coupling electronics card(s) to coolant-cooled structure(s)  

DOE Patents [OSTI]

Cooling apparatuses and coolant-cooled electronic systems are provided which include thermal transfer structures configured to engage with a spring force one or more electronics cards with docking of the electronics card(s) within a respective socket(s) of the electronic system. A thermal transfer structure of the cooling apparatus includes a thermal spreader having a first thermal conduction surface, and a thermally conductive spring assembly coupled to the conduction surface of the thermal spreader and positioned and configured to reside between and physically couple a first surface of an electronics card to the first surface of the thermal spreader with docking of the electronics card within a socket of the electronic system. The thermal transfer structure is, in one embodiment, metallurgically bonded to a coolant-cooled structure and facilitates transfer of heat from the electronics card to coolant flowing through the coolant-cooled structure.

David, Milnes P; Graybill, David P; Iyengar, Madhusudan K; Kamath, Vinod; Kochuparambil, Bejoy J; Parida, Pritish R; Schmidt, Roger R

2014-12-16T23:59:59.000Z

207

A future for nuclear energy: pebble bed reactors  

Science Journals Connector (OSTI)

Pebble Bed Reactors could allow nuclear plants to support the goal of reducing global climate change in an energy hungry world. They are small, modular, inherently safe, use a demonstrated nuclear technology and can be competitive with fossil fuels. Pebble bed reactors are helium cooled reactors that use small tennis ball size fuel balls consisting of only 9 grams of uranium per pebble to provide a low power density reactor. The low power density and large graphite core provide inherent safety features such that the peak temperature reached even under the complete loss of coolant accident without any active emergency core cooling system is significantly below the temperature that the fuel melts. This feature should enhance public confidence in this nuclear technology. With advanced modularity principles, it is expected that this type of design and assembly could lower the cost of new nuclear plants removing a major impediment to deployment.

Andrew C. Kadak

2005-01-01T23:59:59.000Z

208

Numerical procedure for calculating temperature profiles in LMFBR coolant channels  

SciTech Connect (OSTI)

A new numerical procedure (which makes use of a weighted residuals procedure in space and a fully-implicit finite difference procedure in time), for calculating temperatures in an LMFBR coolant channel has been developed and incorporated into the Super System Code (SSC). This procedure is highly accurate on a nodal basis and has greatly increased computational efficiency as compared to the method formerly in SSC.

Horak, W.C.; Kennett, R.J.; Guppy, J.G.

1981-07-01T23:59:59.000Z

209

Improved Design of Nuclear Reactor Control System | U.S. DOE Office of  

Office of Science (SC) Website

Improved Design of Nuclear Reactor Improved Design of Nuclear Reactor Control System Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff Archives SBIR/STTR Applications of Nuclear Science and Technology Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » Spinoff Archives Improved Design of Nuclear Reactor Control System Print Text Size: A A A RSS Feeds FeedbackShare Page Application/instrumentation: Improved Design of Nuclear Reactor Control System Developed at: Oak Ridge National Laboratory, Holifield Radioactive Ion Beam Facility (HRIBF)

210

Expert system for surveillance and diagnosis of breach fuel elements  

DOE Patents [OSTI]

An apparatus and method are disclosed for surveillance and diagnosis of breached fuel elements in a nuclear reactor. A delayed neutron monitoring system provides output signals indicating the delayed neutron activity and age and the equivalent recoil areas of a breached fuel element. Sensors are used to provide outputs indicating the status of each component of the delayed neutron monitoring system. Detectors also generate output signals indicating the reactor power level and the primary coolant flow rate of the reactor. The outputs from the detectors and sensors are interfaced with an artificial intelligence-based knowledge system which implements predetermined logic and generates output signals indicating the operability of the reactor.

Gross, Kenny C. (Lemont, IL)

1989-01-01T23:59:59.000Z

211

Heat insulating system for a fast reactor shield slab  

DOE Patents [OSTI]

Improved thermal insulation for a nuclear reactor deck comprising many helical coil springs disposed in generally parallel, side-by-side laterally overlapping or interfitted relationship to one another so as to define a three-dimensional composite having both metal and voids between the metal, and enclosure means for holding the composite to the underside of the deck.

Kotora, Jr., James (LaGrange Park, IL); Groh, Edward F. (Naperville, IL); Kann, William J. (Park Ridge, IL); Burelbach, James P. (Glen Ellyn, IL)

1986-01-01T23:59:59.000Z

212

Heat insulating system for a fast reactor shield slab  

DOE Patents [OSTI]

Improved thermal insulation for a nuclear reactor deck comprises many helical coil springs disposed in generally parallel, side-by-side laterally overlapping or interfitted relationship to one another so as to define a three-dimensional composite having both metal and voids between the metal, and enclosure means for holding the composite to the underside of the deck.

Kotora, J. Jr.; Groh, E.F.; Kann, W.J.; Burelbach, J.P.

1984-04-10T23:59:59.000Z

213

Performance of Liquid Metals in Natural Circulation Cooled Nuclear Reactors  

SciTech Connect (OSTI)

The inherent safety capability of natural circulation makes reactor design more reliable. Additionally, the construction and operation of a nuclear power plant with natural circulation in the primary cooling circuit is an interesting alternative for nuclear plant designers, due to their lower operational and investment costs obtained by simplifying systems and controls. This paper deals with the feasibility of application of natural circulation in the primary cooling circuit of a liquid metal fast reactor. The methodology employed is a non-dimensional analysis, which describes the relationship between the physical properties and system variables. The performance criterion is bounded by a safety argument, referring to the maximum cladding temperature allowed during operation. The study considers several coolants, which can play a part in reactor cooling systems, such as lead, lead-bismuth and sodium. Bismuth and gallium are included in this analysis, in order to extend the range of properties for reference purposes. The results present a characterization of natural circulation flow in a reactor and compare the cooling capabilities from different liquid metals coolants. (authors)

Ceballos, Carlos; Lathouwers, Danny; Verkooijen, Adrian [Interfacultair Reactor Instituut, Technische Universiteit Delft, Mekelweg 15, Delft (Netherlands)

2004-07-01T23:59:59.000Z

214

RELAP5/MOD3 code manual: Code structure, system models, and solution methods. Volume 1  

SciTech Connect (OSTI)

The RELAP5 code has been developed for best estimate transient simulation of light water reactor coolant systems during postulated accidents. The code models the coupled behavior of the reactor coolant system and the core for loss-of-coolant accidents, and operational transients, such as anticipated transient without scram, loss of offsite power, loss of feedwater, and loss of flow. A generic modeling, approach is used that permits simulating a variety of thermal hydraulic systems. Control system and secondary system components are included to permit modeling of plant controls, turbines, condensers, and secondary feedwater systems. RELAP5/MOD3 code documentation is divided into seven volumes: Volume I provides modeling theory and associated numerical schemes.

NONE

1995-08-01T23:59:59.000Z

215

Parametric study on maximum transportable distance and cost for thermal energy transportation using various coolants  

SciTech Connect (OSTI)

The operation temperature of advanced nuclear reactors is generally higher than commercial light water reactors and thermal energy from advanced nuclear reactor can be used for various purposes such as district heating, desalination, hydrogen production and other process heat applications, etc. The process heat industry/facilities will be located outside the nuclear island due to safety measures. This thermal energy from the reactor has to be transported a fair distance. In this study, analytical analysis was conducted to identify the maximum distance that thermal energy could be transported using various coolants such as molten-salts, helium and water by varying the pipe diameter and mass flow rate. The cost required to transport each coolant was also analyzed. The coolants analyzed are molten salts (such as: KClMgCl2, LiF-NaF-KF (FLiNaK) and KF-ZrF4), helium and water. Fluoride salts are superior because of better heat transport characteristics but chloride salts are most economical for higher temperature transportation purposes. For lower temperature water is a possible alternative when compared with He, because low pressure He requires higher pumping power which makes the process very inefficient and economically not viable for both low and high temperature application.

Su-Jong Yoon; Piyush Sabharwall

2014-07-01T23:59:59.000Z

216

Method and apparatus for enhancing reactor air-cooling system performance  

DOE Patents [OSTI]

An enhanced decay heat removal system for removing heat from the inert gas-filled gap space between the reactor vessel and the containment vessel of a liquid metal-cooled nuclear reactor. Multiple cooling ducts in flow communication with the inert gas-filled gap space are incorporated to provide multiple flow paths for the inert gas to circulate to heat exchangers which remove heat from the inert gas, thereby introducing natural convection flows in the inert gas. The inert gas in turn absorbs heat directly from the reactor vessel by natural convection heat transfer.

Hunsbedt, Anstein (Los Gatos, CA)

1996-01-01T23:59:59.000Z

217

Method and apparatus for enhancing reactor air-cooling system performance  

DOE Patents [OSTI]

An enhanced decay heat removal system is disclosed for removing heat from the inert gas-filled gap space between the reactor vessel and the containment vessel of a liquid metal-cooled nuclear reactor. Multiple cooling ducts in flow communication with the inert gas-filled gap space are incorporated to provide multiple flow paths for the inert gas to circulate to heat exchangers which remove heat from the inert gas, thereby introducing natural convection flows in the inert gas. The inert gas in turn absorbs heat directly from the reactor vessel by natural convection heat transfer. 6 figs.

Hunsbedt, A.

1996-03-12T23:59:59.000Z

218

Fossil-fuel processing technical/professional services: comparison of Fischer-Tropsch reactor systems. Phase I, final report  

SciTech Connect (OSTI)

The Fischer-Tropsch reaction was commercialized in Germany and used to produce military fuels in fixed bed reactors. It was recognized from the start that this reactor system had severe operating and yield limitations and alternative reactor systems were sought. In 1955 the Sasol I complex, using an entrained bed (Synthol) reactor system, was started up in South Africa. Although this reactor was a definite improvement and is still operating, the literature is filled with proponents of other reactor systems, each claiming its own advantages. This report provides a summary of the results of a study to compare the development potential of three of these reactor systems with the commercially operating Synthol-entrained bed reactor system. The commercial Synthol reactor is used as a benchmark against which the development potential of the other three reactors can be compared. Most of the information on which this study is based was supplied by the M.W. Kellogg Co. No information beyond that in the literature on the operation of the Synthol reactor system was available for consideration in preparing this study, nor were any details of the changes made to the original Synthol system to overcome the operating problems reported in the literature. Because of conflicting claims and results found in the literature, it was decided to concentrate a large part of this study on a kinetic analysis of the reactor systems, in order to provide a theoretical analysis of intrinsic strengths and weaknesses of the reactors unclouded by different catalysts, operating conditions and feed compositions. The remainder of the study considers the physical attributes of the four reactor systems and compares their respective investment costs, yields, catalyst requirements and thermal efficiencies from simplified conceptual designs.

Thompson, G.J.; Riekena, M.L.; Vickers, A.G.

1981-09-01T23:59:59.000Z

219

Copper-triazole interaction and coolant inhibitor depletion  

SciTech Connect (OSTI)

To a large extent, the depletion of tolyltriazole (TTZ) observed in several field tests may be attributed to the formation of a protective copper-triazole layer. Laboratory aging studies, shown to correlate with field experience, reveal that copper-TTZ layer formation depletes coolant TTZ levels in a fashion analogous to changes observed in the field. XPS and TPD-MS characterization of the complex formed indicates a strong chemical bond between copper and the adsorbed TTZ which can be desorbed thermally only at elevated temperatures. Electrochemical polarization experiments indicate that the layer provides good copper protection even when TTZ is absent from the coolant phase. Examination of copper cooling system components obtained after extensive field use reveals the presence of a similar protective layer.

Bartley, L.S.; Fritz, P.O.; Pellet, R.J.; Taylor, S.A.; Van de Ven, P. [Texaco Fuels and Lubricants Technology Dept., Beacon, NY (United States)

1999-08-01T23:59:59.000Z

220

Recycling used engine coolant using high-volume stationary, multiple technology equipment  

SciTech Connect (OSTI)

Recycling used engine coolant has become increasingly desirable due to two significant factors. First, engine coolant frequently merits designation as a hazardous waste under the Federal Clean Water Act. Federal and some state environmental protection agencies have instituted strict regulation of the disposal of used engine coolant. In some cases, the disposal of engine coolant requires imposition of waste disposal fees and surcharges. Secondly, ethylene glycol, the principal cost component of engine coolant, has experienced dramatic price fluctuations and occasional shortages in supply. Therefore, there are both environmental and economic pressures to recycle engine coolant and recover the ethylene glycol component in an efficient and cost-effective manner. This paper discusses a multistage apparatus and a process for recycling used engine coolant that employs a combination of filtration, centrifugation (hydrocyclone separation), dissolved air flotation, nanofiltration, reverse osmosis, continuous deionization, and ion exchange processes for separating ethylene glycol and water from used engine coolant. The engine coolant is prefiltered through a series of filters. The filters remove particulate contaminates. This filtered fluid is then subjected to dissolved air flotation and centrifugation to remove petroleum. Then it is heated and pressurized prior to being passed over a series of two different sets of semipermeable membranes. The membrane technologies separate the feed stream into a permeate solution of ethylene glycol and water and a concentrate waste solution. The concentrate solution is returned to a concentrate tank for continuous circulation through the apparatus. The permeate solution is subjected to final refining by continuous deionization followed by a cation and anion ion exchange polishing process. The continuous deionization reduces ionic contaminants, and the ion exchange system eliminates any ionic contaminants left by the previous purification methods. A mechanical blender is used to mix the purified recovered fluid with fresh ethylene glycol (to adjust freeze point) and performance enhancing chemicals.

Haddock, M.E. [Recycled Engine Coolants, Inc., Austin, TX (United States); Eaton, E.R. [Penray Companies, Inc., Elk Grove Village, IL (United States)

1999-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Dual annular rotating [open quotes]windowed[close quotes] nuclear reflector reactor control system  

DOE Patents [OSTI]

A nuclear reactor control system is provided in a nuclear reactor having a core operating in the fast neutron energy spectrum where criticality control is achieved by neutron leakage. The control system includes dual annular, rotatable reflector rings. There are two reflector rings: an inner reflector ring and an outer reflector ring. The reflectors are concentrically assembled, surround the reactor core, and each reflector ring includes a plurality of openings. The openings in each ring are capable of being aligned or non-aligned with each other. Independent driving means for each of the annular reflector rings is provided so that reactor criticality can be initiated and controlled by rotation of either reflector ring such that the extent of alignment of the openings in each ring controls the reflection of neutrons from the core. 4 figures.

Jacox, M.G.; Drexler, R.L.; Hunt, R.N.M.; Lake, J.A.

1994-03-29T23:59:59.000Z

222

Lessons Learned From Gen I Carbon Dioxide Cooled Reactors  

SciTech Connect (OSTI)

This paper provides a review of early gas cooled reactors including the Magnox reactors originating in the United Kingdom and the subsequent development of the Advanced Gas-cooled Reactors (AGR). These early gas cooled reactors shared a common coolant medium, namely carbon dioxide (CO2). A framework of information is provided about these early reactors and identifies unique problems/opportunities associated with use of CO2 as a coolant. Reactor designers successfully rose to these challenges. After years of successful use of the CO2 gas cooled reactors in Europe, the succeeding generation of reactors, called the High Temperature Gas Reactors (HTGR), were designed with Helium gas as the coolant. Again, in the 21st century, with the latest reactor designs under investigation in Generation IV, there is a revived interest in developing Gas Cooled Fast Reactors that use CO2 as the reactor coolant. This paper provides a historical perspective on the 52 CO2 reactors and the reactor programs that developed them. The Magnox and AGR design features and safety characteristics were reviewed, as well as the technologies associated with fuel storage, reprocessing, and disposal. Lessons-learned from these programs are noted to benefit the designs of future generations of gas cooled nuclear reactors.

David E. Shropshire

2004-04-01T23:59:59.000Z

223

Knowledge base expert system control of spatial xenon oscillations in pressurized water reactors  

Science Journals Connector (OSTI)

Current xenon oscillation control methods used in pressurized water reactors are knowledge intensive, and heuristic in nature. An expert system is developed to implement the heuristic constant axial offset control procedure to aid reactor operators in increasing the plant reliability by reducing the human error component of the failure probability. An expert system is written in the production system language, OPS5, with a forward chaining algorithm. It samples the reactor core with a certain time interval, evaluates the core status to determine the necessary corrective actions in terms of reactivity insertion, and selects the control parameter to realize this reactivity insertion. The amount of control action is determined using a knowledge base which consists of the differential rod worth curves, and the boron reactivity worth of a given reactor. The controller has been tested using a one-dimesional core model for verification of the rules and the code. It has been shown that, having the reactor dependent parameters in its knowledge base, the controller is able to follow a typical load demand for a daily cycle of a reactor, and is able to keep the axial offset within a target band.

Serhat Alten; Richard A Danofsky

1993-01-01T23:59:59.000Z

224

Analysis of thermal self-maintained oscillation mechanism in the thermionic reactor-converter with multielement TFE's  

SciTech Connect (OSTI)

Thermal self-maintained oscillations are found in the TOPAZ reactor. These are caused by periodical boiling of the coolant in sections of separate channels. (AIP)

Zrodnikov, A.V.; Pupko, V.Y.; Semenisty, V.L. (Institute of Physics Power Engineering, 249020 Obninsk, USSR (SU))

1991-01-05T23:59:59.000Z

225

Transcript of "Laparoscopic Partial Nephrectomy with Ice Slurry as Coolant  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

ESE | NE | Site Index | Contact us | Help | Privacy/Security ESE | NE | Site Index | Contact us | Help | Privacy/Security Notice Home > Capabilities > Biomedical Applications > Medical Ice Slurry Coolants > Laparoscopic Partial Nephrectomy with Ice Slurry as Coolant in the Porcine Model > Transcript The Multimedia Collection Laparoscopic Partial Nephrectomy with Ice Slurry as Coolant in the Porcine Model Laparoscopic Partial Nephrectomy with Ice Slurry as Coolant in the Porcine Model VIDEO TRANSCRIPT Achieving optimal hypothermia of the kidney during laparoscopic partial nephrectomy remains a challenge and also an obstacle for wide-spread adoption of this technique for nephron-sparing surgery. Other approaches for renal cooling such as perfusion of the renal collecting system or vasculature with cold saline are either ineffective or cumbersome. In this study we assess the application of ice slurry as kidney cooling during laparoscopic partial nephrectomy in the porcine model. This study was performed in collaboration with Argonne National Laboratory.

226

B Reactor | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Operational Management » History » Manhattan Project » Signature Operational Management » History » Manhattan Project » Signature Facilities » B Reactor B Reactor B Reactor Completed in September 1944, the B Reactor was the world's first large-scale plutonium production reactor. As at Oak Ridge, the need for labor turned Hanford into an atomic boomtown, with the population reaching 50,000 by summer 1944. Similar to the X-10 Graphite Reactor at Oak Ridge in terms of loading and unloading fuel, the B Reactor was built on a much larger scale and used water rather than air as a coolant. Whereas the X-10 had an initial design output of 1,000 kilowatts, the B Reactor was designed to operate at 250,000 kilowatts. Consisting of a 28- by 36-foot, 1,200-ton graphite cylinder lying on its side, the reactor was penetrated through its

227

Enhancing VHTR passive safety and economy with thermal radiation based direct reactor auxiliary cooling system  

SciTech Connect (OSTI)

One of the most important requirements for Gen. IV Very High Temperature Reactor (VHTR) is passive safety. Currently all the gas cooled version of VHTR designs use Reactor Vessel Auxiliary Cooling System (RVACS) for passive decay heat removal. The RVACS can be characterized as a surface-based decay heat removal system. It is especially suitable for smaller power reactors since small systems have relatively larger surface area to volume ratio. However, RVACS limits the maximum achievable power level for modular VHTRs due to the mismatch between the reactor power (proportional to the core volume) and decay heat removal capability (proportional to the vessel surface area). Besides the safety considerations, VHTRs also need to be economical in order to compete with other reactor concepts and other types of energy sources. The limit of decay heat removal capability set by using RVACS has affected the economy of VHTRs. A potential alternative solution is to use a volume-based passive decay heat removal system, called Direct Reactor Auxiliary Cooling Systems (DRACS), to remove or mitigate the limitation on decay heat removal capability. DRACS composes of natural circulation loops with two sets of heat exchangers, one on the reactor side and another on the environmental side. For the reactor side, cooling pipes will be inserted into holes made in the outer or inner graphite reflector blocks. There will be gaps or annular regions formed between these cooling pipes and their corresponding surrounding graphite surfaces. Graphite has an excellent heat conduction property. By taking advantage of this feature, we can have a volume-based method to remove decay heat. The scalability can be achieved, if needed, by employing more rows of cooling pipes to accommodate higher decay heat rates. Since heat can easily conduct through the graphite regions among the holes made for the cooling pipes, those cooling pipes located further away from the active core region can still be very effective in removing decay heat. By removing the limit on the decay heat removal capability due to the limited available surface area as in a RVACS, the reactor power density and therefore the reactor power can be significantly increased, without losing the passive heat removal feature. This paper introduces the concept of using DRACS to enhance VHTR passive safety and economics. Three design options with different cooling pipe locations are discussed. Analysis results from a lumped volume based model and CFD simulations are presented. (authors)

Zhao, H.; Zhang, H.; Zou, L. [Idaho National Laboratory (United States); Sun, X. [Ohio State Univ. (United States)

2012-07-01T23:59:59.000Z

228

Fleet test evaluations of an automotive and medium-duty truck coolant filter conditioner  

SciTech Connect (OSTI)

The use of coolant filtration and supplemental coolant additives (SCA) to replenish depleted protective chemistry has been applied in the heavy duty diesel arena for many years. Some filtration of coolant and SCA usage in light gasoline engine and automotive diesel engine vehicles has taken place using off-board equipment to filter and recondition coolant. As concerns about the environment have increased, disposal of spent coolant that is replaced on a scheduled basis is a burden on fleets as well as individuals. In addition, as the efforts by vehicle manufacturers to extend or eliminate routine service intervals of vehicle systems increase, the use of an on-board system has become more attractive. A number of filtration/conditioning designs have been developed for light and medium duty use and have been on field tests for over a year. These field tests are described and reported, along with background on the filter design and chemistry package used. Field testing included: low and high mileage vehicles; newer and older vehicles; well and poorly maintained vehicles; and an assessment of the possibility of overcharging of the coolant chemistry.

Wright, A.B. [AlliedSignal Filters and Spark Plugs, Perrysburg, OH (United States)

1999-08-01T23:59:59.000Z

229

Reliability analysis of a passive cooling system using a response surface with an application to the Flexible Conversion Ratio Reactor .  

E-Print Network [OSTI]

??A comprehensive risk-informed methodology for passive safety system design and performance assessment is presented and demonstrated on the Flexible Conversion Ratio Reactor (FCRR). First, the… (more)

Fong, Christopher J. (Christopher Joseph)

2008-01-01T23:59:59.000Z

230

Wastewater Effluent Polishing Systems of Anaerobic Baffled Reactor Treating Black-water from Households  

E-Print Network [OSTI]

Wastewater Effluent Polishing Systems of Anaerobic Baffled Reactor Treating Black-water from of different integrated low-cost wastewater treatment systems, comprising one ABR as first treatment step filter and a vertical flow constructed wetland. A mixture of septage and domestic wastewater was used

Richner, Heinz

231

A HYBRID ADSORBENT-MEMBRANE REACTOR (HAMR) SYSTEM FOR HYDROGEN PRODUCTION  

E-Print Network [OSTI]

hydrogen production for proton exchange membrane (PEM) fuel cells for various mobile and stationaryA HYBRID ADSORBENT-MEMBRANE REACTOR (HAMR) SYSTEM FOR HYDROGEN PRODUCTION A. Harale, H. Hwang, P recently our focus has been on new HAMR systems for hydrogen production, of potential interest to pure

Southern California, University of

232

Estimation of coolant void reactivity for CANDU-NG lattice using DRAGON and validation using MCNP5 and TRIPOLI-4.3  

SciTech Connect (OSTI)

The Coolant Void Reactivity (CVR) is an important safety parameter that needs to be estimated at the design stage of a nuclear reactor. It helps to have an a priori knowledge of the behavior of the system during a transient initiated by the loss of coolant. In the present paper, we have attempted to estimate the CVR for a CANDU New Generation (CANDU-NG) lattice, as proposed at an early stage of the Advanced CANDU Reactor (ACR) development. We have attempted to estimate the CVR with development version of the code DRAGON, using the method of characteristics. DRAGON has several advanced self-shielding models incorporated in it, each of them compatible with the method of characteristics. This study will bring to focus the performance of these self-shielding models, especially when there is voiding of such a tight lattice. We have also performed assembly calculations in 2 x 2 pattern for the CANDU-NG fuel, with special emphasis on checkerboard voiding. The results obtained have been validated against Monte Carlo codes MCNP5 and TRIPOLI-4.3. (authors)

Karthikeyan, R.; Tellier, R. L.; Hebert, A. [Ecole Polytechnique de Montreal, 2900 Boulevard Edouard-Montpetit, Montreal, Que. H3T 1J4 (Canada)

2006-07-01T23:59:59.000Z

233

Behavior of 241Am in fast reactor systems - a safeguards perspective  

SciTech Connect (OSTI)

Advanced fuel-cycle developments around the world currently under development are exploring the possibility of disposing of {sup 241}Am from spent fuel recycle processes by burning this material in fast reactors. For safeguards practitioners, this approach could potentially complicate both fresh- and spent-fuel safeguards measurements. The increased ({alpha},n) production in oxide fuels from the {sup 241}Am increases the uncertainty in coincidence assay of Pu in MOX assemblies and will require additional information to make use of totals-based neutron assay of these assemblies. We have studied the behavior of {sup 241}Am-bearing MOX fuel in the fast reactor system and the effect on neutron and gamma-ray source-terms for safeguards measurements. In this paper, we will present the results of simulations of the behavior of {sup 241}Am in a fast breeder reactor system. Because of the increased use of MOX fuel in thermal reactors and advances in fuel-cycle designs aimed at americium disposal in fast reactors, we have undertaken a brief study of the behavior of americium in these systems to better understand the safeguards impacts of these new approaches. In this paper we will examine the behavior of {sup 241}Am in a variety of nuclear systems to provide insight into the safeguards implications of proposed Am disposition schemes.

Beddingfield, David H [Los Alamos National Laboratory; Lafleur, Adrienne M [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

234

Experiment operations plan for the TH-2 experiment in the NRU reactor. [PWR; BWR  

SciTech Connect (OSTI)

A series of thermal-hydraulic and cladding materials deformation experiments were conducted using light-water reactor fuel bundles as part of the Pacific Northwest Laboratory Loss-of-Coolant Accident (LOCA) Simulation Program. This report is the formal operations plan for TH-2--the second experiment in the series of thermal-hydraulic tests conducted in the National Research Universal (NRU) reactor, Chalk River, Ontario, Canada. The major objective of TH-2 was to develop the experiment reflood control parameters and the procedures to be used in subsequent experiments in this program. In this experiment, the data acquisition and control system was used to control the fuel cladding temperature during a simulated LOCA by using variable reflood coolant flow.

Russcher, G.E.; Wilson, C.L.; Parchen, L.J.; Freshley, M.D.

1983-06-01T23:59:59.000Z

235

The results of systems tests of the 500 kV busbar controllable shunting reactor in the Tavricheskaya substation  

SciTech Connect (OSTI)

The results of systems tests of the 500 kV busbar magnetization-controllable shunting reactor (CSR), set up in the Tavricheskaya substation, including measurements of the quality of the electric power, the harmonic composition of the network currents of the reactor for different values of the reactive power consumed, the determination of the regulating characteristics of the reactor, the speed of response of the shunting reactor in the current and voltage stabilization modes, and also the operation of the reactor under dynamic conditions for different perturbations, are presented. The results obtained are analyzed.

Gusev, S. I. [JSC 'FSK EES' (Russian Federation); Karpov, V. N.; Kiselev, A. N.; Kochkin, V. I. [Scientific-Research Institute of Electric Power Engineering (VNIIE) - Branch of the JSC 'NTTs Elektroenergetiki', (Russian Federation)

2009-09-15T23:59:59.000Z

236

Major Safety Aspects of Advanced Candu Reactor and Associated Research and Development  

SciTech Connect (OSTI)

The Advanced Candu{sup R} Reactor design is built on the proven technology of existing Candu plants and on AECL's knowledge base acquired over decades of nuclear power plant design, engineering, construction and research. Two prime objectives of ACR-700TM1 are cost reduction and enhanced safety. To achieve them some new features were introduced and others were improved from the previous Candu 6 and Candu 9 designs. The ACR-700 reactor design is based on the modular concept of horizontal fuel channels surrounded by a heavy water moderator, the same as with all Candu reactors. The major novelty in the ACR-700 is the use of slightly enriched fuel and light water as coolant circulating in the fuel channels. This results in a more compact reactor design and a reduction of heavy water inventory, both contributing to a significant decrease in cost compared to Candu reactors, which employ natural uranium as fuel and heavy water as coolant. The reactor core design adopted for ACR-700 also has some features that have a bearing on inherent safety, such as negative power and coolant void reactivity coefficient. Several improvements in engineered safety have been made as well, such as enhanced separation of the safety support systems. Since the ACR-700 design is an evolutionary development of the currently operating Candu plants, limited research is required to extend the validation database for the design and the supporting safety analysis. A program of safety related research and development has been initiated to address the areas where the ACR-700 design is significantly different from the Candu designs. This paper describes the major safety aspects of the ACR-700 with a particular focus on novel features and improvements over the existing Candu reactors. It also outlines the key areas where research and development efforts are undertaken to demonstrate the effectiveness and robustness of the design. (authors)

Bonechi, M.; Wren, D.J.; Hopwood, J.M. [Atomic Energy of Canada Limited, 2251 Speakman Drive, Mississauga, Ontario, L5K 1B2 (Canada)

2002-07-01T23:59:59.000Z

237

Reactor Safety Research Programs Quarterly Report October - December 1981  

SciTech Connect (OSTI)

This document summarizes the work performed by Pacific Northwest laboratory (PNL) from October 1 through December 31, 1981, for the Division of Accident Evaluation, U.S. Nuclear Regulatory Commission (NRC). Evaluations of nondestructive examination (NDE) techniques and instrumentation are reported; areas of investigation include demonstrating the feasibility of determining the strength of structural graphite, evaluating the feasibility of detecting and analyzing flaw growth in reactor pressure boundary systems, examining NDE reliability and probabilistic fracture mechanics, and assessing the integrity of pressurized water reactor (PWR) steam generator tubes where serviceinduced degradation has been indicated. Experimental data and analytical models are being provided to aid in decision-making regarding pipe-to-pipe impacts following postulated breaks in high-energy fluid system piping. Core thermal models are being developed to provide better digital codes to compute the behavior of full-scale reactor systems under postulated accident conditions. Fuel assemblies and analytical support are being provided for experimental programs at other facilities. These programs include loss-of-coolant accident (LOCA) simulation tests at the NRU reactor, Chalk River, Canada; fuel rod deformation, severe fuel damage, and post accident coolability tests for the ESSOR reactor Super Sara Test Program, lspra, Italy; the instrumented fuel assembly irradiation program at Halden, Norway; and experimental programs at the Power Burst Facility, Idaho National Engineering Laboratory (INEL), Idaho Falls, Idaho. These programs will provide data for computer modeling of reactor system and fuel performance during various abnormal operating conditions.

Edler, S. K.

1982-03-01T23:59:59.000Z

238

Small break LOCA analysis of the ONRL high flux isotope reactor  

SciTech Connect (OSTI)

A digital simulation program, HFIRSYS, was developed using MMS to analyze small break loss of coolant events in the ORNL High Flux Isotope Reactor. The code evaluates the response of the primary reactor system including automatic controls actions resulting from breaks in auxiliary piping connected to the primary. The primary output of the code is the margin to the onset of nucleate boiling expressed as a ratio of heat flux which would cause boiling to the current hot channel heat flux. A description of the model, validation results and a sample transient are presented.

Wilson, T.L. Jr.; Cook, D.H.; Sozer, A.

1988-01-01T23:59:59.000Z

239

Development of an extended-service coolant filter  

SciTech Connect (OSTI)

An extended-service engine coolant filter has been developed, using conventional supplemental coolant additive (SCA) technology. This has been achieved by the use of a proprietary polymer coating, which delays the release of active engine coolant chemistry. Initial field data show a gradual release pattern for introducing SCA chemistry into the coolant, with complete release typically occurring in the range of 70,000 to 140,000 miles (112,651--225,302 km).

Mitchell, W.A. [BetzDearborn, Crystal Lake, IL (United States). Venture Activities Group; Hudgens, R.D. [Fleetguard/Nelson Inc., Cookeville, TN (United States)

1999-08-01T23:59:59.000Z

240

Westinghouse Small Modular Reactor balance of plant and supporting systems design  

SciTech Connect (OSTI)

The Westinghouse Small Modular Reactor (SMR) is an 800 MWt (>225 MWe) integral pressurized water reactor (iPWR), in which all of the components typically associated with the nuclear steam supply system (NSSS) of a nuclear power plant are incorporated within a single reactor pressure vessel. This paper is the second in a series of four papers which describe the design and functionality of the Westinghouse SMR. It focuses, in particular, upon the supporting systems and the balance of plant (BOP) designs of the Westinghouse SMR. Several Westinghouse SMR systems are classified as safety, and are critical to the safe operation of the Westinghouse SMR. These include the protection and monitoring system (PMS), the passive core cooling system (PXS), and the spent fuel cooling system (SFS) including pools, valves, and piping. The Westinghouse SMR safety related systems include the instrumentation and controls (I and C) as well as redundant and physically separated safety trains with batteries, electrical systems, and switch gears. Several other incorporated systems are non-safety related, but provide functions for plant operations including defense-in-depth functions. These include the chemical volume control system (CVS), heating, ventilation and cooling (HVAC) systems, component cooling water system (CCS), normal residual heat removal system (RNS) and service water system (SWS). The integrated performance of the safety-related and non-safety related systems ensures the safe and efficient operation of the Westinghouse SMR through various conditions and transients. The turbine island consists of the turbine, electric generator, feedwater and steam systems, moisture separation systems, and the condensers. The BOP is designed to minimize assembly time, shipping challenges, and on-site testing requirements for all structures, systems, and components. (authors)

Memmott, M. J.; Stansbury, C.; Taylor, C. [Westinghouse Electric Company LLC, 600 Cranberry Woods Drive, Cranberry Twp. PA 16066 (United States)

2012-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Reliable-linac design for accelerator-driven subcritical reactor systems.  

SciTech Connect (OSTI)

Accelerator reliability corresponding to a very low frequency of beam interrupts is an important new accelerator requirement for accelerator-driven subcritical reactor systems. In this paper we review typical accelerator-reliability requirements and discuss possible methods for meeting these goals with superconducting proton-linac technology.

Wangler, Thomas P.,

2002-01-01T23:59:59.000Z

242

ITM Syngas and ITM H2: Engineering Development of Ceramic Membrane Reactor Systems for  

E-Print Network [OSTI]

(U.S. DOE) and other members of the ITM Syngas/ITM H2 Team, is developing Ion Transport Membrane (ITM of the ITM membrane to oxygen ions, which diffuse through the membrane under a chemical potential gradientITM Syngas and ITM H2: Engineering Development of Ceramic Membrane Reactor Systems for Converting

243

The development of a remote monitoring system for the Nuclear Science Center reactor  

E-Print Network [OSTI]

remote access to data from the reactor site is an important part of this project. The two goals of this monitoring system are to control the use of nuclear materials and to monitor the performance of the facility from a remote location. I have designed a...

Jiltchenkov, Dmitri Victorovich

2012-06-07T23:59:59.000Z

244

Space reactor/Stirling cycle systems for high power Lunar applications  

SciTech Connect (OSTI)

NASA`s Space Exploration Initiative (SEI) has proposed the use of high power nuclear power systems on the lunar surface as a necessary alternative to solar power. Because of the long lunar night ({approximately} 14 earth days) solar powered systems with the requisite energy storage in the form of regenerative fuel cells or batteries becomes prohibitively heavy at high power levels ({approximately} 100 kWe). At these high power levels nuclear power systems become an enabling technology for variety of missions. One way of producing power on the lunar surface is with an SP-100 class reactor coupled with Stirling power converters. In this study, analysis and characterization of the SP-100 class reactor coupled with Free Piston Stirling Power Conversion (FPSPC) system will be performed. Comparison of results with previous studies of other systems, particularly Brayton and Thermionic, are made.

Schmitz, P.D. [Sverdrup Technology, Inc., Brook Park, OH (United States). Lewis Research Center Group; Mason, L.S. [National Aeronautics and Space Administration, Cleveland, OH (United States). Lewis Research Center

1994-09-01T23:59:59.000Z

245

Efficiency of carbon nanotubes water based nanofluids as coolants Salma Halelfadl a  

E-Print Network [OSTI]

previously determined. This may be helpful for using these nanofluids in real cooling systems. Keywords: Heat heating or cooling systems is used. Thus, there is a need to achieve compact systems, energy saving1 Efficiency of carbon nanotubes water based nanofluids as coolants Salma Halelfadl a , Thierry

Paris-Sud XI, Université de

246

Homogeneous fast-flux isotope-production reactor  

DOE Patents [OSTI]

A method is described for producing tritium in a liquid metal fast breeder reactor. Lithium target material is dissolved in the liquid metal coolant in order to facilitate the production and removal of tritium.

Cawley, W.E.; Omberg, R.P.

1982-08-19T23:59:59.000Z

247

Physics characteristics of a large, passive, pressure tube light water reactor with voided calandria  

SciTech Connect (OSTI)

A light water cooled and moderated pressure tube reactor concept has been developed that can survive loss-of-coolant accidents (LOCAs) without scram and without replenishing primary coolant inventory, while maintaining safe temperature limits on the fuel and pressure tube. The reactor employs a solid SiC-coated graphite fuel matrix in the pressure tubes and a calandria tank containing a low-pressure gas, surrounded by a graphite reflector. This normally voided calandria is connected to a light water heat sink. The cover gas displaces light water from the calandria during normal operation, while during LOCAs it allows passive calandria flooding. It is shown that such a system, with high void fraction in the core region, exhibits a high degree of neutron thermalization and a large prompt neutron lifetime, similar to D{sub 2}O moderated cores, although light water is used as both coolant and moderator. Moreover, the extremely large neutron migration length results in a strongly coupled core with a flat thermal flux profile and inherent stability against xenon spatial oscillations. The heterogeneous arrangement of the fuel and moderator ensures a negative void coefficient under all circumstances. Flooding of the calandria space with light water results in redundant reactor shutdown. Use of particle fuel allows attainment of high burnups.

Hejzlar, P.; Driscoll, M.J.; Todreas, N.E. [Massachusetts Inst. of Technology, Cambridge, MA (United States). Dept. of Nuclear Engineering

1995-11-01T23:59:59.000Z

248

Heat pipe cooled reactors for multi-kilowatt space power supplies  

SciTech Connect (OSTI)

Three nuclear reactor space power system designs are described that demonstrate how the use of high temperature heat pipes for reactor heat transport, combined with direct conversion of heat to electricity, can result in eliminating pumped heat transport loops for both primary reactor cooling and heat rejection. The result is a significant reduction in system complexity that leads to very low mass systems with high reliability, especially in the power range of 1 to 20 kWe. In addition to removing heat exchangers, electromagnetic pumps, and coolant expansion chambers, the heat pipe/direct conversion combination provides such capabilities as startup from the frozen state, automatic rejection of reactor decay heat in the event of emergency or accidental reactor shutdown, and the elimination of single point failures in the reactor cooling system. The power system designs described include a thermoelectric system that can produce 1 to 2 kWe, a bimodal modification of this system to increase its power level to 5 kWe and incorporate high temperature hydrogen propulsion capability, and a moderated thermionic reactor concept with 5 to 20 kWe power output that is based on beryllium modules that thermally couple cylindrical thermionic fuel elements (TFEs) to radiator heat pipes.

Ranken, W.A.; Houts, M.G.

1995-01-01T23:59:59.000Z

249

Rapid electrochemical screening of engine coolants. Correlation of electrochemical potentiometric measurements with ASTM D 1384 glassware corrosion test  

SciTech Connect (OSTI)

Engine coolants are typically subjected to comprehensive performance evaluations that involve multiple laboratory and field tests. These tests can take several weeks to conduct and can be expensive. The tests can involve everything from preliminary chemical screening to long term fleet tests. An important test conducted at the beginning of coolant formula development to screen the corrosion performance of engine coolants is described in ASTM D 1384. If the coolant formula passes the test, it is then subjected to more rigorous testing. Conducting the test described in ASTM D 1384 takes two weeks, and determining the coolant corrosion performance under several test parameters can takes resources and time that users seldom have. Therefore, it is very desirable to have tests that can be used for rapid screening and quality assurance of coolants. The purpose of this study was to conduct electrochemical tests that can ultimately be used for quick initial screening of engine coolants. The specific intent of the electrochemical tests is to use ASTM D 1384 as a model and to attempt to duplicate its results. Implementation of the electrochemical tests could accelerate the process of selecting promising coolant formulas and reduce coolant evaluation time and cost. Various electrochemical tests were conducted to determine the corrosion performance of several engine coolant formulas. The test results were compared to those obtained from the ASTM D 1384 test. These tests were conducted on the same metal specimens and under similar conditions as those used in the ASTM D 1384 test. The electrochemical tests included the determination of open circuit potential (OCP) for the various metal specimens, anodic and cathodic polarization curves for the various metal specimens, corrosion rate for metal specimens involved in a galvanic triad, and critical pitting potential (CPP) for aluminum (pitting of aluminum engine components and cooling systems is a cause for concern). The details for the methods and the correlation of the results to ASTM D 1384 tests results will be presented.

Doucet, G.P. [Shell Chemical Co., Houston, TX (United States); Jackson, J.M.; Kriegel, O.A.; Passwater, D.K. [Shell Oil Products Co., Houston, TX (United States); Prieto, N.E. [Petroferm Inc., Fernandina Beach, FL (United States)

1999-08-01T23:59:59.000Z

250

Nonlinear dynamical systems with data and model uncertainties subjected to seismic loads  

E-Print Network [OSTI]

Nonlinear dynamical systems with data and model uncertainties subjected to seismic loads Christophe loads with data uncertainties for the nonlinearities. An application to a multisupported reactor coolant and Acoustics Dpt., 92141, Clamart cedex, France ABSTRACT This paper deals with data uncertainties

Paris-Sud XI, Université de

251

Preventing fuel failure for a beyond design basis accident in a fluoride salt cooled high temperature reactor  

E-Print Network [OSTI]

The fluoride salt-cooled high-temperature reactor (FHR) combines high-temperature coated-particle fuel with a high-temperature salt coolant for a reactor with unique market and safety characteristics. This combination can ...

Minck, Matthew J. (Matthew Joseph)

2013-01-01T23:59:59.000Z

252

Neural net controlled tag gas sampling system for nuclear reactors  

DOE Patents [OSTI]

A method and system for providing a tag gas identifier to a nuclear fuel rod and analyze escaped tag gas to identify a particular failed nuclear fuel rod. The method and system include disposing a unique tag gas composition into a plenum of a nuclear fuel rod, monitoring gamma ray activity, analyzing gamma ray signals to assess whether a nuclear fuel rod has failed and is emitting tag gas, activating a tag gas sampling and analysis system upon sensing tag gas emission from a failed nuclear rod and evaluating the escaped tag gas to identify the particular failed nuclear fuel rod.

Gross, Kenneth C. (Bolingbrook, IL); Laug, Matthew T. (Idaho Fall, ID); Lambert, John D. B. (Wheaton, IL); Herzog, James P. (Downers Grove, IL)

1997-01-01T23:59:59.000Z

253

High Flux Isotope Reactor power upgrade status  

SciTech Connect (OSTI)

A return to 100-MW operation is being planned for the High Flux Isotope Reactor (HFIR). Recent improvements in fuel element manufacturing procedures and inspection equipment will be exploited to reduce hot spot and hot streak factors sufficiently to permit the power upgrade without an increase in primary coolant pressure. Fresh fuel elements already fabricated for future use are being evaluated individually for power upgrade potential based on their measured coolant channel dimensions.

Rothrock, R.B.; Hale, R.E. [Oak Ridge National Lab., TN (United States); Cheverton, R.D. [Delta-21 Resources Inc., Oak Ridge, TN (United States)

1997-03-01T23:59:59.000Z

254

Reliability assessment of Passive Containment Cooling System of an Advanced Reactor using APSRA methodology  

Science Journals Connector (OSTI)

Abstract Passive Systems are increasingly playing a prominent role in the advanced nuclear reactor systems and are being utilised in normal operations as well as safety systems of the reactors following an accident. The Passive Containment Cooling System (PCCS) is one of the several passive safety features in an Advanced Reactor (AHWR). In this paper, the APSRA methodology has been employed for reliability evaluation of the PCCS of AHWR. Performance assessment of the PCCS is initially performed during a postulated design basis LOCA using the best-estimate code RELAP5/Mod 3.2. The parameters affecting the system performance are then identified and considered for further analysis. Based on some pre-determined failure criterion, the failure surface for the system is predicted using the best-estimate code taking into account the deviations of the identified parameters from their nominal states as well as the model uncertainties inherent to the best estimate code. Root diagnosis is then carried out to determine the various failure causes, which occurs mainly due to malfunctioning of mechanical components. The failure probabilities of the various components are assessed through a classical PSA treatment using generic data. The reliability of the PCCS is then evaluated from the probability of availability of these components.

Mukesh Kumar; Aranyak Chakravarty; A.K. Nayak; Hari Prasad; V. Gopika

2014-01-01T23:59:59.000Z

255

ADORE: Alternative detector layout optimization for ROP system of CANDU reactors  

Science Journals Connector (OSTI)

In CANDU® reactor design, the regional overpower protection (ROP) systems protect the reactor against overpower in the fuel which could reduce the safety margin-to-dryout. Specifically for the CANDU® 600 MW (CANDU 6) design, there are two ROP systems in the core, one for each fast-acting shutdown systems. Each ROP system includes a number of fast-responding, self-powered flux detectors suitably distributed throughout the core within vertical and horizontal assemblies. The placement of these ROP detectors is a challenging discrete optimization problem. The DLO (detector layout optimization) module of ROVER-F code was used to design the existing ROP detector layout of CANDU 6 reactors. In the past couple of years, a new methodology for designing the detector layout for the ROP system, called DETPLASA algorithm, has been developed. This method utilizes the simulated annealing (SA) technique to optimize the placement of the detectors in the core. This algorithm was developed to overcome the shortcoming of DLO method to produce a detector layout configuration when the size of the problem is large. An alternative method has been recently developed for solving the ROP detector placement problem. This method is called ADORE (Alternative Detector layout Optimization for \\{REgional\\} overpower protection system). Although technically any stochastic optimization technique can be utilized, presently this method utilizes the SA technique as its optimization engine. This paper presents an overview of ADORE methodology and provides some numerical results from its execution.

Doddy Y.F. Kastanya

2011-01-01T23:59:59.000Z

256

Combined on-board hydride slurry storage and reactor system and process for hydrogen-powered vehicles and devices  

SciTech Connect (OSTI)

An on-board hydride storage system and process are described. The system includes a slurry storage system that includes a slurry reactor and a variable concentration slurry. In one preferred configuration, the storage system stores a slurry containing a hydride storage material in a carrier fluid at a first concentration of hydride solids. The slurry reactor receives the slurry containing a second concentration of the hydride storage material and releases hydrogen as a fuel to hydrogen-power devices and vehicles.

Brooks, Kriston P; Holladay, Jamelyn D; Simmons, Kevin L; Herling, Darrell R

2014-11-18T23:59:59.000Z

257

Evaluation of engine coolant recycling processes: Part 2  

SciTech Connect (OSTI)

Engine coolant recycling continues to provide solutions to both economic and environmental challenges often faced with the disposal of used engine coolant. General Motors` Service Technology Group (STG), in a continuing effort to validate the general practice of recycling engine coolants, has conducted an in-depth study on the capabilities of recycled coolants. Various recycling processes ranging from complex forms of fractional distillation to simple filtration were evaluated in this study to best represent the current state of coolant recycling technology. This study incorporates both lab and (limited) fleet testing to determine the performance capabilities of the recycled coolants tested. While the results suggest the need for additional studies in this area, they reveal the true capabilities of all types of engine coolant recycling technologies.

Bradley, W.H. [General Motors, Warren, MI (United States). Service Technology Group

1999-08-01T23:59:59.000Z

258

Gaseous fission product management for molten salt reactors and vented fuel systems  

SciTech Connect (OSTI)

Fission gas disposal is one of the unresolved difficulties for Molten Salt Reactors (MSRs) and advanced reactors with vented fuel systems. As these systems operate, they produce many radioactive isotopes of xenon and krypton (e.g. {sup 135}Xe t{sub 1/2} = 9.14 hours and {sup 85}Kr t{sub 1/2}= 10.73 years). Removing these gases proves vital to the success of such reactor designs for two reasons. First, the gases act as large neutron sinks which decrease reactivity and must be counterbalanced by increasing fuel loading. Second, for MSRs, inert fission product gases naturally separate quickly from high temperature salts, thus creating high vapor pressure which poses safety concerns. For advanced reactors with solid vented fuel, the gases are allowed to escape into an off-gas system and thus must be managed. Because of time delays in transport of fission product gases in vented fuel systems, some of the shorter-lived radionuclides will decay away thereby reducing the fission gas source term relative to an MSR. To calculate the fission gas source term of a typical molten salt reactor, we modeled a 1000 MWe graphite moderated thorium MSR similar to that detailed in Mathieu et al. [1]. The fuel salt used in these calculations was LiF (78 mole percent) - (HN)F 4 (22 mole percent) with a heavy nuclide composition of 3.86% {sup 233}U and 96.14% {sup 232}Th by mass. Before we can remove the fission product gases produced by this reactor configuration, we must first develop an appropriate storage mechanism. The gases could be stored in pressurized containers but then one must be concerned about bottle failure. Methods to trap noble gases in matrices are expensive and complex. Alternatively, there are direct storage/disposal options: direct injection into the Earth or injecting a grout-based product into the Earth. Advances in drilling technologies, hydro fracture technologies, and methods for the sequestration of carbon dioxide from fossil fuel plants are creating new options for disposal of fission gas wastes. In each option, lithostatic pressure, a kilometer or more underground, eliminates the pressure driving force for noble gas release and dissolves any untrapped gas in deep groundwater or into incorporated solid waste forms. The options, challenges, and potential for these methods to dispose of gaseous fission products are described. With this research, we hope to help both MSRs and other advanced reactors come one step closer to commercialization. (authors)

Messenger, S. J. [Massachusetts Inst. of Technology, 77 Massachusetts Ave., 54-1717, Cambridge, MA 02139 (United States); Forsberg, C. [Massachusetts Inst. of Technology, 77 Massachusetts Ave., 24-207, Cambridge, MA 02139 (United States); Massie, M. [Massachusetts Inst. of Technology, 77 Massachusetts Ave., NW12-230, Cambridge, MA 02139 (United States)

2012-07-01T23:59:59.000Z

259

Multi-unit Operations in Non-Nuclear Systems: Lessons Learned for Small Modular Reactors  

SciTech Connect (OSTI)

The nuclear-power community has reached the stage of proposing advanced reactor designs to support power generation for decades to come. Small modular reactors (SMRs) are one approach to meet these energy needs. While the power output of individual reactor modules is relatively small, they can be grouped to produce reactor sites with different outputs. Also, they can be designed to generate hydrogen, or to process heat. Many characteristics of SMRs are quite different from those of current plants and may be operated quite differently. One difference is that multiple units may be operated by a single crew (or a single operator) from one control room. The U.S. Nuclear Regulatory Commission (NRC) is examining the human factors engineering (HFE) aspects of SMRs to support licensing reviews. While we reviewed information on SMR designs to obtain information, the designs are not completed and all of the design and operational information is not yet available. Nor is there information on multi-unit operations as envisioned for SMRs available in operating experience. Thus, to gain a better understanding of multi-unit operations we sought the lesson learned from non-nuclear systems that have experience in multi-unit operations, specifically refineries, unmanned aerial vehicles and tele-intensive care units. In this paper we report the lessons learned from these systems and the implications for SMRs.

OHara J. M.; Higgins, J.; DAgostino, A.

2012-01-17T23:59:59.000Z

260

Neutron economic reactivity control system for light water reactors  

DOE Patents [OSTI]

A neutron reactivity control system for a LWBR incorporating a stationary seed-blanket core arrangement. The core arrangement includes a plurality of contiguous hexagonal shaped regions. Each region has a central and a peripheral blanket area juxapositioned an annular seed area. The blanket areas contain thoria fuel rods while the annular seed area includes seed fuel rods and movable thoria shim control rods.

Luce, Robert G. (Glenville, NY); McCoy, Daniel F. (Latham, NY); Merriman, Floyd C. (Rotterdam, NY); Gregurech, Steve (Scotia, NY)

1989-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

High Temperature Gas-Cooled Reactor Program. Modular HTGR systems design and cost summary. [Methane reforming; steam cycle-cogeneration  

SciTech Connect (OSTI)

This report provides a summary description of the preconceptual design and energy product costs of the modular High Temperature Gas-Cooled Reactor (HTGR). The reactor system was studied for two applications: (1) reforming of methane to produce synthesis gas and (2) steam cycle/cogeneration to produce process steam and electricity.

Not Available

1983-09-01T23:59:59.000Z

262

Review of the proposed materials of construction for the SBWR and AP600 advanced reactors  

SciTech Connect (OSTI)

Two advanced light water reactor (LWR) concepts, namely the General Electric Simplified Boiling Water Reactor (SBWR) and the Westinghouse Advanced Passive 600 MWe Reactor (AP600), were reviewed in detail by Argonne National Laboratory. The objectives of these reviews were to (a) evaluate proposed advanced-reactor designs and the materials of construction for the safety systems, (b) identify all aging and environmentally related degradation mechanisms for the materials of construction, and (c) evaluate from the safety viewpoint the suitability of the proposed materials for the design application. Safety-related systems selected for review for these two LWRs included (a) reactor pressure vessel, (b) control rod drive system and reactor internals, (c) coolant pressure boundary, (d) engineered safety systems, (e) steam generators (AP600 only), (f) turbines, and (g) fuel storage and handling system. In addition, the use of cobalt-based alloys in these plants was reviewed. The selected materials for both reactors were generally sound, and no major selection errors were found. It was apparent that considerable thought had been given to the materials selection process, making use of lessons learned from previous LWR experience. The review resulted in the suggestion of alternate an possibly better materials choices in a number of cases, and several potential problem areas have been cited.

Diercks, D.R.; Shack, W.J.; Chung, H.M.; Kassner, T.F. [Argonne National Lab., IL (United States)

1994-06-01T23:59:59.000Z

263

Lead Coolant Test Facility Technical and Functional Requirements, Conceptual Design, Cost and Construction Schedule  

SciTech Connect (OSTI)

This report presents preliminary technical and functional requirements (T&FR), thermal hydraulic design and cost estimate for a lead coolant test facility. The purpose of this small scale facility is to simulate lead coolant fast reactor (LFR) coolant flow in an open lattice geometry core using seven electrical rods and liquid lead or lead-bismuth eutectic. Based on review of current world lead or lead-bismuth test facilities and research need listed in the Generation IV Roadmap, five broad areas of requirements of basis are identified: Develop and Demonstrate Prototype Lead/Lead-Bismuth Liquid Metal Flow Loop Develop and Demonstrate Feasibility of Submerged Heat Exchanger Develop and Demonstrate Open-lattice Flow in Electrically Heated Core Develop and Demonstrate Chemistry Control Demonstrate Safe Operation and Provision for Future Testing. These five broad areas are divided into twenty-one (21) specific requirements ranging from coolant temperature to design lifetime. An overview of project engineering requirements, design requirements, QA and environmental requirements are also presented. The purpose of this T&FRs is to focus the lead fast reactor community domestically on the requirements for the next unique state of the art test facility. The facility thermal hydraulic design is based on the maximum simulated core power using seven electrical heater rods of 420 kW; average linear heat generation rate of 300 W/cm. The core inlet temperature for liquid lead or Pb/Bi eutectic is 420oC. The design includes approximately seventy-five data measurements such as pressure, temperature, and flow rates. The preliminary estimated cost of construction of the facility is $3.7M. It is also estimated that the facility will require two years to be constructed and ready for operation.

Soli T. Khericha

2006-09-01T23:59:59.000Z

264

An on-line regional overpower surveillance system for Candu reactors  

SciTech Connect (OSTI)

The current methodology for establishing Regional Overpower Protection (ROP) trip set-points for Canada Deuterium Uranium (Candu{sup R} reactors requires an extensive and detailed assessment of the plant based on a distribution of channel and bundle powers (flux shapes) calculated from a range of device configurations (e.g., zone controller levels, adjuster bank movements, mechanical control absorber movements, shut-off rod insertions) and a set of thermalhydraulic plant data (channel flows, reactor inlet-header temperatures, channel differential pressure). An on-line approach would provide an interface to assist operators in routine monitoring, diagnostic and maintenance activities by providing Critical Channel Powers (CCP) and ROP set points from instantaneous flux shapes derived from real-time detector readings and associated thermalhydraulic conditions. This paper describes an Advanced On-Line Regional Overpower Surveillance (AOL-ROS) system currently under development at Atomic Energy of Canada Limited (AECL) for Candu reactors. Development has been based on an assessment using instantaneous operating data for the period February to April 2004 from a Candu 6 reactor located at Point Lepreau, New Brunswick (Canada). (authors)

Wallace, D. J.; Caxaj, V.; Seidu, A. S.; Hartmann, W.; Sur, B.; McDonald, A. [Atomic Energy of Canada Limited, 2251 Speakman Dr., Mississauga, Ont. L5K 1B2 (Canada)

2006-07-01T23:59:59.000Z

265

Advanced Gas-Cooled Nuclear Reactor Materials Evaluation and Development Program. Progress report, July 1, 1979-September 30, 1979  

SciTech Connect (OSTI)

The results of work performed from July 1, 1979 through September 30, 1979 on the Advanced Gas-Cooled Nuclear Reactor Materials Evaluation and Development Program are presented. The objectives of this program are to evaluate candidate alloys for Very High Temperature Reactor (VHTR) Nuclear Process Heat (NPH) and Direct Cycle Helium Turbine (DCHT) applications, in terms of the effect of simulated reactor primary coolant (helium containing small amounts of various other gases), high temperatures, and long time exposures, on the mechanical properties and structural and surface stability of selected candidate alloys. A second objective is to select and recommend materials for future test facilities and more extensive qualification programs. Work covered in this report includes the activities associated with the status of the simulated reactor helium supply system, testing equipment, and gas chemistry analysis instrumentation and equipment. The status of the data management system is presented. In addition, the progress in the screening test program is described.

Not Available

1980-03-07T23:59:59.000Z

266

Advanced Fusion Reactors for Space Propulsion and Power Systems  

SciTech Connect (OSTI)

In recent years the methodology proposed for conversion of light elements into energy via fusion has made steady progress. Scientific studies and engineering efforts in advanced fusion systems designs have introduced some new concepts with unique aspects including consideration of Aneutronic fuels. The plant parameters for harnessing aneutronic fusion appear more exigent than those required for the conventional fusion fuel cycle. However aneutronic fusion propulsion plants for Space deployment will ultimately offer the possibility of enhanced performance from nuclear gain as compared to existing ionic engines as well as providing a clean solution to Planetary Protection considerations and requirements. Proton triggered 11Boron fuel (p- 11B) will produce abundant ion kinetic energy for In-Space vectored thrust. Thus energetic alpha particles' exhaust momentum can be used directly to produce high Isp thrust and also offer possibility of power conversion into electricity. p-11B is an advanced fusion plant fuel with well understood reaction kinematics but will require some new conceptual thinking as to the most effective implementation.

Chapman, John J.

2011-06-15T23:59:59.000Z

267

Advanced Reactors Thermal Energy Transport for Process Industries  

SciTech Connect (OSTI)

The operation temperature of advanced nuclear reactors is generally higher than commercial light water reactors and thermal energy from advanced nuclear reactor can be used for various purposes such as liquid fuel production, district heating, desalination, hydrogen production, and other process heat applications, etc. Some of the major technology challenges that must be overcome before the advanced reactors could be licensed on the reactor side are qualification of next generation of nuclear fuel, materials that can withstand higher temperature, improvement in power cycle thermal efficiency by going to combined cycles, SCO2 cycles, successful demonstration of advanced compact heat exchangers in the prototypical conditions, and from the process side application the challenge is to transport the thermal energy from the reactor to the process plant with maximum efficiency (i.e., with minimum temperature drop). The main focus of this study is on doing a parametric study of efficient heat transport system, with different coolants (mainly, water, He, and molten salts) to determine maximum possible distance that can be achieved.

P. Sabharwall; S.J. Yoon; M.G. McKellar; C. Stoots; George Griffith

2014-07-01T23:59:59.000Z

268

Reliability analysis of safety grade decay heat removal system of Indian prototype fast breeder reactor  

Science Journals Connector (OSTI)

The 500 MW Indian pool type Prototype Fast Breeder Reactor (PFBR), is provided with two independent and diverse Decay Heat Removal (DHR) systems viz., Operating Grade Decay Heat Removal System (OGDHRS) and Safety Grade Decay Heat Removal System (SGDHRS). OGDHRS utilizes the secondary sodium loops and Steam–Water System with special decay heat removal condensers for DHR function. The unreliability of this system is of the order of 0.1–0.01. The safety requirements of the present generation of fast reactors are very high, and specifically for DHR function the failure frequency should be less than ?1E-7/ry. Therefore, a passive SGDHR system using four completely independent thermo-siphon loops in natural convection mode is provided to ensure adequate core cooling for all Design Basis Events. The very high reliability requirement for DHR function is achieved mainly with the help of SGDHRS. This paper presents the reliability analysis of SGDHR system. Analysis is performed by Fault Tree method using ‘CRAFT’ software developed at Indira Gandhi Centre for Atomic Research. This software has special features for compact representation and CCF analysis of high redundancy safety systems encountered in nuclear reactors. Common Cause Failures (CCF) are evaluated by ? factor method. The reliability target for SGDHRS arrived from DHR reliability requirement and the ultimate number of demands per year (7/y) on SGDHRS is that the failure frequency should be ?1.4E-8/de. Since it is found from the analysis that the unreliability of SGDHRS with identical loops is 5.2E-6/de and dominated by leak rates of components like AHX, DHX and sodium dump and isolation valves, options with diversity measures in important components were studied. The failure probability of SGDHRS for a design consisting of 2 types of diverse loops (Diverse AHX, DHX and sodium dump and isolation valves) is 2.1E-8/de, which practically meets the reliability requirement.

A. John Arul; C. Senthil Kumar; S. Athmalingam; Om Pal Singh; K. Suryaprakasa Rao

2006-01-01T23:59:59.000Z

269

Numerical Study on Crossflow Printed Circuit Heat Exchanger for Advanced Small Modular Reactors  

SciTech Connect (OSTI)

Various fluids such as water, gases (helium), molten salts (FLiNaK, FLiBe) and liquid metal (sodium) are used as a coolant of advanced small modular reactors (SMRs). The printed circuit heat exchanger (PCHE) has been adopted as the intermediate and/or secondary heat exchanger of SMR systems because this heat exchanger is compact and effective. The size and cost of PCHE can be changed by the coolant type of each SMR. In this study, the crossflow PCHE analysis code for advanced small modular reactor has been developed for the thermal design and cost estimation of the heat exchanger. The analytical solution of single pass, both unmixed fluids crossflow heat exchanger model was employed to calculate a two dimensional temperature profile of a crossflow PCHE. The analytical solution of crossflow heat exchanger was simply implemented by using built in function of the MATLAB program. The effect of fluid property uncertainty on the calculation results was evaluated. In addition, the effect of heat transfer correlations on the calculated temperature profile was analyzed by taking into account possible combinations of primary and secondary coolants in the SMR systems. Size and cost of heat exchanger were evaluated for the given temperature requirement of each SMR.

Su-Jong Yoon [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Piyush Sabharwall [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Eung-Soo Kim [Seoul National Univ., Seoul (Korea, Republic of)

2014-03-01T23:59:59.000Z

270

Consequence evaluation of radiation embrittlement of Trojan reactor pressure vessel supports  

SciTech Connect (OSTI)

This report describes a consequence evaluation to address safety concerns raised by the radiation embrittlement of the reactor pressure vessel (RPV) supports for the Trojan nuclear power plant. The study comprises a structural evaluation and an effects evaluation and assumes that all four reactor vessel supports have completely lost the load carrying capability. By demonstrating that the ASME code requirements governing Level D service limits are satisfied, the structural evaluation concludes that the Trojan reactor coolant loop (RCL) piping is capable of transferring loads to the steam generator (SG) supports and the reactor coolant pump (RCP) supports. A subsequent design margins to accommodate additional loads transferred to them through the RCL piping. The effects evaluation, employing a systems analysis approach, investigates initiating events and the reliability of the engineered safeguard systems as the RPV is subject to movements caused by the RPV support failure. The evaluation identifies a number of areas of additional safety concerns, but further investigation of the above safety concerns, however, concludes that a hypothetical failure of the Trojan RPV supports due to radiation embrittlement will not result in consequences of significant safety concerns.

Lu, S.C.; Sommer, S.C.; Johnson, G.L. (Lawrence Livermore National Lab., CA (USA)); Lambert, H.E. (FTA Associates, Oakland, CA (USA))

1990-10-01T23:59:59.000Z

271

Bellows-Type Accumulators for Liquid Metal Loops of Space Reactor Power Systems  

SciTech Connect (OSTI)

In many space nuclear power systems, the primary and/or secondary loops use liquid metal working fluids, and require accumulators to accommodate the change in the liquid metal volume and maintain sufficient subcooling to avoid boiling. This paper developed redundant and light-weight bellows-type accumulators with and without a mechanical spring, and compared the operating condition and mass of the accumulators for different types of liquid metal working fluids and operating temperatures: potassium, NaK-78, sodium and lithium loops of a total capacity of 50 liters and nominal operating temperatures of 840 K, 860 K, 950 K and 1340 K, respectively. The effects of using a mechanical spring and different structural materials on the design, operation and mass of the accumulators are also investigated. The structure materials considered include SS-316, Hastelloy-X, C-103 and Mo-14Re. The accumulator without a mechanical spring weighs 23 kg and 40 kg for a coolant subcooling of 50 K and 100 K, respectively, following a loss of the fill gas. The addition of a mechanical spring comes with a mass penalty, in favor of higher redundancy and maintaining a higher liquid metal subcooling.

Tournier, Jean-Michel; El-Genk, Mohamed S. [Institute for Space and Nuclear Power Studies, University of New Mexico, Albuquerque, NM 87131 (United States); Chemical and Nuclear Engineering Department, University of New Mexico, Albuquerque, NM 87131 (United States)

2006-01-20T23:59:59.000Z

272

The results of systems tests of the 500 kV busbar controllable shunting reactor in the Tavricheskaya substation  

Science Journals Connector (OSTI)

The results of systems tests of the 500 kV busbar magnetization-controllable shunting reactor (CSR), set up in the Tavricheskaya substation, including measurements of the quality of the...

S. I. Gusev; V. N. Karpov; A. N. Kiselev; V. I. Kochkin

2009-09-01T23:59:59.000Z

273

Reliability analysis of a passive cooling system using a response surface with an application to the Flexible Conversion Ratio Reactor  

E-Print Network [OSTI]

A comprehensive risk-informed methodology for passive safety system design and performance assessment is presented and demonstrated on the Flexible Conversion Ratio Reactor (FCRR). First, the methodology provides a framework ...

Fong, Christopher J. (Christopher Joseph)

2008-01-01T23:59:59.000Z

274

Flibe Use in Fusion Reactors - An Initial Safety Assessment  

SciTech Connect (OSTI)

This report is an initial effort to identify and evaluate safety issues associated with the use of Flibe (LiF-BeF2) as a molten salt coolant for nuclear fusion power plant applications. Flibe experience in the Molten Salt Reactor Experiment is briefly reviewed. Safety issues identified include chemical toxicity, radiological issues resulting from neutron activation, and the operational concerns of handling a high temperature coolant. Beryllium compounds and fluorine pose be toxicological concerns. Some controls to protect workers are discussed. Since Flibe has been handled safely in other applications, its hazards appear to be manageable. Some safety issues that require further study are pointed out. Flibe salt interaction with strong magnetic fields should be investigated. Evolution of Flibe constituents and activation products at high temperature (i.e., will Fluorine release as a gas or remain in the molten salt) is an issue. Aerosol and tritium release from a Flibe spill requires study, as does neutronics analysis to characterize radiological doses. Tritium migration from Flibe into the cooling system is also a safety concern. Investigation of these issues will help determine the extent to which Flibe shows promise as a fusion power plant coolant or plasma-facing material.

Cadwallader, Lee Charles; Longhurst, Glen Reed

1999-04-01T23:59:59.000Z

275

Radiation safety assessment of a system of small reactors for distributed energy  

Science Journals Connector (OSTI)

......of safety or reliability. On the other...said that marine reactors are appropriate...300 MW thermal reactor power was used. The analysis for the normal...9 108 Sv h1. Analysis of effective...immediately after reactor shutdown was......

N. Odano; T. Ishida

2005-12-20T23:59:59.000Z

276

Conceptual design of the bimodal nuclear power system based on the ‘‘Romashka’’ type reactor with thermionic energy conversion system  

Science Journals Connector (OSTI)

The paper presents conceptual design of the bimodal space nuclear power system (NPS) based on the high?temperature reactor of ROMASHKA type with thermoninic energy conversion system. At the heart of the design is an employment of close?spaced thermionic diodes operating in a quasi?vacuum mode. The paper gives preliminary estimates of the NPS neutron?physical electric thermophysical and mass?dimensional parameters for the reactor electric power of 25 kW and propulsive thrust of about 80 N. Discussed are peculiarities of the combined mode wherein electric power is generated along with propulsive thrust. The paper contains results of the design studies performed by the Small Business ‘‘NP Energotech’’ under the Agreement with Rockwell International/Rocketdyne Division and according to the Rocketdyne Division provided Design Requirements. Involved in the work was the team of specialists of RRC ‘‘Kurchatov Institute’’ ‘‘Red Star’’ State Enterprise and Research Institute of SPA ‘‘Luch’’

Nikolai N. Ponmarev?Stepnoi; Veniamin A. Usov; Yuri V. Nikolaev; Stanislav A. Yeriemin; Yevgeny Ye. Zhabotinski; Anatoly Ya. Galkin; Yevgeny D. Avdoshyn

1995-01-01T23:59:59.000Z

277

PACCAR CRADA: Experimental Investigation in Coolant Boiling in...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

of Power Electronics of Electric Vehicles with Small Channel Coolant Boiling Cooling Boiling in Head Region - PACCAR Integrated Underhood Thermal and External Aerodynamics- Cummins...

278

Dynamic Modeling and Control of Nuclear Reactors Coupled to Closed-Loop Brayton Cycle Systems using SIMULINK{sup TM}  

SciTech Connect (OSTI)

The operation of space reactors for both in-space and planetary operations will require unprecedented levels of autonomy and control. Development of these autonomous control systems will require dynamic system models, effective control methodologies, and autonomous control logic. This paper briefly describes the results of reactor, power-conversion, and control models that are implemented in SIMULINK{sup TM} (Simulink, 2004). SIMULINK{sup TM} is a development environment packaged with MatLab{sup TM} (MatLab, 2004) that allows the creation of dynamic state flow models. Simulation modules for liquid metal, gas cooled reactors, and electrically heated systems have been developed, as have modules for dynamic power-conversion components such as, ducting, heat exchangers, turbines, compressors, permanent magnet alternators, and load resistors. Various control modules for the reactor and the power-conversion shaft speed have also been developed and simulated. The modules are compiled into libraries and can be easily connected in different ways to explore the operational space of a number of potential reactor, power-conversion system configurations, and control approaches. The modularity and variability of these SIMULINK{sup TM} models provides a way to simulate a variety of complete power generation systems. To date, both Liquid Metal Reactors (LMR), Gas Cooled Reactors (GCR), and electric heaters that are coupled to gas-dynamics systems and thermoelectric systems have been simulated and are used to understand the behavior of these systems. Current efforts are focused on improving the fidelity of the existing SIMULINK{sup TM} modules, extending them to include isotopic heaters, heat pipes, Stirling engines, and on developing state flow logic to provide intelligent autonomy. The simulation code is called RPC-SIM (Reactor Power and Control-Simulator)

Wright, Steven A.; Sanchez, Travis [Sandia National Laboratories, Org 6872 MS-1146, PO Box 5800 Albuquerque, New Mexico 87185 (United States)

2005-02-06T23:59:59.000Z

279

Performance characteristics of the annular core research reactor fuel motion detection system  

SciTech Connect (OSTI)

Recent proof tests have shown that the annular core research reactor (ACRR) fuel motion detection system has reached its design goals of providing high temporal and spatial resolution pictures of fuel distributions in the ACRR. The coded aperture imaging system (CAIS) images the fuel by monitoring the fission gamma rays from the fuel that pass through collimators in the reactor core. The gamma-ray beam is modulated by coded apertures before producing a visible light coded image in thin scintillators. Each coded image is then amplified and recorded by an opticalimage-intensifier/fast-framing-camera combination. The proximity to the core and the coded aperture technique provide a high data collection rate and high resolution. Experiments of CAIS at the ACRR conducted under steady-state operation have documented the beneficial effects of changes in the radiation shielding and imaging technique. The spatial resolutions are 1.7 mm perpendicular to the axis of a single liquid-metal fast breeder reactor fuel pin and 9 mm in the axial dimension. Changes in mass of 100 mg in each resolution element can be detected each frame period, which may be from 5 to 100 ms. This diagnostic instrument may help resolve important questions in fuel motion phenomenology.

Kelly, J.G.; Stalker, K.T.

1983-12-01T23:59:59.000Z

280

Experimental Breeder Reactor-II Primary Tank System Wash Water Workshop  

Broader source: Energy.gov (indexed) [DOE]

Pre-Developmental Pre-Developmental INL EBR-II Wash Water Treatment Technologies (PBS # ADSHQTD0100 (0003199)) EBR-II Wash Water Workshop - The majority of the sodium has been removed, remaining material is mostly passivated. Similar closure projects have been successfully completed. Engineering needs to be developed to apply the OBA path. Page 1 of 2 Idaho National Laboratory Idaho Experimental Breeder Reactor-II Primary Tank System Wash Water Workshop Challenge In 1994 Congress ordered the shutdown of the Experimental Breeder Reactor-II (EBR-II) and a closure project was initiated. The facility was placed in cold shutdown, engineering began on sodium removal, the sodium was drained in 2001 and the residual sodium chemically passivated to render it less reactive in 2005. Since that time, approximately 700 kg of metallic sodium and 3500 kg of sodium bicarbonate remain in the facility. The

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Expert system for identification of simultaneous and sequential reactor fuel failures with gas tagging  

DOE Patents [OSTI]

Failure of a fuel element in a nuclear reactor core is determined by a gas tagging failure detection system and method. Failures are catalogued and characterized after the event so that samples of the reactor's cover gas are taken at regular intervals and analyzed by mass spectroscopy. Employing a first set of systematic heuristic rules which are applied in a transformed node space allows the number of node combinations which must be processed within a barycentric algorithm to be substantially reduced. A second set of heuristic rules treats the tag nodes of the most recent one or two leakers as "background" gases, further reducing the number of trial node combinations. Lastly, a "fuzzy" set theory formalism minimizes experimental uncertainties in the identification of the most likely volumes of tag gases. This approach allows for the identification of virtually any number of sequential leaks and up to five simultaneous gas leaks from fuel elements.

Gross, Kenny C. (Bolingbrook, IL)

1994-01-01T23:59:59.000Z

282

Expert system for identification of simultaneous and sequential reactor fuel failures with gas tagging  

DOE Patents [OSTI]

Failure of a fuel element in a nuclear reactor core is determined by a gas tagging failure detection system and method. Failures are catalogued and characterized after the event so that samples of the reactor's cover gas are taken at regular intervals and analyzed by mass spectroscopy. Employing a first set of systematic heuristic rules which are applied in a transformed node space allows the number of node combinations which must be processed within a barycentric algorithm to be substantially reduced. A second set of heuristic rules treats the tag nodes of the most recent one or two leakers as background'' gases, further reducing the number of trial node combinations. Lastly, a fuzzy'' set theory formalism minimizes experimental uncertainties in the identification of the most likely volumes of tag gases. This approach allows for the identification of virtually any number of sequential leaks and up to five simultaneous gas leaks from fuel elements. 14 figs.

Gross, K.C.

1994-07-26T23:59:59.000Z

283

Nuclear reactor fuel assembly duct-tube-to-inlet-nozzle attachment system  

DOE Patents [OSTI]

A reusable system for removably attaching the lower end 21 of a nuclear reactor fuel assembly duct tube to an upper end 11 of a nuclear reactor fuel assembly inlet nozzle. The duct tube's lower end 21 has sides terminating in locking tabs 22 which end in inwardly-extending flanges 23. The flanges 23 engage recesses 13 in the top section 12 of the inlet nozzle's upper end 11. A retaining collar 30 slides over the inlet nozzle's upper end 11 to restrain the flanges 23 in the recesses 13. A locking nut 40 has an inside threaded portion 41 which engages an outside threaded portion 15 of the inlet nozzle's upper end 11 to secure the retaining collar 30 against protrusions 24 on the duct tube's sides.

Christiansen, David W. (Kennewick, WA); Smith, Bob G. (Kennewick, WA)

1982-01-01T23:59:59.000Z

284

Design and optimization of the heat rejection system for a liquid cooled thermionic space nuclear reactor power system  

SciTech Connect (OSTI)

The heat transport subsystem for a liquid metal cooled thermionic space nuclear power system was modelled using algorithms developed in support of previous nuclear power system study programs, which date back to the SNAP-10A flight system. The model was used to define the optimum dimensions of the various components in the heat transport subsystem subjected to the constraints of minimizing mass and achieving a launchable package that did not require radiator deployment. The resulting design provides for the safe and reliable cooling of the nuclear reactor in a proven lightweight design.

Moriarty, M.P. (Rocketdyne Division, Rockwell International Corporation, 6633 Canoga Avenue, P.O. Box 7922, Canoga Park, California 91309-7922 (United States))

1993-01-15T23:59:59.000Z

285

Testing of Passive Safety System Performance for Higher Power Advanced Reactors  

SciTech Connect (OSTI)

This report describes the results of NERI research on the testing of advanced passive safety performance for the Westinghouse AP1000 design. The objectives of this research were: (a) to assess the AP1000 passive safety system core cooling performance under high decay power conditions for a spectrum of breaks located at a variety of locations, (b) to compare advanced thermal hydraulic computer code predictions to the APEX high decay power test data and (c) to develop new passive safety system concepts that could be used for Generation IV higher power reactors.

brian G. Woods; Jose Reyes, Jr.; John Woods; John Groome; Richard Wright

2004-12-31T23:59:59.000Z

286

Apparatus and systems for measuring elongation of objects, methods of measuring, and reactor  

DOE Patents [OSTI]

Elongation measurement apparatuses and systems comprise at least two Linear Variable Differential Transformers (LVDTs) with a push rod coupled to each of the at least two LVDTs at one longitudinal end thereof. At least one push rod extends to a base and is coupled thereto at an opposing longitudinal end, and at least one other push rod extends to a location spaced apart from the base and is configured to receive a sample between an opposing longitudinal end of the at least one other push rod and the base. Nuclear reactors comprising such apparatuses and systems and methods of measuring elongation of a material are also disclosed.

Rempe, Joy L. (Idaho Falls, ID); Knudson, Darrell L. (Firth, ID); Daw, Joshua E. (Idaho Falls, ID); Condie, Keith G. (Idaho Falls, ID); Stoots, Carl M. (Idaho Falls, ID)

2011-11-29T23:59:59.000Z

287

Fuel cycle facility control system for the Integral Fast Reactor Program  

SciTech Connect (OSTI)

As part of the Integral Fast Reactor (IFR) Fuel Demonstration, a new distributed control system designed, implemented and installed. The Fuel processes are a combination of chemical and machining processes operated remotely. To meet this special requirement, the new control system provides complete sequential logic control motion and positioning control and continuous PID loop control. Also, a centralized computer system provides near-real time nuclear material tracking, product quality control data archiving and a centralized reporting function. The control system was configured to use programmable logic controllers, small logic controllers, personal computers with touch screens, engineering work stations and interconnecting networks. By following a structured software development method the operator interface was standardized. The system has been installed and is presently being tested for operations.

Benedict, R.W.; Tate, D.A.

1993-09-01T23:59:59.000Z

288

Advanced Gas Cooled Nuclear Reactor Materials Evaluation and Development Program. Progress report, January 1, 1980-March 31, 1980  

SciTech Connect (OSTI)

Results are presented of work performed on the Advanced Gas-Cooled Nuclear Reactor Materials Evaluation and Development Program. The objectives of this program are to evaluate candidate alloys for Very High Temperature Reactor (VHTR) Nuclear Process Heat (NPH) and Direct Cycle Helium Turbine (DCHT) applications, in terms of the effect of simulated reactor primary coolant (helium containing small amounts of various other gases), high temperatures, and long time exposures, on the mechanical properties and structural and surface stability of selected candidate alloys. A second objective is to select and recommend materials for future test facilities and more extensive qualification programs. Included are the activities associated with the status of the simulated reactor helium supply system, testing equipment and gas chemistry analysis instrumentation and equipment. The progress in the screening test program is described, including screening creep results and metallographic analysis for materials thermally exposed or tested at 750, 850, and 950/sup 0/C.

Not Available

1980-06-25T23:59:59.000Z

289

Nuclear design of the burst power ultrahigh temperature UF4 vapor core reactor system  

Science Journals Connector (OSTI)

Static and dynamic neutronic analyses are being performed as part of an integrated series of studies on an innovative burst power UF4 Ultrahigh Temperature Vapor Core Reactor (UTVR)/Disk Magnetohydrodynamic (MHD) generator for space nuclear power applications. This novel reactor concept operates on a direct closed Rankine cycle in the burst power mode (hundreds of MWe for thousands of seconds). The fuel/working fluid is a mixture of UF4 and metal fluoride. Preliminary calculations indicate high overall system efficiencies (?20%) small radiator size (?5 m2/MWe) and high specific power (?5 kWe/kg). Neutronic analysis has revealed a number of attractive features for this novel reactor concept. These include some unique and very effective inherent negative reactivity control mechanisms such as the vapor?fuel density power coefficient of reactivity the direct neutronic coupling among the multiple fissioning core regions (the central vapor core and the surrounding boiler columns) and the mass flow coupling feedback between the fissioning cores.

Samer D. Kahook; Edward T. Dugan

1991-01-01T23:59:59.000Z

290

Design of a Receding Horizon Control System for Nuclear Reactor Power Distribution  

SciTech Connect (OSTI)

A receding horizon control method is applied to the axial power distribution control in a pressurized water reactor. The basic concept of receding horizon control is to solve on-line, at each sampling instant, an optimization problem for a finite future and to implement the first optimal control input as the current control input. Thus, it is a suitable control strategy for time-varying systems. The reactor model used for computer simulations is a two-point xenon oscillation model based on the nonlinear xenon and iodine balance equations and a one-group, one-dimensional, neutron diffusion equation with nonlinear power reactivity feedback that adequately describes axial oscillations and treats the nonlinearities explicitly. The reactor core is axially divided into two regions, and each region has one input and one output and is coupled with the other region. Through numerical simulations, it is shown that the proposed control algorithm exhibits very fast tracking responses due to the step and ramp changes of axial target shape and also works well in a time-varying parameter condition.

Na, Man Gyun [Chosun University (Korea, Republic of)

2001-07-15T23:59:59.000Z

291

A study on reactor core failure thresholds to safety operation of LMFBR  

SciTech Connect (OSTI)

Japan Nuclear Safety Organization (JNES) has been developing the methodology and computer codes for applying level-1 PSA to LMFBR. Many of our efforts have been directed to the judging conditions of reactor core damage and the time allowed to initiate the accident management. Several candidates of the reactor core failure threshold were examined to a typical proto-type LMFBR with MOX fuel based on the plant thermal-hydraulic analyses to the actual progressions leading to the core damage. The results of the present study showed that the judging condition of coolant-boundary integrity failure, 750 degree-C of the boundary temperature, is enough as the threshold of core damage to PLOHS (protected loss-of-heat sink). High-temperature fuel cladding creep failure will not take place before the coolant-boundary reaches the judging temperature and sodium boiling will not occur due to the system pressure rise. In cases of ATWS (anticipated transient without scrum) the accident progression is so fast and the reactor core damage will be inevitable even a realistic negative reactivity insertion due to the temperature rise is considered. Only in the case of ULOHS (unprotected loss-of-heat sink) a relatively long time of 11 min will be allowed till the shut-down of the reactor before the core damage. (authors)

Kazuo, Haga; Hiroshi, Endo; Tomoko, Ishizu; Yoshihisa, Shindo [Japan Nuclear Energy Safety Organization, Safety Analysis and Evaluation Division, Kamiya-cho MT Bldg., 4-3-20, Toranomon, Minato-ku, Tokyo (Japan)

2006-07-01T23:59:59.000Z

292

Power module assemblies with staggered coolant channels  

DOE Patents [OSTI]

A manifold is provided for supporting a power module assembly with a plurality of power modules. The manifold includes a first manifold section. The first face of the first manifold section is configured to receive the first power module, and the second face of the first manifold section defines a first cavity with a first baseplate thermally coupled to the first power module. The first face of the second manifold section is configured to receive the second power module, and the second face of the second manifold section defines a second cavity with a second baseplate thermally coupled to the second power module. The second face of the first manifold section and the second face of the second manifold section are coupled together such that the first cavity and the second cavity form a coolant channel. The first cavity is at least partially staggered with respect to second cavity.

Herron, Nicholas Hayden; Mann, Brooks S; Korich, Mark D

2013-07-16T23:59:59.000Z

293

Superfluid helium as a technical coolant  

E-Print Network [OSTI]

The characteristics of superfluid helium as a technical coolant, which derive from its specific transport properties, are presented with particular reference to the working area in the phase diagram (saturated or pressurised helium II). We then review the principles and scaling laws of heat transport by equivalent conduction and by forced convection in pressurised helium II, thus revealing intrinsic limitations as well as technological shortcomings of these cooling methods. Once properly implemented, two-phase flow of saturated helium II presents overwhelming advantages over the previous solutions, which dictated its choice for cooling below 1.9 K the long strings of superconducting magnets in the Large Hadron Collider (LHC), a 26.7 km circumference particle collider now under construction at CERN, the European Laboratory for Particle Physics near Geneva (Switzerland). We report on recent results from the ongoing research and development programme conducted on thermohydraulics of two-phase saturated helium II...

Lebrun, P

1997-01-01T23:59:59.000Z

294

Testing of organic acids in engine coolants  

SciTech Connect (OSTI)

The effectiveness of 30 organic acids as inhibitors in engine coolants is reported. Tests include glassware corrosion of coupled and uncoupled metals. FORD galvanostatic and cyclic polarization electrochemistry for aluminum pitting, and reserve alkalinity (RA) measurements. Details of each test are discussed as well as some general conclusions. For example, benzoic acid inhibits coupled metals well but is ineffective on cast iron when uncoupled. In benzoic acid inhibits coupled metals well but is ineffective on cast iron when uncoupled. In general, the organic acids provide little RA when titrated to a pH of 5.5, titration to a pH of 4.5 can result in precipitation of the acid. Trends with respect to acid chain length are reported also.

Weir, T.W. [ARCO Chemical Co., Newtown Square, PA (United States)

1999-08-01T23:59:59.000Z

295

Closed Brayton cycle power system with a high temperature pellet bed reactor heat source for NEP applications  

Science Journals Connector (OSTI)

Capitalizing on past and future development of high temperature gas reactor (HTGR) technology a low mass 15 MWe closed gas turbine cycle power system using a pellet bed reactor heating helium working fluid is proposed for Nuclear Electric Propulsion (NEP) applications. Although the design of this directly coupled system architecture comprising the reactor/power system/space radiator subsystems is presented in conceptual form sufficient detail is included to permit an assessment of overall system performance and mass. Furthermore an attempt is made to show how tailoring of the main subsystem design characteristics can be utilized to achieve synergistic system level advantages that can lead to improved reliability and enhanced system life while reducing the number of parasitic load driven peripheral subsystems.

Albert J. Juhasz; Mohamed S. El?Genk; William Harper

1993-01-01T23:59:59.000Z

296

Fleet test evaluation of fully formulated heavy-duty coolant technology maintained with a delayed-release filter compared with coolant inhibited with a nitrited organic acid technology: An interim report  

SciTech Connect (OSTI)

This paper is a controlled extended service interval (ESI) study of the comparative behaviors of a nitrite/borate/low-silicate, low total dissolved solids (TDS) coolant maintained with delayed-release filters, and an organic acid inhibited coolant technology in heavy-duty engines. It reports both laboratory and fleet test data from 66 trucks, powered with different makes of heavy-duty diesel engines. The engines were cooled with three different types of inhibitors and two different glycol base (ethylene glycol and propylene glycol) coolants for an initial period exceeding two years and 500,000 km (300,000 miles). The data reported include chemical depletion rates, periodic coolant chemical analyses, and engine/cooling system reliability experience. The ongoing test will continue for approximately five years and a 1.6 million km (1 million miles) duration. Thirteen trucks were retained as controls, operating with ASTM D 4985 specification (GM-6038 type) coolant maintained with a standard ASTM D 57542 supplemental coolant additive (SCA). Engines produced by Caterpillar, Detroit Diesel Corp., Cummins Engine Co., and Mack Trucks are included in the test mix.

Aroyan, S.S.; Eaton, E.R. [Penray Companies, Inc., Elk Grove Village, IL (United States). Technical Service

1999-08-01T23:59:59.000Z

297

Neutronic analysis of a fusion hybrid reactor  

SciTech Connect (OSTI)

In a PHYSOR 2010 paper(1) we introduced a fusion hybrid reactor whose fusion component is the gasdynamic mirror (GDM), and whose blanket was made of thorium - 232. The thrust of that study was to demonstrate the performance of such a reactor by establishing the breeding of uranium - 233 in the blanket, and the burning thereof to produce power. In that analysis, we utilized the diffusion equation for one-energy neutron group, namely, those produced by the fusion reactions, to establish the power distribution and density in the system. Those results should be viewed as a first approximation since the high energy neutrons are not effective in inducing fission, but contribute primarily to the production of actinides. In the presence of a coolant, however, such as water, these neutrons tend to thermalize rather quickly, hence a better assessment of the reactor performance would require at least a two group analysis, namely the fast and thermal groups. We follow that approach and write an approximate set of equations for the fluxes of these groups. From these relations we deduce the all-important quantity, k{sub eff}, which we utilize to compute the multiplication factor, and subsequently, the power density in the reactor. We show that k{sub eff} can be made to have a value of 0.99, thus indicating that 100 thermal neutrons are generated per fusion neutron, while allowing the system to function as 'subcritical.' Moreover, we show that such a hybrid reactor can generate hundreds of megawatts of thermal power per cm of length depending on the flux of the fusion neutrons impinging on the blanket. (authors)

Kammash, T. [Univ. of Michigan, NERS, 2355 Bonisteel Blvd., Ann Arbor, MI 48109 (United States)

2012-07-01T23:59:59.000Z

298

BISON Enhanced with Improved Models for Cladding and Coolant Channels |  

Broader source: Energy.gov (indexed) [DOE]

Enhanced with Improved Models for Cladding and Coolant Enhanced with Improved Models for Cladding and Coolant Channels BISON Enhanced with Improved Models for Cladding and Coolant Channels January 29, 2013 - 10:54am Addthis Pin-scale Code Development Development of BISON for the engineering-scale simulation of nuclear fuel performance continued. Enhancements during this quarter include implementation of a nonlinear material model for Zircaloy cladding that simultaneously combines the phenomena of plasticity, thermal creep, and irradiation creep; implementation of a complete set of material properties and a creep model for stainless steel cladding; and modification of the coolant sub-channel model to better support simulations of loss-of- coolant-accidents. BISON simulations are being compared to relevant empirical fuel pin data

299

Radiant energy receiver having improved coolant flow control means  

DOE Patents [OSTI]

An improved coolant flow control for use in radiant energy receivers of the type having parallel flow paths is disclosed. A coolant performs as a temperature dependent valve means, increasing flow in the warmer flow paths of the receiver, and impeding flow in the cooler paths of the receiver. The coolant has a negative temperature coefficient of viscosity which is high enough such that only an insignificant flow through the receiver is experienced at the minimum operating temperature of the receiver, and such that a maximum flow is experienced at the maximum operating temperature of the receiver. The valving is accomplished by changes in viscosity of the coolant in response to the coolant being heated and cooled. No remotely operated valves, comparators or the like are needed.

Hinterberger, H.

1980-10-29T23:59:59.000Z

300

Heat Transfer Simulation of Reactor Cavity Cooling System Experimental Facility using RELAP5-3D and Generation of View Factors using MCNP  

E-Print Network [OSTI]

As one of the most attractive reactor types, The High Temperature Gas-cooled Reactor (HTGR) is designed to be passively safe with the incorporation of Reactor Cavity Cooling System (RCCS). In this paper, a RELAP5-3D simulation model is set up based...

Wu, Huali

2013-08-08T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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301

On the estimation of the unknown reactivity coefficients in a CANDU reactor  

Science Journals Connector (OSTI)

A space-time kinetics based inverse architecture method is suggested to analyze the reactivity variations associated with power excursions in a generic CANDU reactor. It is intended to provide diagnosis tools to gain enhanced control thereby ensuring safe operation of the plant. A methodology for analyzing the data available from the in core flux detectors and extracting the unknown reactivity coefficients is presented. The proposed system uses a reference model in conjunction with an optimal estimator. The reference model is composed of a state space representation of the space-time dynamics of neutron flux in the core, based on modal expansion approximation, and a time domain optimal estimator filter. We investigated three different estimation techniques based on recursive prediction error method (RPEM), dual extended Kalman filter (DEKF), and joint extended Kalman filter (JEKF). We compared their applicability to the estimation of coolant-void dynamic reactivity in loss-of-coolant accident in a CANDU reactor. The state equations also include the characteristics of the detector responses. The thermal hydraulic models were not included in the calculations. Two different types of detectors are considered in this analysis, the over prompt responsive Platinum detector of the reactor shutdown systems, and the under delayed responsive Vanadium detector of the flux mapping system.

Lobat Tayebi; Daryoosh Vashaee

2013-01-01T23:59:59.000Z

302

Developing Fully Coupled Dynamical Reactor Core Isolation System Models in RELAP-7 for Extended Station Black-Out Analysis  

SciTech Connect (OSTI)

The reactor core isolation cooling (RCIC) system in a boiling water reactor (BWR) provides makeup water to the reactor vessel for core cooling when the main steam lines are isolated and the normal supply of water to the reactor vessel is lost. It was one of the very few safety systems still available during the Fukushima Daiichi accidents after the tsunamis hit the plants and the system successfully delayed the core meltdown for a few days for unit 2 & 3. Therefore, detailed models for RCIC system components are indispensable to understand extended station black-out accidents (SBO) for BWRs. As part of the effort to develop the new generation reactor system safety analysis code RELAP-7, major components to simulate the RCIC system have been developed. This paper describes the models for those components such as turbine, pump, and wet well. Selected individual component test simulations and a simplified SBO simulation up to but before core damage is presented. The successful implementation of the simplified RCIC and wet well models paves the way to further improve the models for safety analysis by including more detailed physical processes in the near future.

Haihua Zhao; Ling Zou; Hongbin Zhang; David Andrs; Richard Martineau

2014-04-01T23:59:59.000Z

303

Lead-Cooled Fast Reactor (LFR) Design: Safety, Neutronics, Thermal Hydraulics, Structural Mechanics, Fuel, Core, and Plant Design  

SciTech Connect (OSTI)

The idea of developing fast spectrum reactors with molten lead (or lead alloy) as a coolant is not a new one. Although initially considered in the West in the 1950s, such technology was not pursued to completion because of anticipated difficulties associated with the corrosive nature of these coolant materials. However, in the Soviet Union, such technology was actively pursued during the same time frame (1950s through the 1980s) for the specialized role of submarine propulsion. More recently, there has been a renewal of interest in the West for such technology, both for critical systems as well as for Accelerator Driven Subcritical (ADS) systems. Meanwhile, interest in the former Soviet Union, primarily Russia, has remained strong and has expanded well beyond the original limited mission of submarine propulsion. This section reviews the past and current status of LFR development.

Smith, C

2010-02-22T23:59:59.000Z

304

Safe new reactor for radionuclide production  

SciTech Connect (OSTI)

In late 1995, DOE is schedule to announce a new tritium production unit. Near the end of the last NPR (New Production Reactors) program, work was directed towards eliminating risks in current designs and reducing effects of accidents. In the Heavy Water Reactor Program at Savannah River, the coolant was changed from heavy to light water. An alternative, passively safe concept uses a heavy-water-filled, zircaloy reactor calandria near the bottom of a swimming pool; the calandria is supported on a light-water-coolant inlet plenum and has upflow through assemblies in the calandria tubes. The reactor concept eliminates or reduces significantly most design basis and severe accidents that plague other deigns. The proven, current SRS tritium cycle remains intact; production within the US of medical isotopes such as Mo-99 would also be possible.

Gray, P.L.

1995-02-15T23:59:59.000Z

305

Consortium for Advanced Simulation of Light Water Reactors (CASL...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Shortly after that modeling prediction, a significant-sized sample of that actual phase material was discovered in the coolant system of an LWR. This instance is encouraging...

306

Heat removal aspects of Liquid Metal Fast Breeder Reactor safety in light of the Three Mile Island incident  

SciTech Connect (OSTI)

The safety aspects of the Liquid Metal Fast Breeder Reactor (LMFBR) loop design are compared with those of the Light Water Reactor (LWR), in light of the Three Mile Island (TMI) incident. The events at TMI are briefly described, the fundamental differences between the LWR water coolant and the LMFBR sodium coolant are presented, and the design of analogous LMFBR safety systems under similar events as those at TMI is discussed. A preliminary qualitative evaluation of a TMI-equivalent accident for an LMFBR indicates that there is likely to be: (1) negligible pressure transients in the primary loop, (2) no core damage, (3) isolation of the incident at the steam generator, and (4) no radiation release to the environment, except a negligible amount of tritium from the secondary sodium. Furthermore, with the absence of the ECCS (Emergency Core Cooling System), pressurizer, and other pressure-related components in the LMFBR design, operator action for a LMFBR should be much simpler in dealing with the coolant upset condition and the decay heat removal problems.

Victor, H.R.; Graf, D.G.

1980-12-01T23:59:59.000Z

307

Barriers to the Application of High-Temperature Coolants in Hybrid Electric Vehicles  

SciTech Connect (OSTI)

This study was performed by the Oak Ridge National Laboratory (ORNL) to identify practical approaches, technical barriers, and cost impacts to achieving high-temperature coolant operation for certain traction drive subassemblies and components of hybrid electric vehicles (HEV). HEVs are unique in their need for the cooling of certain dedicated-traction drive subassemblies/components that include the electric motor(s), generators(s), inverter, dc converter (where applicable), and dc-link capacitors. The new coolant system under study would abandon the dedicated 65 C coolant loop, such as used in the Prius, and instead rely on the 105 C engine cooling loop. This assessment is important because automotive manufacturers are interested in utilizing the existing water/glycol engine cooling loop to cool the HEV subassemblies in order to eliminate an additional coolant loop with its associated reliability, space, and cost requirements. In addition, the cooling of power electronic devices, traction motors, and generators is critical in meeting the U.S. Department of Energy (DOE) FreedomCAR and Vehicle Technology (FCVT) goals for power rating, volume, weight, efficiency, reliability, and cost. All of these have been addressed in this study. Because there is high interest by the original equipment manufacturers (OEMs) in reducing manufacturing cost to enhance their competitive standing, the approach taken in this analysis was designed to be a positive 'can-do' approach that would be most successful in demonstrating the potential or opportunity of relying entirely on a high-temperature coolant system. Nevertheless, it proved to be clearly evident that a few formidable technical and cost barriers exist and no effective approach for mitigating the barriers was evident in the near term. Based on comprehensive thermal tests of the Prius reported by ORNL in 2005 [1], the continuous ratings at base speed (1200 rpm) with different coolant temperatures were projected from test data at 900 rpm. They are approximately 15 kW with 103 C coolant and 20 kW with 50 C coolant. To avoid this 25% drop1 in continuous power, design changes for improved heat dissipation and carefully managed changes in allowable thermal limits would be required in the hybrid subsystems. This study is designed to identify the technical barriers that potentially exist in moving to a high-temperature cooling loop prior to addressing the actual detailed design. For operation at a significantly higher coolant temperature, there were component-level issues that had to be addressed in this study. These issues generally pertained to the cost and reliability of existing or near term components that would be suitable for use with the 105 C coolant. The assessed components include power electronic devices/modules such as diodes and insulated-gate bipolar transistors (IGBTs), inverter-grade high-temperature capacitors, permanent magnets (PM), and motor-grade wire insulation. The need for potentially modifying/resizing subassemblies such as inverters, motors, and heat exchangers was also addressed in the study. In order to obtain pertinent information to assist ORNL researchers address the thermal issues at the component, module, subassembly, and system levels, pre-existing laboratory test data conducted at varying temperatures was analyzed in conjunction with information obtained from technical literature searches and industry sources.

Hsu, J.S.; Staunton, M.R.; Starke, M.R.

2006-09-30T23:59:59.000Z

308

Barriers to the Application of High-Temperature Coolants in Hybrid Electric Vehicles  

SciTech Connect (OSTI)

This study was performed by the Oak Ridge National Laboratory (ORNL) to identify practical approaches, technical barriers, and cost impacts to achieving high-temperature coolant operation for certain traction drive subassemblies and components of hybrid electric vehicles (HEV). HEVs are unique in their need for the cooling of certain dedicated-traction drive subassemblies/components that include the electric motor(s), generators(s), inverter, dc converter (where applicable), and dc-link capacitors. The new coolant system under study would abandon the dedicated 65 C coolant loop, such as used in the Prius, and instead rely on the 105 C engine cooling loop. This assessment is important because automotive manufacturers are interested in utilizing the existing water/glycol engine cooling loop to cool the HEV subassemblies in order to eliminate an additional coolant loop with its associated reliability, space, and cost requirements. In addition, the cooling of power electronic devices, traction motors, and generators is critical in meeting the U.S. Department of Energy (DOE) FreedomCAR and Vehicle Technology (FCVT) goals for power rating, volume, weight, efficiency, reliability, and cost. All of these have been addressed in this study. Because there is high interest by the original equipment manufacturers (OEMs) in reducing manufacturing cost to enhance their competitive standing, the approach taken in this analysis was designed to be a positive 'can-do' approach that would be most successful in demonstrating the potential or opportunity of relying entirely on a high-temperature coolant system. Nevertheless, it proved to be clearly evident that a few formidable technical and cost barriers exist and no effective approach for mitigating the barriers was evident in the near term. Based on comprehensive thermal tests of the Prius reported by ORNL in 2005 [1], the continuous ratings at base speed (1200 rpm) with different coolant temperatures were projected from test data at 900 rpm. They are approximately 15 kW with 103 C coolant and 20 kW with 50 C coolant. To avoid this 25% drop1 in continuous power, design changes for improved heat dissipation and carefully managed changes in allowable thermal limits would be required in the hybrid subsystems. This study is designed to identify the technical barriers that potentially exist in moving to a high-temperature cooling loop prior to addressing the actual detailed design. For operation at a significantly higher coolant temperature, there were component-level issues that had to be addressed in this study. These issues generally pertained to the cost and reliability of existing or near-term components that would be suitable for use with the 105 C coolant. The assessed components include power electronic devices/modules such as diodes and insulated-gate bipolar transistors (IGBTs), inverter-grade high-temperature capacitors, permanent magnets (PM), and motor-grade wire insulation. The need for potentially modifying/resizing subassemblies such as inverters, motors, and heat exchangers was also addressed in the study. In order to obtain pertinent information to assist ORNL researchers address the thermal issues at the component, module, subassembly, and system levels, pre-existing laboratory test data conducted at varying temperatures was analyzed in conjunction with information obtained from technical literature searches and industry sources.

Staunton, Robert H [ORNL; Hsu, John S [ORNL; Starke, Michael R [ORNL

2006-09-01T23:59:59.000Z

309

Criticality prevention during postaccident decontamination of TMI-2 (Three Mile Island Unit 2) plant systems  

SciTech Connect (OSTI)

Following the accident at Three Mile Island Unit 2 (TMI-2), the likelihood of a criticality outside of the reactor coolant system (RCS) during the plant cleanup was very small. Given the consequence of any possible critical event in the TMI-2 systems, However, it was always necessary to ensure that all steps were taken to prevent criticality. Therefore, engineered controls were developed to ensure that decontamination of plant systems containing fuel material could be conducted in a manner that precluded criticality.

Palau, G. L.

1988-01-01T23:59:59.000Z

310

Cladding embrittlement during postulated loss-of-coolant accidents.  

SciTech Connect (OSTI)

The effect of fuel burnup on the embrittlement of various cladding alloys was examined with laboratory tests conducted under conditions relevant to loss-of-coolant accidents (LOCAs). The cladding materials tested were Zircaloy-4, Zircaloy-2, ZIRLO, M5, and E110. Tests were performed with specimens sectioned from as-fabricated cladding, from prehydrided (surrogate for high-burnup) cladding, and from high-burnup fuel rods which had been irradiated in commercial reactors. The tests were designed to determine for each cladding material the ductile-to-brittle transition as a function of steam oxidation temperature, weight gain due to oxidation, hydrogen content, pre-transient cladding thickness, and pre-transient corrosion-layer thickness. For short, defueled cladding specimens oxidized at 1000-1200 C, ring compression tests were performed to determine post-quench ductility at {le} 135 C. The effect of breakaway oxidation on embrittlement was also examined for short specimens oxidized at 800-1000 C. Among other findings, embrittlement was found to be sensitive to fabrication processes--especially surface finish--but insensitive to alloy constituents for these dilute zirconium alloys used as cladding materials. It was also demonstrated that burnup effects on embrittlement are largely due to hydrogen that is absorbed in the cladding during normal operation. Some tests were also performed with longer, fueled-and-pressurized cladding segments subjected to LOCA-relevant heating and cooling rates. Recommendations are given for types of tests that would identify LOCA conditions under which embrittlement would occur.

Billone, M.; Yan, Y.; Burtseva, T.; Daum, R.; Nuclear Engineering Division

2008-07-31T23:59:59.000Z

311

Analysis of Loss-of-Coolant Accidents in the NBSR  

SciTech Connect (OSTI)

This report documents calculations of the fuel cladding temperature during loss-of-coolant accidents in the NBSR. The probability of a pipe failure is small and procedures exist to minimize the loss of water and assure emergency cooling water flows into the reactor core during such an event. Analysis in the past has shown that the emergency cooling water would provide adequate cooling if the water filled the flow channels within the fuel elements. The present analysis is to determine if there is adequate cooling if the water drains from the flow channels. Based on photographs of how the emergency water flows into the fuel elements from the distribution pan, it can be assumed that this water does not distribute uniformly across the flow channels but rather results in a liquid film flowing downward on the inside of one of the side plates in each fuel element and only wets the edges of the fuel plates. An analysis of guillotine breaks shows the cladding temperature remains below the blister temperature in fuel plates in the upper section of the fuel element. In the lower section, the fuel plates are also cooled by water outside the element that is present due to the hold-up pan and temperatures are lower than in the upper section. For small breaks, the simulation results show that the fuel elements are always cooled on the outside even in the upper section and the cladding temperature cannot be higher than the blister temperature. The above results are predicated on assumptions that are examined in the study to see their influence on fuel temperature.

Baek J. S.; Cheng L.; Diamond, D.

2014-05-23T23:59:59.000Z

312

Functional issues and environmental qualification of digital protection systems of advanced light-water nuclear reactors  

SciTech Connect (OSTI)

Issues of obsolescence and lack of infrastructural support in (analog) spare parts, coupled with the potential benefits of digital systems, are driving the nuclear industry to retrofit analog instrumentation and control (I&C) systems with digital and microprocessor-based systems. While these technologies have several advantages, their application to safety-related systems in nuclear power plants raises key issues relating to the systems` environmental qualification and functional reliability. To bound the problem of new I&C system functionality and qualification, the authors focused this study on protection systems proposed for use in ALWRs. Specifically, both functional and environmental qualification issues for ALWR protection system I&C were addressed by developing an environmental, functional, and aging data template for a protection division of each proposed ALWR design. By using information provided by manufacturers, environmental conditions and stressors to which I&C equipment in reactor protection divisions may be subjected were identified. The resulting data were then compared to a similar template for an instrument string typically found in an analog protection division of a present-day nuclear power plant. The authors also identified fiber-optic transmission systems as technologies that are relatively new to the nuclear power plant environment and examined the failure modes and age-related degradation mechanisms of fiber-optic components and systems. One reason for the exercise of caution in the introduction of software into safety-critical systems is the potential for common-cause failure due to the software. This study, however, approaches the functionality problem from a systems point of view. System malfunction scenarios are postulated to illustrate the fact that, when dealing with the performance of the overall integrated system, the real issues are functionality and fault tolerance, not hardware vs. software.

Korsah, K.; Clark, R.L.; Wood, R.T. [Oak Ridge National Lab., TN (United States)

1994-04-01T23:59:59.000Z

313

The application of Plant Reliability Data Information System (PRINS) to CANDU reactor  

SciTech Connect (OSTI)

As risk-informed applications (RIAs) are actively implanted in the nuclear industry, an issue associated with technical adequacy of Probabilistic Safety Assessment (PSA) arises in its modeling and data sourcing. In Korea, PSA for all Korean NPPs has been completed and KHNP(Korea Hydro and Nuclear Power Plant Company) developed the database called the Plant Reliability Data Information System (PRinS). It has several characteristics that distinguish it from other database system such as NPRDs (INPO,1994), PRIS (IAEA), and SRDF (EdF). This database has the function of systematic data management such as automatic data-gathering, periodic data deposition and updating, statistical analysis including Bayesian method, and trend analysis of failure rate or unavailability. In recent PSA for CANDU reactor, the component failure data of EPRI ALWR URD and Component Reliability Database were preferentially used as generic data set. The error factor for most component failure data was estimated by using the information NUREG/CR-4550 and NUREG/CR-4639. Also, annual trend analysis was performed for the functional losses of components using the statistical analysis and chart module of PRinS. Furthermore, the database has been updated regularly and maintained as a living program to reflect the current status. This paper presents the failure data analysis using PRinS which provides Bayesian analysis on main components in the CANDU reactor. (authors)

Hwang, S. W.; Lim, Y. H.; Park, H. C. [Korea Hydro and Nuclear Power Co., Ltd., Naah-ri 260, Yangnam-myun, Gyeongju-si, Gyeong Buk (Korea, Republic of)

2012-07-01T23:59:59.000Z

314

High Temperature Water Heat Pipes Radiator for a Brayton Space Reactor Power System  

SciTech Connect (OSTI)

A high temperature water heat pipes radiator design is developed for a space power system with a sectored gas-cooled reactor and three Closed Brayton Cycle (CBC) engines, for avoidance of single point failures in reactor cooling and energy conversion and rejection. The CBC engines operate at turbine inlet and exit temperatures of 1144 K and 952 K. They have a net efficiency of 19.4% and each provides 30.5 kWe of net electrical power to the load. A He-Xe gas mixture serves as the turbine working fluid and cools the reactor core, entering at 904 K and exiting at 1149 K. Each CBC loop is coupled to a reactor sector, which is neutronically and thermally coupled, but hydraulically decoupled to the other two sectors, and to a NaK-78 secondary loop with two water heat pipes radiator panels. The segmented panels each consist of a forward fixed segment and two rear deployable segments, operating hydraulically in parallel. The deployed radiator has an effective surface area of 203 m2, and when the rear segments are folded, the stowed power system fits in the launch bay of the DELTA-IV Heavy launch vehicle. For enhanced reliability, the water heat pipes operate below 50% of their wicking limit; the sonic limit is not a concern because of the water, high vapor pressure at the temperatures of interest (384 - 491 K). The rejected power by the radiator peaks when the ratio of the lengths of evaporator sections of the longest and shortest heat pipes is the same as that of the major and minor widths of the segments. The shortest and hottest heat pipes in the rear segments operate at 491 K and 2.24 MPa, and each rejects 154 W. The longest heat pipes operate cooler (427 K and 0.52 MPa) and because they are 69% longer, reject more power (200 W each). The longest and hottest heat pipes in the forward segments reject the largest power (320 W each) while operating at {approx} 46% of capillary limit. The vapor temperature and pressure in these heat pipes are 485 K and 1.97 MPa. By contrast, the shortest water heat pipes in the forward segments operate much cooler (427 K and 0.52 MPa), and reject a much lower power of 45 W each. The radiator with six fixed and 12 rear deployable segments rejects a total of 324 kWth, weights 994 kg and has an average specific power of 326 Wth/kg and a specific mass of 5.88 kg/m2.

El-Genk, Mohamed S.; Tournier, Jean-Michel [Institute for Space and Nuclear Power Studies, University of New Mexico, Albuquerque, NM 87131 (United States); Chemical and Nuclear Engineering Department, University of New Mexico, Albuquerque, NM 87131 (United States)

2006-01-20T23:59:59.000Z

315

Vented target elements for use in an isotope-production reactor. [LMFBR  

DOE Patents [OSTI]

A method is described for producing tritium gas in a fast breeder reactor cooled with liquid metal. Lithium target material is placed in pins equipped with vents, and tritium gas is recovered from the coolant.

Cawley, W.E.; Omberg, R.P.

1982-08-19T23:59:59.000Z

316

Conceptual Design of Molten Salt Loop Experiment for MIT Research Reactor  

E-Print Network [OSTI]

Molten salt is a promising coolant candidate for Advanced High Temperature Reactor (AHTR) Gen-IV designs. The low neutron absorption, high thermal capacity, chemical inertness, and high boiling point at low pressure of ...

Bean, Malcolm K.

2011-08-01T23:59:59.000Z

317

Stability analysis of the boiling water reactor : methods and advanced designs  

E-Print Network [OSTI]

Density Wave Oscillations (DWOs) are known to be possible when a coolant undergoes considerable density reduction while passing through a heated channel. In the development of boiling water reactors (BWRs), there has been ...

Hu, Rui, Ph. D. Massachusetts Institute of Technology

2010-01-01T23:59:59.000Z

318

Single channel flow blockage accident phenomena identification and ranking table (PIRT) for the advanced Candu reactor  

SciTech Connect (OSTI)

The Advanced Candu Reactor (ACRTM) is an evolutionary advancement of the current Candu 6{sup R} reactor, aimed at producing electrical power for a capital cost and at a unit-energy cost significantly less than that of the current reactor designs. The ACR retains the modular concept of horizontal fuel channels surrounded by a heavy water moderator, as with all Candu reactors. However, ACR uses slightly enriched uranium (SEU) fuel, compared to the natural uranium used in Candu 6. This achieves the twin goals of improved economics (e.g., via reductions in the heavy water requirements and the use of a light water coolant), as well as improved safety. This paper documents the results of Phenomena Identification and Ranking Table (PIRT) results for a very limited frequency, beyond design basis event of the ACR design. This PIRT is developed in a highly structured process of expert elicitation that is well supported by experimental data and analytical results. The single-channel flow blockage event in an ACR reactor assumes a severe flow blockage of one of the reactor fuel channels, which leads to a reduction of the flow in the affected channel, leading to fuel cladding and fuel temperature increase. The paper outlines the design characteristics of the ACR reactor that impact the PIRT process and computer code applicability. It also describes the flow blockage phenomena, lists all components and systems that have an important role during the event, discusses the PIRT process and results, and presents the finalized PIRT tables. (authors)

Popov, N.K.; Abdul-Razzak, A.; Snell, V.G.; Langman, V. [Atomic Energy of Canada Ltd., 2251 Speakman Drive, Mississauga, Ontario, L5K 1B2 (Canada); Sills, H. [Consultant, Deep River, Ontario (Canada)

2004-07-01T23:59:59.000Z

319

Computational Fluid Dynamics Analysis of Very High Temperature Gas-Cooled Reactor Cavity Cooling System  

SciTech Connect (OSTI)

The design of passive heat removal systems is one of the main concerns for the modular very high temperature gas-cooled reactors (VHTR) vessel cavity. The reactor cavity cooling system (RCCS) is a key heat removal system during normal and off-normal conditions. The design and validation of the RCCS is necessary to demonstrate that VHTRs can survive to the postulated accidents. The computational fluid dynamics (CFD) STAR-CCM+/V3.06.006 code was used for three-dimensional system modeling and analysis of the RCCS. A CFD model was developed to analyze heat exchange in the RCCS. The model incorporates a 180-deg section resembling the VHTR RCCS experimentally reproduced in a laboratory-scale test facility at Texas A&M University. All the key features of the experimental facility were taken into account during the numerical simulations. The objective of the present work was to benchmark CFD tools against experimental data addressing the behavior of the RCCS following accident conditions. Two cooling fluids (i.e., water and air) were considered to test the capability of maintaining the RCCS concrete walls' temperature below design limits. Different temperature profiles at the reactor pressure vessel (RPV) wall obtained from the experimental facility were used as boundary conditions in the numerical analyses to simulate VHTR transient evolution during accident scenarios. Mesh convergence was achieved with an intensive parametric study of the two different cooling configurations and selected boundary conditions. To test the effect of turbulence modeling on the RCCS heat exchange, predictions using several different turbulence models and near-wall treatments were evaluated and compared. The comparison among the different turbulence models analyzed showed satisfactory agreement for the temperature distribution inside the RCCS cavity medium and at the standpipes walls. For such a complicated geometry and flow conditions, the tested turbulence models demonstrated that the realizable k-epsilon model with two-layer all y+ wall treatment performs better than the other k-epsilon and k-omega turbulence models when compared to the experimental results and the Reynolds stress transport turbulence model results. A scaling analysis was developed to address the distortions introduced by the CFD model in simulating the physical phenomena inside the RCCS system with respect to the full plant configuration. The scaling analysis demonstrated that both the experimental facility and the CFD model achieve a satisfactory resemblance of the main flow characteristics inside the RCCS cavity region, and convection and radiation heat exchange phenomena are properly scaled from the actual plant.

Angelo Frisani; Yassin A. Hassan; Victor M. Ugaz

2010-11-02T23:59:59.000Z

320

A high-speed data acquisition system to measure low-level current from self-powered flux detectors in CANDU nuclear reactors  

E-Print Network [OSTI]

A high-speed data acquisition system to measure low-level current from self-powered flux detectors in CANDU nuclear reactors

Lawrence, C B

1982-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

The Programmable Logic Controller and its application in nuclear reactor systems  

SciTech Connect (OSTI)

This document provides recommendations to guide reviewers in the application of Programmable Logic Controllers (PLCS) to the control, monitoring and protection of nuclear reactors. The first topics addressed are system-level design issues, specifically including safety. The document then discusses concerns about the PLC manufacturing organization and the protection system engineering organization. Supplementing this document are two appendices. Appendix A summarizes PLC characteristics. Specifically addressed are those characteristics that make the PLC more suitable for emergency shutdown systems than other electrical/electronic-based systems, as well as characteristics that improve reliability of a system. Also covered are PLC characteristics that may create an unsafe operating environment. Appendix B provides an overview of the use of programmable logic controllers in emergency shutdown systems. The intent is to familiarize the reader with the design, development, test, and maintenance phases of applying a PLC to an ESD system. Each phase is described in detail and information pertinent to the application of a PLC is pointed out.

Palomar, J.; Wyman, R. [Lawrence Livermore National Lab., CA (United States)

1993-09-01T23:59:59.000Z

322

Longer life for glyco-based stationary engine coolants  

SciTech Connect (OSTI)

Large, stationary diesel engines used to compress natural gas that is to be transported down pipelines generate a great deal of heat. Unless this heat is dissipated efficiently, it will eventually cause an expensive breakdown. Whether the coolant uses ethylene glycol or propylene glycol, the two major causes of glycol degradation are heat and oxidation. The paper discusses inhibitors that enhance coolant service life and presents a comprehensive list of do`s and don`ts for users to gain a 20-year coolant life.

Hohlfeld, R. [Dow Chemical Co., Houston, TX (United States)

1996-07-01T23:59:59.000Z

323

Continuous production of tritium in an isotope-production reactor with a separate circulation system  

DOE Patents [OSTI]

A method is described for producing tritium in a fast breeder reactor cooled with liquid metal. Lithium is allowed to flow through the reactor in separate loops in order to facilitate the production and removal of tritium.

Cawley, W.E.; Omberg, R.P.

1982-08-19T23:59:59.000Z

324

SYSTEMS MODELING OF AMMONIA BORANE BEAD REACTOR FOR OFF-BOARD REGENERABLE HYDROGEN STORAGE IN PEM FUEL CELL APPLICATIONS  

SciTech Connect (OSTI)

Out of the materials available for chemical hydrogen storage in PEM fuel cell applications, ammonia borane (AB, NH3BH3) has a high hydrogen storage capacity (upto 19.6% by weight for the release of three hydrogen molecules). Therefore, AB was chosen in our chemical hydride simulation studies. A model for the AB bead reactor system was developed to study the system performance and determine the energy, mass and volume requirements for off-board regenerable hydrogen storage. The system includes hot and cold augers, ballast tank and reactor, product tank, H2 burner and a radiator. One dimensional models based on conservation of mass, species and energy were used to predict important state variables such as reactant and product concentrations, temperatures of various components, flow rates, along with pressure in the reactor system. Control signals to various components are governed by a control system which is modeled as an independent subsystem. Various subsystem components in the models were coded as C language S-functions and implemented in Matlab/Simulink environment. Preliminary system simulation results for a start-up case and for a transient drive cycle indicate accurate trends in the reactor system dynamics.

Brooks, Kriston P.; Devarakonda, Maruthi N.; Rassat, Scot D.; King, Dale A.; Herling, Darrell R.

2010-06-01T23:59:59.000Z

325

Comparative Fuel Cycle Analysis of Critical and Subcritical Fast Reactor Transmutation Systems  

SciTech Connect (OSTI)

Fuel cycle analyses are performed to evaluate the impacts of further transmutation of spent nuclear fuel on high-level and low-level waste mass flows into repositories, on the composition and toxicity of the high-level waste, on the capacity of high-level waste repositories, and on the proliferation resistance of the high-level waste. Storage intact of light water reactor (LWR) spent nuclear fuel, a single recycle in a LWR of the plutonium as mixed-oxide fuel, and the repeated recycle of the transuranics in critical and subcritical fast reactors are compared with the focus on the waste management performance of these systems. Other considerations such as cost and technological challenges were beyond the scope of this study. The overall conclusion of the studies is that repeated recycling of the transuranics from spent nuclear fuel would significantly increase the capacity of high-level waste repositories per unit of nuclear energy produced, significantly increase the nuclear energy production per unit mass of uranium ore mined, significantly reduce the radiotoxicity of the waste streams per unit of nuclear energy produced, and significantly enhance the proliferation resistance of the material stored in high-level waste repositories.

Hoffman, Edward A.; Stacey, Weston M. [Georgia Institute of Technology (United States)

2003-10-15T23:59:59.000Z

326

Core and System Design of Reduced-Moderation Water Reactor with Passive Safety Features  

SciTech Connect (OSTI)

In order to ensure the sustainable energy supply in Japan, research and developments of reduced-moderation water reactor (RMWR) have been performed. The RMWR can attain the favorable characteristics such as high burn-up, long operation cycle, multiple recycling of plutonium and effective utilization of uranium resources, based on the matured LWR technologies. MOX fuel assemblies in the tight-lattice fuel rod arrangement are used to reduce the moderation of neutron, and hence, to increase the conversion ratio. The conceptual design has been accomplished for the small 330 MWe RMWR core with the discharge burn-up of 60 GWd/t and the operation cycle of 24 months, under the natural circulation cooling of the core. A breeding ratio of 1.01 and the negative void reactivity coefficient are simultaneously realized in the design. In the plant system design, the passive safety features are intended to be utilized mainly to improve the economy. At present, a hybrid one under the combination of the passive and the active components, and a fully passive one are proposed. The former has been evaluated to reduce the cost for the reactor components. (authors)

Iwamura, Takamichi; Okubo, Tsutomu; Yonomoto, Taisuke [Japan Atomic Energy Research Institute, Tokai-mura, Naka-gun, Ibaraki-ken, 319-1195 (Japan); Takeda, Renzo; Moriya, Kumiaki [Hitachi, Ltd. (Japan); Kanno, Minoru [The Japan Atomic Power Company (Japan)

2002-07-01T23:59:59.000Z

327

System and method for generating steady state confining current for a toroidal plasma fusion reactor  

DOE Patents [OSTI]

A system for generating steady state confining current for a toroidal plasma fusion reactor providing steady-state generation of the thermonuclear power. A dense, hot toroidal plasma is initially prepared with a confining magnetic field with toroidal and poloidal components. Continuous wave RF energy is injected into said plasma to establish a spectrum of traveling waves in the plasma, where the traveling waves have momentum components substantially either all parallel, or all anti-parallel to the confining magnetic field. The injected RF energy is phased to couple to said traveling waves with both a phase velocity component and a wave momentum component in the direction of the plasma traveling wave components. The injected RF energy has a predetermined spectrum selected so that said traveling waves couple to plasma electrons having velocities in a predetermined range .DELTA.. The velocities in the range are substantially greater than the thermal electron velocity of the plasma. In addition, the range is sufficiently broad to produce a raised plateau having width .DELTA. in the plasma electron velocity distribution so that the plateau electrons provide steady-state current to generate a poloidal magnetic field component sufficient for confining the plasma. In steady state operation of the fusion reactor, the fusion power density in the plasma exceeds the power dissipated in the plasma.

Fisch, Nathaniel J. (Cambridge, MA)

1981-01-01T23:59:59.000Z

328

System and method for generating steady state confining current for a toroidal plasma fusion reactor  

DOE Patents [OSTI]

A system for generating steady state confining current for a toroidal plasma fusion reactor providing steady-state generation of the thermonuclear power. A dense, hot toroidal plasma is initially prepared with a confining magnetic field with toroidal and poloidal components. Continuous wave RF energy is injected into said plasma to estalish a spectrum of traveling waves in the plasma, where the traveling waves have momentum components substantially either all parallel, or all anti-parallel to the confining magnetic field. The injected RF energy is phased to couple to said traveling waves with both a phase velocity component and a wave momentum component in the direction of the plasma traveling wave components. The injected RF energy has a predetermined spectrum selected so that said traveling waves couple to plasma electrons having velocities in a predetermined range .DELTA.. The velocities in the range are substantially greater than the thermal electron velocity of the plasma. In addition, the range is sufficiently broad to produce a raised plateau having width .DELTA. in the plasma electron velocity distribution so that the plateau electrons provide steady-state current to generate a poloidal magnetic field component sufficient for confining the plasma. In steady state operation of the fusion reactor, the fusion power density in the plasma exceeds the power dissipated inthe plasma.

Bers, Abraham (Arlington, MA)

1981-01-01T23:59:59.000Z

329

Nuclear reactor fuel assembly duct-tube-to-handling-socket attachment system  

DOE Patents [OSTI]

A reusable system for removably attaching the upper end 10of a nuclear reactor duct tube to the lower end 30 of a nuclear reactor fuel assembly handling socket. A transition ring 20, fixed to the duct tube's upper end 10, has an interior-threaded section 22 with a first locking hole segment 24. An adaptor ring 40, fixed to the handling socket's lower end 30 has an outside-threaded section 42 with a second locking hole segment 44. The inside 22 and outside 42 threaded sections match and can be joined so that the first 24 and second 44 locking hole segments can be aligned to form a locking hole. A locking ring 50, with a locking pin 52, slides over the adaptor ring 40 so that the locking pin 52 fits in the locking hole. A swage lock 60 or a cantilever finger lock 70 is formed from the locking cup collar 26 to fit in a matching groove 54 or 56 in the locking ring 50 to prevent the locking ring's locking pin 52 from backing out of the locking hole.

Christiansen, David W. (Kennewick, WA); Smith, Bob G. (Kennewick, WA)

1982-01-01T23:59:59.000Z

330

Gas-cooled nuclear reactor  

DOE Patents [OSTI]

A gas-cooled nuclear reactor includes a central core located in the lower portion of a prestressed concrete reactor vessel. Primary coolant gas flows upward through the core and into four overlying heat-exchangers wherein stream is generated. During normal operation, the return flow of coolant is between the core and the vessel sidewall to a pair of motor-driven circulators located at about the bottom of the concrete pressure vessel. The circulators repressurize the gas coolant and return it back to the core through passageways in the underlying core structure. If during emergency conditions the primary circulators are no longer functioning, the decay heat is effectively removed from the core by means of natural convection circulation. The hot gas rising through the core exits the top of the shroud of the heat-exchangers and flows radially outward to the sidewall of the concrete pressure vessel. A metal liner covers the entire inside concrete surfaces of the concrete pressure vessel, and cooling tubes are welded to the exterior or concrete side of the metal liner. The gas coolant is in direct contact with the interior surface of the metal liner and transfers its heat through the metal liner to the liquid coolant flowing through the cooling tubes. The cooler gas is more dense and creates a downward convection flow in the region between the core and the sidewall until it reaches the bottom of the concrete pressure vessel when it flows radially inward and up into the core for another pass. Water is forced to flow through the cooling tubes to absorb heat from the core at a sufficient rate to remove enough of the decay heat created in the core to prevent overheating of the core or the vessel.

Peinado, Charles O. (La Jolla, CA); Koutz, Stanley L. (San Diego, CA)

1985-01-01T23:59:59.000Z

331

Design, development, and applications of a low-cost, dynamic neutron radiography system utilizing the TAMU NSC TRIGA reactor  

E-Print Network [OSTI]

partial fulfilment of the requirements for the degree of MASTER OF SC'IENCE May 1990 Major Subject: Nuclear Engineering DESIGN, DEVELOPMENT. AND APPLICATIONS OF A LOW ? COST, DYNAMIC NEUTRON RADIOGRAPHY SYSTEM UTILIZING THE TAMU NSC TRIGA REACTOR A...DESIGN, DEVELOPMENT. AND APPLICATIONS OF A LOW ? COST, DYNAMIC NEUTRON RADIOGRAPHY SYSTEM UTILIZING THE TAMU NSC TRIGA REACTOR A Thesis SC'OTT PATRIC'If ItIIDGETT Submitted to the Ofhce of Graduate Studies of Texas AklVI I!niversity rn...

Midgett, Scott Patrick

2012-06-07T23:59:59.000Z

332

Modeling and small-break loss-of-coolant accident analysis of Comanche Peak Steam Electric Station using RELAP5/MOD2  

E-Print Network [OSTI]

. This model was based on a sensitivity study which was performed on the nodalization of the reactor core and the steam generator. The sensitivity study indicates that the RELAP5 reactor vessel model is nodalization independent for steady-state calculations...-of-Coolant Accident 7 Comparison of RELAP5 and RETRAN Reactor Vessel Results . . . , . . . 55 57 57 59 65 68 8 Comparison of RELAP5 and RETRAN Steam Generator Primary Side Results. 9 Comparison of RELAP and RETRAN Steam Generator Secondary Side Results. 69...

Salim, Parvez

2012-06-07T23:59:59.000Z

333

Assessment of passive safety system performance under gravity driven cooling system drain line break accident  

Science Journals Connector (OSTI)

Abstract A generation III+ Boiling Water Reactor (BWR) which relies on natural circulation has evolved from earlier BWR designs by incorporating passive safety features to improve safety and performance. Natural circulation allows the elimination of emergency injection pump and no operator action or alternating current (AC) power supply. The generation III+ BWR's passive safety systems include the Automatic Depressurization System (ADS), the Suppression Pool (SP), the Standby Liquid Control System (SLCS), the Gravity Driven Cooling System (GDCS), the Isolation Condenser System (ICS) and the Passive Containment Cooling System (PCCS). The ADS is actuated to rapidly depressurize the reactor leading to the GDCS injection. The large amount of water in the SP condenses steam from the reactor. The SLCS provides makeup water to the reactor. The GDCS injects water into the reactor by gravity head and provides cooling to the core. The ICS and the PCCS are used to remove the decay heat from the reactor. The objective of this paper is to analyze the response of passive safety systems under the Loss of Coolant Accident (LOCA). A GDCS Drain Line Break (GDLB) test has been conducted in the Purdue University Multi-Dimensional Integral Test Assembly (PUMA) which is scaled to represent the generation III+ BWR. The main results of PUMA GDLB test were that the reactor coolant level was well above the Top of Active Fuel (TAF) and the reactor containment pressure has remained below the design pressure. In particular, the containment maximum pressure (266 kPa) was 36% lower than the safety limit (414 kPa). The minimum collapsed water level (1.496 m) before the GDCS injection was 8% lower than the TAF (1.623 m) but it was ensured that two-phase water level was higher than the TAF with no core uncovery.

J. Lim; J. Yang; S.W. Choi; D.Y. Lee; S. Rassame; T. Hibiki; M. Ishii

2014-01-01T23:59:59.000Z

334

Nuclear Reactor (atomic reactor)  

Science Journals Connector (OSTI)

A nuclear reactor splits Uranium or Plutonium nuclei, and the...235 is fissionable but more than 99% of the naturally occurring Uranium is U238 that makes enrichment mandatory. In some reactors U238 and Thorium23...

2008-01-01T23:59:59.000Z

335

Investigation of cleaner technologies to minimize automotive coolant wastes  

SciTech Connect (OSTI)

The U.S. Environmental Protection Agency in cooperation with the State of New Jersey evaluated chemical filtration and distillation technologies designed to recycle automotive and heavy-duty engine coolants. These evaluations addressed the product quality, waste reduction, and economic issues. In addition, the authors examined the potential for substituting propylene glycol for ethylene glycol based engine coolant formulations. (Copyright (c) 1993 Butterworth-Heinemann Ltd.)

Randall, P.M.

1993-01-01T23:59:59.000Z

336

CFD analyses of natural circulation in the air-cooled reactor cavity cooling system  

SciTech Connect (OSTI)

The Natural Convection Shutdown Heat Removal Test Facility (NSTF) is currently being built at Argonne National Laboratory, to evaluate the feasibility of the passive Reactor Cavity Cooling System (RCCS) for Next Generation Nuclear Plant (NGNP). CFD simulations have been applied to evaluate the NSTF and NGNP RCCS designs. However, previous simulations found that convergence was very difficult to achieve in simulating the complex natural circulation. To resolve the convergence issue and increase the confidence of the CFD simulation results, additional CFD simulations were conducted using a more detailed mesh and a different solution scheme. It is found that, with the use of coupled flow and coupled energy models, the convergence can be greatly improved. Furthermore, the effects of convection in the cavity and the effects of the uncertainty in solid surface emissivity are also investigated. (authors)

Hu, R. [Nuclear Engineering Division, Argonne National Laboratory, Argonne IL (United States); Pointer, W. D. [Reactor and Nuclear Systems Division, Oak Ridge National Laboratory, Oak Ridge TN (United States)

2013-07-01T23:59:59.000Z

337

Scaling analysis for a reactor vessel mixing test  

SciTech Connect (OSTI)

The Westinghouse AP600 advanced pressurized water reactor design uses a gravity-forced safety injection system with two nozzles in the reactor vessel downcomer. In the event of a severe overcooling transient such as a steam-line break, this system delivers boron to the core to offset positive reactivity introduced by the negative moderator defect. To determine if the system design is capable of successfully terminating this type of reactivity transient, a test of the system has been initiated. The test will utilize a 1:9 scale model of the reactor vessel and cold legs. The coolant will be modeled with air, while the safety injection fluid will be simulated with a dense gas. To determine the necessary parameters for this model, a scaling analysis was performed. The continuity, diffusion, and axial Navier-Stokes equations for the injected fluid were converted into dimensionless form. A Boussinesq formulation for turbulent viscosity was applied in these equations. This procedure identified the Richardson, mixing Reynolds, diffusion Fourier, and Euler numbers as dimensionless groups of interest. Order-of-magnitude evaluation was used to determine that the Richardson and mixing Reynolds numbers were the most significant parameters to match for a similar experiment.

Radcliff, T.D.; Parsons, J.R.; Johnson, W.S. (Univ. of Tennessee, Knoxville, TN (United States)); Ekeroth, D.E. (Westinghouse Electric Corp., Pittsburgh, PA (United States))

1993-01-01T23:59:59.000Z

338

Dynamics of reverse osmosis in a standalone cogenerative nuclear reactor (Part I: reactivity changes)  

Science Journals Connector (OSTI)

The present study considers the dynamic behaviour of the pressurised water reactor safety features, represented by the integrity of the fuel cladding, under some transient cases. A cosine-shaped heating through the fuel is taken with the corresponding coolant lumps, to simulate realistic cases encountered in nuclear reactors. A mathematical model was developed for the Westinghouse 3411 MWth pressurised water reactor, as an example of a familiar design with predominantly published data design. The model consists of two parts. The first part is concerned with the dynamics of the primary side of the reactor, which is described in this paper. The second part is concerned with the secondary side of the plant, which is described elsewhere in this issue. To study the dynamics of the reactor, a model of 17 lumped parameters was used, consisting of first-order differential equations deduced from the first principles considering six groups of delayed neutrons. A computer program was developed using the Runge-Kutta method to solve these equations and to predict the behaviour of the state variables with time. Two case studies were considered as examples for normal transients. The first case study, which represents Part 1 of this study, considers the effect of primary side transient on the system as the reactivity changes. Reactor reactivity changes, including movements of the reactor control rods, which are taken as an example for the effect of the reactor primary side conditions. These reactivity changes vary from 0.0005 up to 0.003, both for positive and negative reactivity. The results of the developed model, which describe the dynamic response of the reactor primary circuit, have been analysed and verified with the relevant models. These results indicate that the reactor components and the integrity of the fuel cladding were attained during different step changes of reactivity.

Aly Karameldin; M.M. Shamloul; M.R. Shaalan; M.H. Esawy

2007-01-01T23:59:59.000Z

339

Design of Complex Systems to Achieve Passive Safety: Natural Circulation Cooling of Liquid Salt Pebble Bed Reactors  

E-Print Network [OSTI]

a tool for reactor design optimization, and for design ofdesign tool for reactor design optimization, and for designdesign tool for reactor design optimization, and for design

Scarlat, Raluca Olga

2012-01-01T23:59:59.000Z

340

Heat exchanger for reactor core and the like  

DOE Patents [OSTI]

A compact bayonet tube type heat exchanger which finds particular application as an auxiliary heat exchanger for transfer of heat from a reactor gas coolant to a secondary fluid medium. The heat exchanger is supported within a vertical cavity in a reactor vessel intersected by a reactor coolant passage at its upper end and having a reactor coolant return duct spaced below the inlet passage. The heat exchanger includes a plurality of relatively short length bayonet type heat exchange tube assemblies adapted to pass a secondary fluid medium therethrough and supported by primary and secondary tube sheets which are releasibly supported in a manner to facilitate removal and inspection of the bayonet tube assemblies from an access area below the heat exchanger. Inner and outer shrouds extend circumferentially of the tube assemblies and cause the reactor coolant to flow downwardly internally of the shrouds over the tube bundle and exit through the lower end of the inner shroud for passage to the return duct in the reactor vessel.

Kaufman, Jay S. (Del Mar, CA); Kissinger, John A. (Del Mar, CA)

1986-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

High-value use of weapons-plutonium by burning in molten salt accelerator-driven subcritical systems or reactors  

SciTech Connect (OSTI)

The application of thermal-spectrum molten-salt reactors and accelerator-driven subcritical systems to the destruction of weapons-return plutonium is considered from the perspective of deriving the maximum societal benefit. The enhancement of electric power production from burning the fertile fuel {sup 232}Th with the plutonium is evaluated. Also the enhancement of destruction of the accumulated waste from commercial nuclear reactors is considered using the neutron-rich weapons plutonium. Most cases examined include the concurrent transmutation of the long-lived actinide and fission product waste ({sup 99}Tc, {sup 129}I, {sup 135}Cs, {sup 126}Sn and {sup 79}Se).

Bowman, C.D.; Venneri, F.

1993-11-01T23:59:59.000Z

342

The Mass Tracking System for the Integral Fast Reactor fuel cycle  

SciTech Connect (OSTI)

As part of the Fuel Cycle Facility (FCF) of Argonne National Laboratory`s Integral Fast Reactor (IFR) demonstration, a computer-based Mass-Tracking (MTG) System has been developed. The MTG System collects, stores, retrieves and processes data on all operations which directly affect the flow of process material through FCF and supports such activities as process modeling, compliance with operating limits (e.g., criticality safety), material control and accountability and operational information services. Its architecture is client/server, with input and output connections to operator`s equipment-control stations on the floor of FCF as well as to terminal sessions. Its heterogeneous database includes a relational-database manager as well as both binary and ASCII data files. The design of the database, and the software that supports it, is based on a model of discrete accountable items distributed in space and time and constitutes a complete historical record of the material processed in FCF. Although still under development, much of the MTG System has been qualified and is in production use.

Adams, C.H.; Beitel, J.C.; Birgersson, G.; Bucher, R.G.; Carrico, C.B.; Daly, T.A. [Argonne National Lab., IL (United States); Keyes, R.W. [Argonne National Lab., Idaho Falls, ID (United States)

1994-07-01T23:59:59.000Z

343

Experimental Breeder Reactor-II Primary Tank System Wash Water Workshop  

Broader source: Energy.gov [DOE]

In 1994 Congress ordered the shutdown of the Experimental Breeder Reactor-II (EBR-II) and a closure project was initiated.

344

The development of a remote monitoring system for the Nuclear Science Center reactor.  

E-Print Network [OSTI]

??With funding provided by Nuclear Energy Research Initiative (NERI), design of Secure, Transportable, Autonomous Reactors (STAR) to aid countries with insufficient energy supplies is underway.… (more)

Jiltchenkov, Dmitri Victorovich

2012-01-01T23:59:59.000Z

345

Influence of engine coolant composition on the electrochemical degradation behavior of EPDM radiator hoses  

SciTech Connect (OSTI)

EPDM (ethylene-propylene rubber) has been used for more than 25 years as the main elastomer in radiator hoses because it offers a well-balanced price/performance ratio in this field of application. Some years ago the automotive and rubber industry became aware of a problem called electrochemical degradation and cracking. Cooling systems broke down due to a typical cracking failure of some radiator hoses. Different test methods were developed to simulate and solve the problem on laboratory scale. The influence of different variables with respect to the electrochemical degradation and cracking. Cooling systems broke down due to a typical cracking failure of some radiator hoses. Different test methods were developed to simulate and solve the problem on laboratory scale. The influence of different variables with respect to the electrochemical degradation process has been investigated, but until recently the influence of the engine coolant was ignored. Using a test method developed by DSM elastomers, the influence of the composition of the engine coolant as well as of the EPDM composition has now been evaluated. This paper gives an overview of test results with different coolant technologies and offers a plausible explanation of the degradation mechanisms as a function of the elastomer composition.

Vroomen, G.L.M. [DSM Elastomers Europe, Geleen (Netherlands). Application Center of Expertise; Lievens, S.S.; Maes, J.P. [Texaco Technology Ghent (Belgium)

1999-08-01T23:59:59.000Z

346

Fast spectrum space reactor sizing code for calandria-type cores (CORSCO Code). [Li  

SciTech Connect (OSTI)

The CORSCO code rapidly sizes reactor cores that have calandria-type geometry. The fuel configuration modeled is a large ceramic zone that contains numerous small cylindrical coolant channels spaced apart with a triangular pitch. A minimum reactor weight is obtained for a fixed set of constraints (peak fuel temperature, peak coolant velocity, etc.) by obtaining a unique solution to a set of five thermal/hydraulic equations, as well as a required excess reactivity which is specified by a core size dependent one-group criticality expression. Typical results are shown for a W-Re/UN cermet-fueled, lithium-cooled space reactor over a power range of 25 to 100 MWt. Reactor sensitivity coefficients are also shown for changes in reactor weight and number of coolant channels due to changes in core thermal/hydraulic constraints.

Specht, E.R.; Villalobos, A. (Rockwell International, Rocketdyne Division, 6633 Canoga Avenue, HB23, Canoga Park, California (USA))

1991-01-10T23:59:59.000Z

347

Effect of Lithium Enrichment on the Tritium Breeding Characteristics of Various Breeders in a Fusion Driven Hybrid Reactor  

Science Journals Connector (OSTI)

Selection of lithium containing materials is very important in the design of a deuterium–tritium (DT) fusion driven hybrid reactor in order to supply its tritium self- ... lithium-6 enrichment in the coolant of t...

Mustafa Übeyli

2009-09-01T23:59:59.000Z

348

Numerical solution for stochastic point-kinetics equations with sinusoidal reactivity in dynamical system of nuclear reactor  

Science Journals Connector (OSTI)

In this present analysis, the numerical simulation methods are applied to calculate the solution for stochastic point-kinetic equations with sinusoidal reactivity in dynamical system of nuclear reactor. The resulting system of differential equations is solved for each time step-size. Using experimental data, the methods are investigated over initial conditions and with sinusoidal reactivity. The computational results designate that these numerical approximation methods are straightforward, effective and easy for solving stochastic point-kinetic equations.

S. Saha Ray; A. Patra

2013-01-01T23:59:59.000Z

349

LIGHT WATER REACTOR SUSTAINABILITY PROGRAM ADVANCED INSTRUMENTATION, INFORMATION, AND CONTROL SYSTEMS TECHNOLOGIES TECHNICAL PROGRAM PLAN FOR 2013  

SciTech Connect (OSTI)

Reliable instrumentation, information, and control (II&C) systems technologies are essential to ensuring safe and efficient operation of the U.S. light water reactor (LWR) fleet. These technologies affect every aspect of nuclear power plant (NPP) and balance-of-plant operations. In 1997, the National Research Council conducted a study concerning the challenges involved in modernization of digital instrumentation and control systems in NPPs. Their findings identified the need for new II&C technology integration.

Bruce Hallbert; Ken Thomas

2014-07-01T23:59:59.000Z

350

Cryogenic system component development for the fusion experimental reactor at JAERI  

SciTech Connect (OSTI)

The major objective of fusion R and D at the Japan Atomic Energy Research Institute (JAERI) is to construct the Fusion Experimental Reactor (FER) to follow JT-60. The construction of FER inevitably requires development of a large, reliable, and efficient helium liquefier/refrigerator and the more advanced cryogenic technology for cooling superconducting toroidal and poloidal coils. Typical characteristics required for the cryogenic system of FER are 10 to 20 kW at 4 K as one unit, reliability for > 8000 h, a stable pulsed heat load, and high-energy efficiency of > 1/500. In this cryogenic system, the major components such as the helium compressor, turbo-expander, cold circulation pump for supercritical helium, and cold compressor to reduce operating temperature below 4 K should be scaled up to a mass flow rate of > 1000 g/s. For this purpose, JAERI has developed cryogenics since 1980 in accordance with the development program in which the scaling up of the major components mentioned above are involved as well as cooling technology development.

Kato, T.; Kamiya, S.; Tada, E.; Hiyama, T.; Kawano, K.; Shimamoto, S.

1986-01-01T23:59:59.000Z

351

The Advanced Candu reactor annunciation system - Compliance with IEC standard and US NRC guidelines  

SciTech Connect (OSTI)

Annunciation is a key plant information system that alerts Operations staff to important changes in plant processes and systems. Operational experience at nuclear stations worldwide has shown that many annunciation implementations do not provide the support needed by Operations staff in all plant situations. To address utility needs for annunciation improvement in Candu plants, AECL in partnership with Canadian Candu utilities, undertook an annunciation improvement program in the early nineties. The outcome of the research and engineering development program was the development and simulator validation of alarm processing, display, and information presentation techniques that provide practical and effective solutions to key operational deficiencies with earlier annunciation implementations. The improved annunciation capabilities consist of a series of detection, information processing and presentation functions called the Candu Annunciation Message List System (CAMLS). The CAMLS concepts embody alarm processing, presentation and interaction techniques, and strategies and methods for annunciation system configuration to ensure improved annunciation support for all plant situations, especially in upset situations where the alarm generation rate is high. The Advanced Candu Reactor (ACR) project will employ the CAMLS annunciation concepts as the basis for primary annunciation implementations. The primary annunciation systems will be implemented from CAMLS applications hosted on AECL Advanced Control Centre Information System (ACCIS) computing technology. The ACR project has also chosen to implement main control room annunciation aspects in conformance with the following international standard and regulatory review guide for control room annunciation practice: International Electrotechnical Commission (IEC) 62241 - Main Control Room, Alarm Function and Presentation (International standard) US NRC NUREG-0700 - Human-System Interface Design Review Guidelines, Section 4 - Alarm System (Regulatory review guide) In order for the ACR annunciation system to comply with IEC-62241 and NUREG-0700, the CAMLS concepts must satisfy their respective requirements and guidelines. This paper will provide a summary of how CAMLS complies with IEC-62241 and NUREG-0700. Overall, the CAMLS-based annunciation requirements conform to the intent of the recommended annunciation practices included in both these documents. However, there are minor differences in requirements interpretation and annunciation practice between CAMLS implementation concepts and the recommended practice in each document. Generally the differences with IEC-62241 revolve around definitions, the display properties of new alarms, and video display unit (VDU) alarm display organization. The differences with NUREG-0700 revolve around segregation of status alarms, the use of spatially dedicated, continuously visible displays, simultaneous display of high-priority alarms, audible signals for alarm states and reminder signals, blank lines in alarm message lists and manual silencing. These minor differences are discussed and rationales for the CAMLS implementation concepts are provided. (authors)

Leger, R.; Malcolm, S. [Atomic Energy of Canada Limited, 2251 Speakman Drive, Mississauga, Ont. L5K 1B2 (Canada); Davey, E. [Crew Systems Solutions, Deep River, Ont. K0J 1P0 (Canada)

2006-07-01T23:59:59.000Z

352

Burst criterion of Zircaloy fuel claddings in a loss-of-coolant accident  

SciTech Connect (OSTI)

A burst criterion mode developed for Zircaloy claddings of a pressurized water reactor in a loss-of-coolant accident assumes that the time of burst is reached when the local stress equals the limiting burst stress. The burst stress is assumed to depend on the temperature and oxygen concentration of the Zircaloy. With the histories of temperature and pressure known, the strain, stress, and oxygen content can be calculated by integration of the creep equation and correlation of the oxidation kinetics. Once the time of burst has been calculated, all burst data, that is, strain, stress, temperature, pressure, and oxygen content, are determined. The burst temperatures and burst strains predicted by the model are in good agreement with the test data. 7 refs.

Erbacher, F.J.; Neitzel, H.J.; Rosinger, H.; Schmidt, H.; Wiehr, K.

1982-01-01T23:59:59.000Z

353

Reactor operation safety information document  

SciTech Connect (OSTI)

The report contains a reactor facility description which includes K, P, and L reactor sites, structures, operating systems, engineered safety systems, support systems, and process and effluent monitoring systems; an accident analysis section which includes cooling system anomalies, radioactive materials releases, and anticipated transients without scram; a summary of onsite doses from design basis accidents; severe accident analysis (reactor core disruption); a description of operating contractor organization and emergency planning; and a summary of reactor safety evolution. (MB)

Not Available

1990-01-01T23:59:59.000Z

354

NAPTH: Neutronics analysis code system for the fusion–fission hybrid reactor with pressure tube type blanket  

Science Journals Connector (OSTI)

The fusion–fission hybrid reactor is considered as a potential path to the early application of fusion energy. A new concept with pressure tube type blanket has recently been proposed for a feasible hybrid reactor. In this paper, a code system for the neutronics analysis of the pressure tube type hybrid reactor is developed based on the two-step calculation scheme: the few-group homogeneous constant calculation and the full blanket calculation. The few-group homogeneous constants are calculated using the lattice code DRAGON4. The blanket transport calculation is performed by the multigroup Monte Carlo code. A link procedure for fitting the cross sections is developed between these two steps. An additional procedure is developed to calculate the burnup, power distribution, energy multiplication factor, tritium breeding ratio and neutron multiplication factor. From some numerical results, it is found that the code system NAPTH is reliable and exhibits good calculation efficiency. It can be used for the conceptual design of the pressure tube type hybrid reactor with precise geometry.

Tiejun Zu; Hongchun Wu; Youqi Zheng; Liangzhi Cao; Chao Yang

2013-01-01T23:59:59.000Z

355

Simulation of condensation systems in the presence of noncondensable gases  

E-Print Network [OSTI]

Transient 53 26 Core Liquid Temperature 56 27 Pressure in Hot Leg 57 28 Pressure in Core 58 29 Downcomer Liquid Tempera, ture 30 Reactor Vessel Upperhead Gas Temperature . 60 31 Gas Void Fraction in the Hot Leg 62 32 Gas Void Fractions in the Cold Leg... of the postulated containment cooling system for advanced reactors. Steam is produced in an airtight vessel in which air is present. The steam in the steam-air mixture is allowed to condense on the surface of s. copper cylinder through which coolant is passed...

Raja, Laxminarayan Lakshmana

2012-06-07T23:59:59.000Z

356

Baseline risk assessment of the perched water system at the INEL test reactor area  

SciTech Connect (OSTI)

A baseline health risk assessment (HRA) was prepared to evaluate potential risks to human health and the environment posed by the Perched Water System (PWS) at the Test Reactor Area (TRA). The PWS has been designated Operable Unit 2-12, one of the 13 operable units identified at TRA. During the period from 1962 to 1990, a total of 6770 million gal of water were discharged from the TRA to unlined surface ponds. Wastewater discharged to the surface ponds at TRA percolates downward through the surficial alluvium and the underlying basalt bedrock. A resulting shallow perched water zone has formed at the interface between the surficial sediments and the underlying basalt. Further downward movement of groundwater is again impeded by a low-permeability layer of silt, clay, and sand encountered at a depth of [approximately]150 ft. The deep perched water zone occurs on top of this low-permeability interbed. An evaluation was made as to whether potential risks for the PWS could justify implementing a remedial action. The risk evaluation consisted of two parts, the human health evaluation and the ecological evaluation.

Gordon, J.W.; Sinton, P.O. (Dames Moore, Denver, CO (United States)); Jensen, N. (DOE, Idaho Falls, ID (United States)); McCormick, S. (Idaho National Engineering Lab., Idaho Falls, ID (United States))

1993-01-01T23:59:59.000Z

357

Safety Design Strategy for the Advanced Test Reactor Emergency Firewater Injection System Replacement Project  

SciTech Connect (OSTI)

In accordance with the requirements of U.S. Department of Energy (DOE) Order 413.3B, “Program and Project Management for the Acquisition of Capital Assets,” safety must be integrated into the design process for new or major modifications to DOE Hazard Category 1, 2, and 3 nuclear facilities. The intended purpose of this requirement involves the handling of hazardous materials, both radiological and chemical, in a way that provides adequate protection to the public, workers, and the environment. Requirements provided in DOE Order 413.3B and DOE Order 420.1B, “Facility Safety,” and the expectations of DOE-STD-1189-2008, “Integration of Safety into the Design Process,” provide for identification of hazards early in the project and use of an integrated team approach to design safety into the facility. This safety design strategy provides the basic safety-in-design principles and concepts that will be used for the Advanced Test Reactor Reliability Sustainment Project. While this project does not introduce new hazards to the ATR, it has the potential for significant impacts to safety-related systems, structures, and components that are credited in the ATR safety basis and are being replaced. Thus the project has been determined to meet the definition of a major modification and is being managed accordingly.

Noel Duckwitz

2011-06-01T23:59:59.000Z

358

UCLA program in reactor studies: The ARIES tokamak reactor study  

SciTech Connect (OSTI)

The ARIES research program is a multi-institutional effort to develop several visions of tokamak reactors with enhanced economic, safety, and environmental features. The aims are to determine the potential economics, safety, and environmental features of a range of possible tokamak reactors, and to identify physics and technology areas with the highest leverage for achieving the best tokamak reactor. Four ARIES visions are currently planned for the ARIES program. The ARIES-1 design is a DT-burning reactor based on modest'' extrapolations from the present tokamak physics database and relies on either existing technology or technology for which trends are already in place, often in programs outside fusion. ARIES-2 and ARIES-4 are DT-burning reactors which will employ potential advances in physics. The ARIES-2 and ARIES-4 designs employ the same plasma core but have two distinct fusion power core designs; ARIES-2 utilize the lithium as the coolant and breeder and vanadium alloys as the structural material while ARIES-4 utilizes helium is the coolant, solid tritium breeders, and SiC composite as the structural material. Lastly, the ARIES-3 is a conceptual D-{sup 3}He reactor. During the period Dec. 1, 1990 to Nov. 31, 1991, most of the ARIES activity has been directed toward completing the technical work for the ARIES-3 design and documenting the results and findings. We have also completed the documentation for the ARIES-1 design and presented the results in various meetings and conferences. During the last quarter, we have initiated the scoping phase for ARIES-2 and ARIES-4 designs.

Not Available

1991-01-01T23:59:59.000Z

359

Evaluation of in-vessel corium retention through external reactor vessel cooling for integral reactor  

SciTech Connect (OSTI)

In-vessel corium retention through external reactor vessel cooling (IVR-ERVC) for a small integral reactor has been evaluated to determine the thermal margin for the prevention of a reactor vessel failure. A thermal load analysis from the corium pool to the outer reactor vessel wall in the lower plenum of the reactor vessel has been performed to determine the heat flux distribution. The critical heat flux (CHF) on the outer reactor vessel wall has been determined to fix the maximum heat removal rate through the external coolant between the outer reactor vessel and the insulation of the reactor vessel. Finally, the thermal margin has been evaluated by comparison of the thermal load with the maximum heat removal rate of the CHF on the outer reactor vessel wall. The maximum heat flux from the corium pool to the outer reactor vessel is estimated at approximately 0.25 MW/m{sup 2} in the metallic layer because of the focusing effect. The CHF of the outer reactor vessel is approximately 1.1 MW/m{sup 2} because of a two phase natural circulation mass flow. Since the thermal margin for the IVR-ERVC is sufficient, the reactor vessel integrity is maintained during a severe accident of a small integral reactor. (authors)

Park, R. J.; Lee, J. R.; Kim, S. B.; Jin, Y.; Kim, H. Y. [Korea Atomic Energy Research Inst., 1045 Daedeok-daero, Yuseong-gu, Daejeon, 305-353 (Korea, Republic of)

2012-07-01T23:59:59.000Z

360

Oxygen transport membrane system and method for transferring heat to catalytic/process reactors  

DOE Patents [OSTI]

A method and apparatus for producing heat used in a synthesis gas production is provided. The disclosed method and apparatus include a plurality of tubular oxygen transport membrane elements adapted to separate oxygen from an oxygen containing stream contacting the retentate side of the membrane elements. The permeated oxygen is combusted with a hydrogen containing synthesis gas stream contacting the permeate side of the tubular oxygen transport membrane elements thereby generating a reaction product stream and radiant heat. The present method and apparatus also includes at least one catalytic reactor containing a catalyst to promote the stream reforming reaction wherein the catalytic reactor is surrounded by the plurality of tubular oxygen transport membrane elements. The view factor between the catalytic reactor and the plurality of tubular oxygen transport membrane elements radiating heat to the catalytic reactor is greater than or equal to 0.5.

Kelly, Sean M; Kromer, Brian R; Litwin, Michael M; Rosen, Lee J; Christie, Gervase Maxwell; Wilson, Jamie R; Kosowski, Lawrence W; Robinson, Charles

2014-01-07T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

IoT-Based Maintenance Process Design for Fusion Reactor Remote Handling System  

Science Journals Connector (OSTI)

Nuclear fusion is one of the most important ways ... to risk of ionizing radiation, the nuclear fusion reactor will relay on remote handling maintenance to ... the maintenance efficiency. The basic structure of fusion

Ruonan Zhang; Xinbao Liu

2014-12-01T23:59:59.000Z

362

Mechanical Strength, Swelling and Weight Loss of Inorganic Fusion Magnet Insulation Systems Following Reactor Irradiation  

Science Journals Connector (OSTI)

Superconducting fusion magnets require a high electrical and mechanical ... were irradiated at ambient temperature in the TRIGA reactor (Vienna, Austria) up to neutron fluences...21, 1022 and 5x1022 m?2...(E>0.1 ...

K. Humer; P. Rosenkranz; H. W. Weber…

2000-01-01T23:59:59.000Z

363

Maximum Fuel Utilization in Advanced Fast Reactors without Actinides Separation  

E-Print Network [OSTI]

Physics Optimization of Breed and Burn Fast Reactor Systems.reactors: Fabrication and properties and their optimization.

Heidet, Florent

2010-01-01T23:59:59.000Z

364

Synthesis and modeling of the H?-system of magnetic control of the plasma in the tokamak-reactor  

Science Journals Connector (OSTI)

The article deals with the development of a two-contour system of magnetic control of the position, current, and shape of the plasma in the tokamak-reactor. The H?-theory of control is used for the synthesis of a scalar and ... Keywords: 28.52.-s, 52.55.-s, 52.55.Fa, 52.65.-y, 52.65.Kj

V. N. Dokuka; A. V. Kadurin; Yu. V. Mitrishkin; R. R. Khayrutdinov

2007-08-01T23:59:59.000Z

365

Uncertainty evaluation of reliability of safety grade decay heat removal system of Indian prototype fast breeder reactor  

Science Journals Connector (OSTI)

Abstract Deterministic and probabilistic safety assessment of nuclear power reactor technology is very important in assuring that the design is robust and safety systems perform as per requirement. The parameters required as input data for such analysis have uncertainties associated with them. Their impact is to be assessed on the results obtained for such analyses and it affects the overall decision making process. Safety Grade Decay Heat Removal System (SGDHRS) is one of the safety systems in fast breeder reactors and itremoves decay heat after reactor shutdown. It is a critical safety system; hence failure frequency for SGDHR is targeted to be less than 1.0 × 10?7 per reactor year. By bringing diversity in some of the components of SGDHRS, such as sodium-to-sodium decay heat exchanger (DHX), sodium to air heat exchanger (AHX) and valves, one can achieve the targeted low failure frequency of SGDHRS. We perform uncertainty analysis of the reliability of such SGDHRS here. Uncertainty in failure rate (of components of SGDHRS) is assumed to follow the log-normal distribution with error factor of three. Monte Carlo method of sampling is used in MATLAB environment. Results are obtained in terms of mean, median and standard deviation values of failure frequency. Percentile and confidence interval analysis of mean values are also obtained. These provide 95 and 98 percentile and confidence interval values of 98%, 99% and 99.8%. It is found that error factor of failure frequency of SGDHRS is found to be less than 3 in all the cases except the one in which DHX, AHX and Valves are designed with diversity in design. It is to be noted here that error factor of all input parameters distribution is taken as 3.

H.L. Kumawat; Om Pal Singh; Prabhat Munshi

2013-01-01T23:59:59.000Z

366

An experimental system for the n-butyl-lithium initiated polymerization of styrene in a multi-sampled batch reactor  

E-Print Network [OSTI]

. The power to the water heater is controlled by a Fisher Proportional Temperature Control (Catalog P3 TENPERATURE CONTROLLER CONSTANT TENPERATURE BATH P2 CHILLER ELECTRICAL HEATER Figure 3. Schematic of Reactor Temperature Control System 20... successful column; i, e, , extremely high pressure drops and low plate counts were observed in these columns. As a last measure, the gel was stirred in a hot, concen- trated sodium hydroxide solution (approximately pH 13) for ten hours. The excess sodium...

Cox, James Harvey

2012-06-07T23:59:59.000Z

367

Design and development of a special purpose SAFT system for nondestructive evaluation of nuclear reactor vessels and piping components  

SciTech Connect (OSTI)

This report describes the design details of a special purpose system for real-time nondestructive evaluation of reactor vessels and piping components. The system consists of several components and the report presents the results of the research aimed at the design of each component and recommendations based on the results. One major component of the NDE system, namely the real-time SAFT processor, was designed with sufficient details to enable the fabrications of a prototype by GARD Inc. under a subcontract from The University of Michigan and the report includes their results and conclusions.

Ganapathy, S.; Schmult, B.; Wu, W.S.; Dennehy, T.G.; Moayeri, N.; Kelly, P.

1985-08-01T23:59:59.000Z

368

Directly connected heat exchanger tube section and coolant-cooled structure  

DOE Patents [OSTI]

A cooling apparatus for an electronics rack is provided which includes an air-to-liquid heat exchanger, one or more coolant-cooled structures and a tube. The heat exchanger, which is associated with the electronics rack and disposed to cool air passing through the rack, includes a plurality of distinct, coolant-carrying tube sections, each tube section having a coolant inlet and a coolant outlet, one of which is coupled in fluid communication with a coolant loop to facilitate flow of coolant through the tube section. The coolant-cooled structure(s) is in thermal contact with an electronic component(s) of the rack, and facilitates transfer of heat from the component(s) to the coolant. The tube connects in fluid communication one coolant-cooled structure and the other of the coolant inlet or outlet of the one tube section, and facilitates flow of coolant directly between that coolant-carrying tube section of the heat exchanger and the coolant-cooled structure.

Chainer, Timothy J; Coico, Patrick A; Graybill, David P; Iyengar, Madhusudan K; Kamath, Vinod; Kochuparambil, Bejoy J; Schmidt, Roger R; Steinke, Mark E

2014-04-01T23:59:59.000Z

369

Operational control of boiling water reactor stability  

SciTech Connect (OSTI)

Boiling water reactor cores are susceptible to instabilities, which generate power oscillations. Specific reactor operating practices can provide a mechanism for control of the instability phenomenon. An axial separation of the core into a single-phase region and a two-phase region resolves the influence of axial flux shapes on core stability. This separation provides the means to derive a core stability control that ensures significant reactor stability margin. The control is achieved by maintaining the core average bulk coolant saturation elevation above a predetermined axial plane. The control can be reliably and efficiently implemented during reactor operations. Analysis demonstrates that variations in parameters important to stability have only secondary influences on stability margin when the control is in effect. Actual plant experience with a large commercial boiling water reactor confirms the capabilities of this stability control in an operational setting.

Mowry, C.M. [PECO Energy, Wayne, PA (United States); Nir, I. [Entergy Operations, Jackson, MS (United States); Newkirk, D.W. [GE Nuclear Energy, San Jose, CA (United States)

1995-03-01T23:59:59.000Z

370

Conceptual design study on very small long-life gas cooled fast reactor using metallic natural Uranium-Zr as fuel cycle input  

SciTech Connect (OSTI)

A conceptual design study of very small 350 MWth Gas-cooled Fast Reactors with Helium coolant has been performed. In this study Modified CANDLE burn-up scheme was implemented to create small and long life fast reactors with natural Uranium as fuel cycle input. Such system can utilize natural Uranium resources efficiently without the necessity of enrichment plant or reprocessing plant. The core with metallic fuel based was subdivided into 10 regions with the same volume. The fresh Natural Uranium is initially put in region-1, after one cycle of 10 years of burn-up it is shifted to region-2 and the each region-1 is filled by fresh Natural Uranium fuel. This concept is basically applied to all axial regions. The reactor discharge burn-up is 31.8% HM. From the neutronic point of view, this design is in compliance with good performance.

Monado, Fiber, E-mail: fiber.monado@gmail.com [Nuclear Physics and Biophysics Research Group, Dept. of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Bandung, Indonesia and Dept. of Physics, Faculty of Mathematics and Natural Sciences, Sriwijaya University (Indonesia); Ariani, Menik [Dept. of Physics, Faculty of Mathematics and Natural Sciences, Sriwijaya University (Indonesia); Su'ud, Zaki; Waris, Abdul; Basar, Khairul; Permana, Sidik [Nuclear Physics and Biophysics Research Group, Dept. of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Bandung (Indonesia); Aziz, Ferhat [National Nuclear Energy Agency of Indonesia (BATAN) (Indonesia); Sekimoto, Hiroshi [CRINES, Tokyo Institute of Technology, O-okoyama, Meguro-ku, Tokyo 152-8550 (Japan)

2014-02-12T23:59:59.000Z

371

Nuclear reactor construction with bottom supported reactor vessel  

DOE Patents [OSTI]

An improved liquid metal nuclear reactor construction has a reactor core and a generally cylindrical reactor vessel for holding a large pool of low pressure liquid metal coolant and housing the core within the pool. The reactor vessel has an open top end, a closed flat bottom end wall and a continuous cylindrical closed side wall interconnecting the top end and bottom end wall. The reactor also has a generally cylindrical concrete containment structure surrounding the reactor vessel and being formed by a cylindrical side wall spaced outwardly from the reactor vessel side wall and a flat base mat spaced below the reactor vessel bottom end wall. A central support pedestal is anchored to the containment structure base mat and extends upwardly therefrom to the reactor vessel and upwardly therefrom to the reactor core so as to support the bottom end wall of the reactor vessel and the lower end of the reactor core in spaced apart relationship above the containment structure base mat. Also, an annular reinforced support structure is disposed in the reactor vessel on the bottom end wall thereof and extends about the lower end of the core so as to support the periphery thereof. In addition, an annular support ring having a plurality of inward radially extending linear members is disposed between the containment structure base mat and the bottom end of the reactor vessel wall and is connected to and supports the reactor vessel at its bottom end on the containment structure base mat so as to allow the reactor vessel to expand radially but substantially prevent any lateral motions that might be imposed by the occurrence of a seismic event. The reactor construction also includes a bed of insulating material in sand-like granular form, preferably being high density magnesium oxide particles, disposed between the containment structure base mat and the bottom end wall of the reactor vessel and uniformly supporting the reactor vessel at its bottom end wall on the containment structure base mat so as to insulate the reactor vessel bottom end wall from the containment structure base mat and allow the reactor vessel bottom end wall to freely expand as it heats up while providing continuous support thereof. Further, a deck is supported upon the side wall of the containment structure above the top open end of the reactor vessel, and a plurality of serially connected extendible and retractable annular bellows extend between the deck and the top open end of the reactor vessel and flexibly and sealably interconnect the reactor vessel at its top end to the deck. An annular guide ring is disposed on the containment structure and extends between its side wall and the top open end of the reactor vessel for providing lateral support of the reactor vessel top open end by limiting imposition of lateral loads on the annular bellows by the occurrence of a lateral seismic event.

Sharbaugh, John E. (Bullskin Township, Fayette County, PA)

1987-01-01T23:59:59.000Z

372

Assessment of passive safety system performance under main steam line break accident  

Science Journals Connector (OSTI)

Abstract A generation III + Boiling Water Reactor (BWR) which relies on natural circulation has evolved from earlier BWR designs by incorporating passive safety features which require no emergency injection pump and no operator action or Alternating Current (AC) power supply. The generation III + BWR’s passive safety systems include the Automatic Depressurization System (ADS), the Suppression Pool (SP), the Standby Liquid Control System (SLCS), the Gravity Driven Cooling System (GDCS), the Isolation Condenser System (ICS), and the Passive Containment Cooling System (PCCS). The ADS is actuated to rapidly depressurize the reactor leading to the GDCS injection. The large amount of water in the SP condenses steam from the reactor. The SLCS provides makeup water to the reactor. The GDCS injects water into the reactor by gravity head and provides cooling to the core. The ICS and the PCCS are used to remove the decay heat from the reactor. The objective of this paper is to analyze the response of passive safety systems under the Loss of Coolant Accident (LOCA). A Main Steam Line Break (MSLB) test has been conducted in the Purdue University Multi-Dimensional Integral Test Assembly (PUMA) which is scaled to represent the generation III + BWR. The main results of PUMA MSLB test were that the reactor coolant level was well above the Top of Active Fuel (TAF) and the reactor containment pressure has remained below the design pressure. In particular, the minimum water level (1.706 m) was 5% higher than the TAF (1.623 m) and the containment maximum pressure (271 kPa) was 35% lower than the safety limit (414 kPa), respectively.

J. Lim; S.W. Choi; J. Yang; D.Y. Lee; S. Rassame; T. Hibiki; M. Ishii

2014-01-01T23:59:59.000Z

373

Nuclear reactor flow control method and apparatus  

DOE Patents [OSTI]

Method and apparatus for improving coolant flow in a nuclear reactor during accident as well as nominal conditions. The reactor has a plurality of fuel elements in sleeves and a plenum above the fuel and through which the sleeves penetrate. Holes are provided in the sleeve so that coolant from the plenum can enter the sleeve and cool the fuel. The number and size of the holes are varied from sleeve to sleeve with the number and size of holes being greater for sleeves toward the center of the core and less for sleeves toward the periphery of the core. Preferably the holes are all the same diameter and arranged in rows and columns, the rows starting from the bottom of every sleeve and fewer rows in peripheral sleeves and more rows in the central sleeves.

Church, John P. (1204 Woodbine Rd., Aiken, SC 29803)

1993-01-01T23:59:59.000Z

374

Technology Development Program for an Advanced Potassium Rankine Power Conversion System Compatible with Several Space Reactor Designs  

SciTech Connect (OSTI)

This report documents the work performed during the first phase of the National Aeronautics and Space Administration (NASA), National Research Announcement (NRA) Technology Development Program for an Advanced Potassium Rankine Power Conversion System Compatible with Several Space Reactor Designs. The document includes an optimization of both 100-kW{sub e} and 250-kW{sub e} (at the propulsion unit) Rankine cycle power conversion systems. In order to perform the mass optimization of these systems, several parametric evaluations of different design options were investigated. These options included feed and reheat, vapor superheat levels entering the turbine, three different material types, and multiple heat rejection system designs. The overall masses of these Nb-1%Zr systems are approximately 3100 kg and 6300 kg for the 100- kW{sub e} and 250-kW{sub e} systems, respectively, each with two totally redundant power conversion units, including the mass of the single reactor and shield. Initial conceptual designs for each of the components were developed in order to estimate component masses. In addition, an overall system concept was presented that was designed to fit within the launch envelope of a heavy lift vehicle. A technology development plan is presented in the report that describes the major efforts that are required to reach a technology readiness level of 6. A 10-year development plan was proposed.

Yoder, G.L.

2005-10-03T23:59:59.000Z

375

Measurement of the lifetime of prompt neutrons in the system BARS-6 reactor—Laser unit by the statistical frequency method  

Science Journals Connector (OSTI)

Experiments measuring the lifetime of prompt neutrons in the system BARS-6 reactor—laser unit by the statistical frequency method are described. A theoretical substantiation of the method employed is given on ...

S. A. Morozov; S. N. Kovtun; L. I. Prokhorova; P. S. Shutov; S. S. Shutov

1999-11-01T23:59:59.000Z

376

Materials Test-2 LOCA Simulation in the NRU Reactor  

SciTech Connect (OSTI)

A simulated loss-of-coolant accident was performed with a full-length test bundle of pressurized water reactor fuel rods. This third experiment of the program produced fuel cladding temperatures exceeding 1033 K (1400°F) for 155 s and resulted in eight ruptured fuel rods. Experiment data and initial results are presented in the form of photographs and graphical summaries.

Barner, J. O.; Hesson, G. M.; King, I. L.; Marshall, R. K.; Parchen, L. J.; Pilger, J. P.; Rausch, W. N.; Russcher, G. E.; Webb, B. J.; Wildung, N. J.; Wilson, C. L.; Wismer, M. D.; Mohr, C. L.

1982-03-01T23:59:59.000Z

377

Modular Inspection System for a Complete IN-Service Examination of Nuclear Reactor Pressure Vessel, Including Beltline Region  

SciTech Connect (OSTI)

Final Report for a DOE Phase II Contract Describing the design and fabrication of a reactor inspection modular rover prototype for reactor vessel inspection.

David H. Bothell

2000-04-30T23:59:59.000Z

378

Monitoring system for a liquid-cooled nuclear fission reactor. [PWR  

DOE Patents [OSTI]

The invention provides improved means for detecting the water levels in various regions of a water-cooled nuclear power reactor, viz., in the downcomer, in the core, in the inlet and outlet plenums, at the head, and elsewhere; and also for detecting the density of the water in these regions. The invention utilizes a plurality of exterior gamma radiation detectors and a collimator technique operable to sense separate regions of the reactor vessel to give respectively, unique signals for these regions, whereby comparative analysis of these signals can be used to advise of the presence and density of cooling water in the vessel.

DeVolpi, A.

1984-07-20T23:59:59.000Z

379

Performance of commercial off-the-shelf microelectromechanical systems sensors in a pulsed reactor environment  

SciTech Connect (OSTI)

Prompted by the unexpected failure of piezoresistive sensors in both an elevated gamma-ray environment and reactor core pulse tests, we initiated radiation testing of several MEMS piezoresistive accelerometers and pressure transducers to ascertain their radiation hardness. Some commercial off-the-shelf sensors are found to be viable options for use in a high-energy pulsed reactor, but others suffer severe degradation and even catastrophic failure. Although researchers are promoting the use of MEMS devices in radiation-harsh environment, we nevertheless find assurance testing necessary.

Hobert, Keith Wdwin [Los Alamos National Laboratory; Heger, Arlen S [Los Alamos National Laboratory; Mc Cready, Steven S [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

380

Power Reactor Progress  

Science Journals Connector (OSTI)

Argonne kicks off EBWR; Allis-Chalmers plans power reactor using both nuclear and conventional fuels ... NUCLEAR POWER took two giant steps last week. ... Just as the first nuclear power system in the U. S. designed and built solely for the generation of electric power went into full operation at Argonne, Allis-Chalmers came up with a new twist in power reactors—a controlled recirculation boiling reactor (CRBR) using both nuclear and conventional fuels (C&EN, Feb. 18, page 7). ...

1957-02-25T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Radiation safety assessment of a system of small reactors for distributed energy  

Science Journals Connector (OSTI)

......inventory (t) 19.8 Fuel Outer diameterpitch...in UO2 No. of fuel assembles 69 Control...3014.0 Reactor vessel Inner diameterheight...of the energy consumption area, aiming...For design of a fuel exchange facility...of the energy consumption area because no...Development of in-vessel type control rod......

N. Odano; T. Ishida

2005-12-20T23:59:59.000Z

382

Advanced neutron irradiation system using Texas A&M University Nuclear Science Center Reactor  

E-Print Network [OSTI]

was installed in the irradiation cell of the Texas A&M University Nuclear Science Center Reactor (NSCR). By increasing the thickness of the lead-bismuth alloy, the neutron spectra were shifted into lower energies by the scattering interactions of fast...

Jang, Si Young

2005-11-01T23:59:59.000Z

383

US fast reactor materials and structures program  

SciTech Connect (OSTI)

Materials and structures problems are central to many critical issues concerning the economic competitiveness, reliable performance, and safety of liquid metal fast breeder reactor (LMFBR) power plants. The US Department of Energy has sponsored for many years a national LMFBR materials and structures program. The objectives of the program are (1) to provide the technological basis for assuring that LMFBR components and systems will be free from significant structural failures during their design lifetimes and (2) to develop materials, design methods and criteria, materials property data, and procedures - all aimed at providing for broad flexibility in LMFBR component and system design and operation. Technology areas included in the program are high-temperature structural design; seismic design; mechanical properties design data; fabrication; tribology (friction, wear, and self-welding); coolant technology (sodium and steam/water); advanced structural alloys; and nondestructive testing. It is the purpose of this study to indicate briefly for each of the program's technology areas the objective, the scope, and some significant accomplishments. Future directions for the program are also discussed.

Harms, W.O.; Purdy, C.M.

1984-01-01T23:59:59.000Z

384

WIMSD analysis of the positive coolant void mechanism in the CANDU-3 lattice  

SciTech Connect (OSTI)

The Atomic Energy of Canada Technologies (AECLT) of America is submitting the CANDU 3 reactor system for a Design Certification (CD) with the U.S. NRC. The NRC is presently in the preliminary phase of evaluating this natural uranium fueled, heavy water cooled and moderated reactor system. Brookhaven National Laboratory (BNL) is supplying technical assistance and support, particularly in the analysis of the positive void feedback effect known to be inherent in the CANDU 3 design. The purpose of this paper is to present some results from the WIMSD code that was used to study a representative lattice cell of the CANDU 3 reactor under a voided condition.

Nimnual, S.; Slovik, G.C.

1995-12-31T23:59:59.000Z

385

Large passive pressure tube light water reactor with voided calandria  

SciTech Connect (OSTI)

A reactor concept has been developed that can survive loss-of-coolant accidents (LOCAs) without scram and without replenishing primary coolant inventory while maintaining safe temperature limits on the fuel and pressure tube. The proposed concept is a pressure tube reactor of similar design to Canada deuterium uranium reactors but differing in three key aspects. First, a solid silicon carbide-coated graphite fuel matrix is used in place of fuel pin bundles to enable the dissipation of decay heat from the fuel in the absence of primary coolant. Second, the heavy water coolant in the pressure tubes is replaced by light water, which also serves as the moderator. Finally, the calandria tank, surrounded by a graphite reflector, contains a low-pressure gas instead of heavy water moderator, and this normally voided calandria is connected to a light water heat sink. The cover gas displaces the light water from the calandria during normal operation while during a LOCA or loss of heat sink accident, it allows passive calandria flooding. Calandria flooding also provides redundant and diverse reactor shutdown. The fuel elements can operate under post-critical-heat-flux conditions even at full power without exceeding fuel design limits. The heterogeneous arrangement of the fuel and moderator ensures a negative void coefficient under all circumstances. Although light water is used as both coolant and moderator, the reactor exhibits a high degree of neutron thermalization and a large prompt neutron lifetime, similar to D{sub 2}O-moderated cores. Moreover, the extremely large neutron migration length results in a strongly coupled core with a flat thermal flux profile and inherent stability against xenon spatial oscillations.

Hejzlar, P.; Todreas, N.E.; Driscoll, M.J. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Nuclear Engineering

1996-02-01T23:59:59.000Z

386

RELAP5 Simulation of Thermal-Hydraulic Behavior in a CANDU Reactor - Assessments of RD-14 Experiments  

SciTech Connect (OSTI)

The critical reactor header break and the thermosiphoning experiments in the RD-14 test facility were simulated with the RELAP5/MOD3.1 code. The RELAP5 code has been developed for best-estimate transient simulation of pressurized water reactors and associated systems, but it has not been assessed for a Canada deuterium uranium (CANDU) reactor. Therefore, this study has been initiated with an aim to identify the code applicability in a CANDU reactor by simulating some of the tests performed in the RD-14 facility. The RD-14 test facility at Whiteshell Nuclear Research Establishment is a full-scale pressurized-water loop. The RD-14 is not a scale model of any particular CANDU reactor. Rather, it possesses many geometric features of a CANDU reactor heat transport system and is capable of operating at conditions similar to those expected to occur in a reactor under normal operation and some postulated accident conditions. In this study, two critical reactor header break tests (B8711 and B8713) and three thermosiphoning tests (T8513, T8515, and T8517) were analyzed with the RELAP5 code. The results were compared with experimental data and those of CATHENA performed by Atomic Energy of Canada Ltd. The RELAP5 analyses demonstrate the code's capability to predict reasonably the main phenomena occurring in the transient, in both the qualitative and the quantitative view. However, some discrepancies after the emergency coolant injection for the critical break case and also related to the behaviors of the mass flow rate and the primary pressure for the thermosiphoning case were observed.

Lee, Sukho; Kim, In-Goo [Korea Institute of Nuclear Safety (Korea, Republic of)

2000-04-15T23:59:59.000Z

387

System and method for the analysis of one or more compounds and/or species produced by a solution-based nuclear reactor  

SciTech Connect (OSTI)

The present invention relates generally to both a system and method for determining the composition of an off-gas from a solution nuclear reactor (e.g., an Aqueous Homogeneous Reactor (AHR)) and the composition of the fissioning solution from those measurements. In one embodiment, the present invention utilizes at least one quadrupole mass spectrometer (QMS) in a system and/or method designed to determine at least one or more of: (i) the rate of production of at least one gas and/or gas species from a nuclear reactor; (ii) the effect on pH by one or more nitrogen species; (iii) the rate of production of one or more fission gases; and/or (iv) the effect on pH of at least one gas and/or gas species other than one or more nitrogen species from a nuclear reactor.

Policke, Timothy A; Nygaard, Eric T

2014-05-06T23:59:59.000Z

388

Microsoft Word - EC Sodium coolant removal.doc  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

1 1 SECTION A. Project Title: MFC - EBR-II Sodium Removal/RCRA Closure Activities SECTION B . Project Description The proposed action will remove the sodium from the Experimental Breeder Reactor (EBR)-II piping system and tanks to achieve clean-closure for eventual decommissioning, deactivation and demolition (DD&D). The clean-closure will be completed in compliance with the EBR-II Hazardous Waste Management Act/Resource Conservation and Recovery Act (HWMA/RCRA) Storage and Treatment Permit PER-120, which includes the closure plan. EBR-II is located at the Materials and Fuels Complex at the Idaho National Laboratory. The EBR-II DD&D actions will be addressed under the Comprehensive Environmental Response Compensation, and Liability Act, specifically, the Engineering Evaluation/Cost

389

Nuclear proliferation and civilian nuclear power. Report of the Nonproliferation Alternative Systems Assessment Program. Volume IX. Reactor and fuel cycle description  

SciTech Connect (OSTI)

The Nonproliferation Alterntive Systems Assessment Program (NASAP) has characterized and assessed various reactor/fuel-cycle systems. Volume IX provides, in summary form, the technical descriptions of the reactor/fuel-cycle systems studied. This includes the status of the system technology, as well as a discussion of the safety, environmental, and licensing needs from a technical perspective. This information was then used in developing the research, development, and demonstration (RD and D) program, including its cost and time frame, to advance the existing technology to the level needed for commercial use. Wherever possible, the cost data are given as ranges to reflect the uncertainties in the estimates.

Not Available

1980-06-01T23:59:59.000Z

390

Generation -IV Reactor Concepts  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Generation-IV Reactor Concepts Generation-IV Reactor Concepts Thomas H. Fanning Argonne National Laboratory 9700 South Cass Avenue Argonne, Illinois 60439, USA The Generation-IV International Forum (GIF) is a multi-national research and development (R&D) collaboration. The GIF pursues the development of advanced, next generation reactor technology with goals to improve: a) sustainability (effective fuel utilization and minimization of waste) b) economics (competitiveness with respect to other energy sources) c) safety and reliability (e.g., no need for offsite emergency response), and d) proliferation resistance and physical protection The GIF Technology Roadmap exercise selected six generic systems for further study: the Gas- cooled Fast Reactor (GFR), the Lead-cooled Fast Reactor (LFR), the Molten Salt Reactor (MSR),

391

Conceptual design analysis of an MHD power conversion system for droplet-vapor core reactors. Final report  

SciTech Connect (OSTI)

A nuclear driven magnetohydrodynamic (MHD) generator system is proposed for the space nuclear applications of few hundreds of megawatts. The MHD generator is coupled to a vapor-droplet core reactor that delivers partially ionized fissioning plasma at temperatures in range of 3,000 to 4,000 K. A detailed MHD model is developed to analyze the basic electrodynamics phenomena and to perform the design analysis of the nuclear driven MHD generator. An incompressible quasi one dimensional model is also developed to perform parametric analyses.

Anghaie, S.; Saraph, G.

1995-12-31T23:59:59.000Z

392

The development and operational testing of an experimental reactor for gas-liquid-solid reaction systems at high temperatures and pressures  

E-Print Network [OSTI]

shaft. With the impeller in place and rotating, gas was drawn into the top port and ejected at the impeller mount. The reactor pressure was monitored via the transducer port. The transducer was a Viatran Pressure Transducer, model 103. The liquid...THE DEVELOPMENT AND OPERATIONAL TESTING OF AN EXPERIMENTAL REACTOR FOR GAS-LIQUID-SOLID REACTION SYSTEMS AT HIGH TEMPERATURES AND PRESSURES A Thesis by RICHARD KENNETH HESS Submitted to the Graduate College of Texas A&M University in partial...

Hess, Richard Kenneth

2012-06-07T23:59:59.000Z

393

Thermal analysis and design of a passive reflux condenser for the simplified boiling water reactor  

SciTech Connect (OSTI)

At present, the advanced light water reactors (ALWRS) in the United States are being designed to remove reactor decay heat for a period of 72 h following a postulated loss-of-coolant accident (LOCA). The water in the pools external to the containment is evaporated or boiled off to remove the decay heat. It is presumed that the water in the pools can be replenished within 72 h through operator actions or outside assistance. Some countries in Europe require that the plant be designed to remove the reactor decay heat for a much longer duration than 72 h without external assistance. This paper presents an analysis and design of a passive heat exchanger called a reflux condenser (RC), which was considered for an ALWR-the 600-MW(electric) simplified boiling water reactor. The RC is required to condense the steam formed when the water in the pool in which the passive containment cooling system (PCCS) is immersed boils following a LOCA. The RCs are nuclear non-safety related. This paper presents steady-state performance of an RC at various outdoor air dry-bulb temperatures under still air conditions.

Bijlani, C.; Patti, F. (Burns Roe Inc., Oradell, NJ (United States)); Prasad, V. (SUNY, Stony Brook, NY (United States))

1993-01-01T23:59:59.000Z

394

An experimental test plan for the characterization of molten salt thermochemical properties in heat transport systems  

SciTech Connect (OSTI)

Molten salts are considered within the Very High Temperature Reactor program as heat transfer media because of their intrinsically favorable thermo-physical properties at temperatures starting from 300 C and extending up to 1200 C. In this context two main applications of molten salt are considered, both involving fluoride-based materials: as primary coolants for a heterogeneous fuel reactor core and as secondary heat transport medium to a helium power cycle for electricity generation or other processing plants, such as hydrogen production. The reference design concept here considered is the Advanced High Temperature Reactor (AHTR), which is a large passively safe reactor that uses solid graphite-matrix coated-particle fuel (similar to that used in gas-cooled reactors) and a molten salt primary and secondary coolant with peak temperatures between 700 and 1000 C, depending upon the application. However, the considerations included in this report apply to any high temperature system employing fluoride salts as heat transfer fluid, including intermediate heat exchangers for gas-cooled reactor concepts and homogenous molten salt concepts, and extending also to fast reactors, accelerator-driven systems and fusion energy systems. The purpose of this report is to identify the technical issues related to the thermo-physical and thermo-chemical properties of the molten salts that would require experimental characterization in order to proceed with a credible design of heat transfer systems and their subsequent safety evaluation and licensing. In particular, the report outlines an experimental R&D test plan that would have to be incorporated as part of the design and operation of an engineering scaled facility aimed at validating molten salt heat transfer components, such as Intermediate Heat Exchangers. This report builds on a previous review of thermo-physical properties and thermo-chemical characteristics of candidate molten salt coolants that was generated as part of the same project [1]. However, this work focuses on two materials: the LiF-BeF2 eutectic (67 and 33 mol%, respectively, also known as flibe) as primary coolant and the LiF-NaF-KF eutectic (46.5, 11.5, and 52 mol%, respectively, also known as flinak) as secondary heat transport fluid. At first common issues are identified, involving the preparation and purification of the materials as well as the development of suitable diagnostics. Than issues specific to each material and its application are considered, with focus on the compatibility with structural materials and the extension of the existing properties database.

Pattrick Calderoni

2010-09-01T23:59:59.000Z

395

CANDU reactors, their regulation in Canada, and the identification of relevant NRC safety issues  

SciTech Connect (OSTI)

Atomic Energy of Canada, Limited (AECL) and its subsidiary in the US, are considering submitting the CANDU 3 design for standard design certification under 10 CFR Part 52. CANDU reactors are pressurized heavy water power reactors. They have some substantially different safety responses and safety systems than the LWRs that the commercial power reactor licensing regulations of the US Nuclear Regulatory Commission (NRC) have been developed to deal with. In this report, the authors discuss the basic design characteristics of CANDU reactors, specifically of the CANDU 3 where possible, and some safety-related consequences of these characteristics. The authors also discuss the Canadian regulatory provisions, and the CANDU safety systems that have evolved to satisfy the Canadian regulatory requirements as of December 1992. Finally, the authors identify NRC regulations, mainly in 10 CFR Parts 50 and 100, with issues for CANDU 3 reactor designs. In all, eleven such regulatory issues are identified. They are: (1) the ATWS rule ({section}50.62); (2) station blackout ({section}50.63); (3) conformance with Standard Review Plan (SRP); (4) appropriateness of the source term ({section}50.34(f) and {section}100.11); (5) applicability of reactor coolant pressure boundary (RCPB) requirements ({section}50.55a, etc); (6) ECCS acceptance criteria ({section}50.46)(b); (7) combustible gas control ({section}50.44, etc); (8) power coefficient of reactivity (GDC 11); (9) seismic design (Part 100); (10) environmental impacts of the fuel cycle ({section}51.51); and (11) (standards {section}50.55a).

Charak, I.; Kier, P.H. [Argonne National Lab., IL (United States)

1995-04-01T23:59:59.000Z

396

Proposed and existing passive and inherent safety-related structures, systems, and components (building blocks) for advanced light-water reactors  

SciTech Connect (OSTI)

A nuclear power plant is composed of many structures, systems, and components (SSCs). Examples include emergency core cooling systems, feedwater systems, and electrical systems. The design of a reactor consists of combining various SSCs (building blocks) into an integrated plant design. A new reactor design is the result of combining old SSCs in new ways or use of new SSCs. This report identifies, describes, and characterizes SSCs with passive and inherent features that can be used to assure safety in light-water reactors. Existing, proposed, and speculative technologies are described. The following approaches were used to identify the technologies: world technical literature searches, world patent searches, and discussions with universities, national laboratories and industrial vendors. 214 refs., 105 figs., 26 tabs.

Forsberg, C.W.; Moses, D.L.; Lewis, E.B.; Gibson, R.; Pearson, R.; Reich, W.J.; Murphy, G.A.; Staunton, R.H.; Kohn, W.E.

1989-10-01T23:59:59.000Z

397

The TMI defueling project fuel debris removal system  

SciTech Connect (OSTI)

The Three Mile Island (TMI) unit 2 pressurized water reactor loss-of-coolant accident on March 28, 1979, presented the nuclear community with many challenging remediation problems. A plethora of techniques, systems, and tools have been employed for the recovery and packaging of the postaccident configuration of the reactor core. Of particular difficulty was the removal of the fuel debris located beneath the lower core support structure. Fuel debris located beneath the lower core support structure was the result of rapid cooling of the previously molten UO{sub 2} and ZrO{sub 2}, causing formation of a ceramic like rubble. Approximately 19,100 kg of this rubble settled beneath the lower core support structure and onto the lower head of the reactor containment vessel. The development and implementation of a debris collection system based on the air lift principle proved to be an effective method for gathering the fuel debris from beneath the lower core support structure.

Burge, B. (EG and G Idaho, Inc., Idaho Falls (United States))

1992-01-01T23:59:59.000Z

398

System transient response to loss of off-site power  

SciTech Connect (OSTI)

A simultaneous trip of the reactor, main circulation pumps, secondary coolant pumps, and pressurizer pump due to loss of off-site power at the High Flux Isotope Reactor (HFIR) located at the Oak Ridge National Laboratory (ORNL) has been analyzed to estimate available safety margin. A computer model based on the Modular Modeling System code has been used to calculate the transient response of the system. The reactor depressurizes from 482.7 psia down to about 23 psia in about 50 seconds and remains stable thereafter. Available safety margin has been estimated in terms of the incipient boiling heat flux ratio. It is a conservative estimate due to assumed less than available primary and secondary flows and higher than normal depressurization rate. The ratio indicates no incipient boiling conditions at the hot spot. No potential damage to the fuel is likely to occur during this transient. 2 refs., 6 figs.

Sozer, A.

1990-01-01T23:59:59.000Z

399

CFD analysis of bubble hydrodynamics in a fuel reactor for a hydrogen-fueled chemical looping combustion system  

Science Journals Connector (OSTI)

Abstract This study investigates the temporal development of bubble hydrodynamics in the fuel reactor of a hydrogen-fueled chemical looping combustion (CLC) system by using a computational model. The model also investigates the molar fraction of products in gas and solid phases. The study assists in developing a better understanding of the CLC process, which has many advantages such as being a potentially promising candidate for an efficient carbon dioxide capture technology. The study employs the kinetic theory of granular flow. The reactive fluid dynamic system of the fuel reactor is customized by incorporating the kinetics of an oxygen carrier reduction into a commercial computational fluid dynamics (CFD) code. An Eulerian multiphase treatment is used to describe the continuum two-fluid model for both gas and solid phases. CaSO4 and H2 are used as an oxygen carrier and a fuel, respectively. The computational results are validated with the experimental and numerical results available in the open literature. The CFD simulations are found to capture the features of the bubble formation, rise and burst in unsteady and quasi-steady states very well. The results show a significant increase in the conversion rate with higher dense bed height, lower bed width, higher free board height and smaller oxygen carrier particles which upsurge an overall performance of the CLC plant.

Atal Bihari Harichandan; Tariq Shamim

2014-01-01T23:59:59.000Z

400

Design and analysis of megawatt-class heat-pipe reactor concepts  

SciTech Connect (OSTI)

There is growing interest in finding an alternative to diesel-powered systems at locations removed from a reliable electrical grid. One promising option is a 1- to 10-MW mobile reactor system, that could provide robust, self-contained, and long-term ({>=} 5 years) power in any environment. The reactor and required infrastructure could be transported to any location within one or a few standard transport containers. Heat pipe reactors, using alkali metal heat pipes, are perfectly suited for mobile applications because their nature is inherently simpler, smaller, and more reliable than 'traditional' reactors that rely on pumped coolant through the core. This paper examines a heat pipe reactor that is fabricated and shipped as six identical core segments. Each core segment includes a heat-pipe-to-gas heat exchanger that is coupled to the condenser end of the heat pipes. The reference power conversion system is a CO{sub 2}-Brayton system. The segments by themselves are deeply subcritical during transport, and they would be locked into an operating configuration (with control inserted) at the final destination. Two design options are considered: a near-term option and an advanced option. The near-term option is a 5-MWt concept that uses uranium-dioxide fuel, a stainless-steel structure, and potassium as the heat-pipe working fluid. The advanced option is a 15-MWt concept that uses uranium-nitride fuel, a molybdenum/TZM structure, and sodium as the heat-pipe working fluid. The materials used in the advanced option allow for higher temperatures and power densities, and enhanced power throughput in the heat pipes. Higher powers can be obtained from both concepts by increasing the core size and the number of heat pipes. (authors)

Poston, D.; Kapernick, R. [Los Alamos National Laboratory, MS C921, Los Alamos, NM 87545 (United States)

2012-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Results of tritium experiments on ceramic electrolysis cells and palladium diffusers for application to fusion reactor fuel cleanup systems  

SciTech Connect (OSTI)

Tritium tests at the Tritium Systems Test Assembly have demonstrated that ceramic electrolysis cells and palladium alloy diffuser developed in Japan are possible components for a fusion reactor fuel cleanup system. Both components have been successfully operated with tritium for over a year. A failure of the first electrolysis cell was most likely the result of an over voltage on the ceramic. A simple circuit was developed to eliminate this mode of failure. The palladium diffusers tubes exhibited some degradation of mechanical properties as a result of the build up of helium from the tritium decay, after 450 days of operation with tritium, however the effects were not significant enough to affect the performance. New models of the diffuser and electrolysis cell, providing higher flow rates and more tritium compatible designs are currently being tested with tritium. 8 refs., 5 figs.

Carlson, R.V.; Binning, K.E.; Konishi, S.; Yoshida, H.; Naruse, Y.

1987-01-01T23:59:59.000Z

402

Experimental and Thermalhydraulic Code Assessment of the Transient Behavior of the Passive Condenser System in an Advanced Boiling Water Reactor  

SciTech Connect (OSTI)

The main goal of the project was to study analytically and experimentally the condensation heat transfer for the passive condenser system such as GE Economic Simplified Boiling Water Reactor (ESBWR). The effect of noncondensable gas in condenser tube and the reduction of secondary pool water level to the condensation heat transfer coefficient was the main focus in this research. The objectives of this research were to : 1) obtain experimental data on the local and tube averaged condensation heat transfer rates for the PCCS with non-condensable and with change in the secondary pool water, 2) assess the RELAP5 and TRACE computer code against the experimental data, and 3) develop mathematical model and ehat transfer correlation for the condensation phenomena for system code application. The project involves experimentation, theoretical model development and verification, and thermal- hydraulic codes assessment.

S.T. Revankar; W. Zhou; Gavin Henderson

2008-07-08T23:59:59.000Z

403

TOKOPS: Tokamak Reactor Operations Study: The influence of reactor operations on the design and performance of tokamaks with solid-breeder blankets: Final report  

SciTech Connect (OSTI)

Reactor system operation and procedures have a profound impact on the conception and design of power plants. These issues are studied here using a model tokamak system employing a solid-breeder blanket. The model blanket is one which has evolved from the STARFIRE and BCSS studies. The reactor parameters are similar to those characterizing near-term fusion engineering reactors such as INTOR or NET (Next European Tokamak). Plasma startup, burn analysis, and methods for operation at various levels of output power are studied. A critical, and complicating, element is found to be the self-consistent electromagnetic response of the system, including the presence of the blanket and the resulting forces and loadings. Fractional power operation, and the strategy for burn control, is found to vary depending on the scaling law for energy confinement, and an extensive study is reported. Full-power reactor operation is at a neutron wall loading pf 5 MW/m/sup 2/ and a surface heat flux of 1 MW/m/sup 2/. The blanket is a pressurized steel module with bare beryllium rods and low-activation HT-9-(9-C-) clad LiAlO/sub 2/ rods. The helium coolant pressure is 5 MPa, entering the module at 297/sup 0/C and exiting at 550/sup 0/C. The system power output is rated at 1000 MW(e). In this report, we present our findings on various operational scenarios and their impact on system design. We first start with the salient aspects of operational physics. Time-dependent analyses of the blanket and balance of plant are then presented. Separate abstracts are included for each chapter.

Conn, R.W.; Ghoniem, N.M.; Firestone, M.A. (eds.)

1986-09-01T23:59:59.000Z

404

Reactor Safety Research Programs  

SciTech Connect (OSTI)

This document summarizes the work performed by Pacific Northwest Laboratory (PNL) from January 1 through March 31, 1981, for the Division of Reactor Safety Research within the U.S. Nuclear Regulatory Commission (NRC). Evaluations of nondestructive examination (NDE) techniques and instrumentation are reported; areas of investigation include demonstrating the feasibility of determining the strength of structural graphite, evaluating the feasibility of detecting and analyzing flaw growth in reactor pressure boundary systems, examining NDE reliability and probabilistic fracture mechanics, and assessing the integrity of pressurized water reactor (PWR) steam generator tubes where service-induced degradation has been indicated. Experimental data and analytical models are being provided to aid in decision-making regarding pipeto- pipe impacts following postulated breaks in high-energy fluid system piping. Core thermal models are being developed to provide better digital codes to compute the behavior of full-scale reactor systems under postulated accident conditions. Fuel assemblies and analytical support are being provided for experimental programs at other facilities. These programs include loss-ofcoolant accident (LOCA) simulation tests at the NRU reactor, Chalk River, Canada; fuel rod deformation, severe fuel damage, and postaccident coolability tests for the ESSOR reactor Super Sara Test Program, Ispra, Italy; the instrumented fuel assembly irradiation program at Halden, Norway; and experimental programs at the Power Burst Facility, Idaho National Engineering Laboratory (INEL). These programs will provide data for computer modeling of reactor system and fuel performance during various abnormal operating conditions.

Edler, S. K.

1981-07-01T23:59:59.000Z

405

Numerical analysis of turbulent heat transfer in a nuclear reactor coolant channel  

E-Print Network [OSTI]

(I) = 5 ' 5 + 2 ' 5 tt ALOG&YP(I)) VEL&I ~ JX) = UP(I) tt (TAU X VDENS(KPI&)t&t&0 ' 5 tt 3600 ' 0 CONTINUE VEL&KP1 ~ JX) = 0 ~ 0 UP(KPI) = 0 ~ 0 YP&KPI& = 0 ' 0 DO 70 I = It KP1 EPS&I ~ JX) = (VMU(I ) 1 VDENS( I & ) tt ((R(I ) tt&YP(I+I ) ? YP( I...(KP1 ) C &KPI ) = R (KPI )?? VEL (KPI ~ JX1 )?? VDENS (KP1 ) D&KPI) = R&KPI) ?? VDENS&KP1) DO 10 I = 2?20 ' 2 8(I& ~ 4 ' 0 ?? R(I& ?? VEL&I?JXI) ?? T&I?JXI) ?? VDENS&I) C(I) = 4 ' 0 ?? R(I) ?? VEL(I?JXI) ?? VDENS(I) D&I) = 4 ' 0 ?? R&I) ?? VDENS...

Garrard, Clarence William

1965-01-01T23:59:59.000Z

406

Dynamic reliability and risk assessment of the accident localization system of the Ignalina NPP RBMK-1500 reactor  

Science Journals Connector (OSTI)

The paper presents reliability and risk analysis of the RBMK-1500 reactor accident localization system (ALS) (confinement), which prevents radioactive releases to the environment. Reliability of the system was estimated and compared by two methods: the conventional fault tree method and an innovative dynamic reliability model, based on stochastic differential equations. Frequency of radioactive release through ALS was also estimated. The results of the study indicate that conventional fault tree modeling techniques in this case apply high degree of conservatism in the system reliability estimates. One of the purposes of the ALS reliability study was to demonstrate advantages of the dynamic reliability analysis against the conventional fault/event tree methods. The Markovian framework to deal with dynamic aspects of system behavior is presented. Although not analyzed in detail, the framework is also capable of accounting for non-constant component failure rates. Computational methods are proposed to solve stochastic differential equations, including analytical solution, which is possible only for relatively small and simple systems. Other numerical methods, like Monte Carlo and numerical schemes of differential equations are analyzed and compared. The study is finalized with concluding remarks regarding both the studied system reliability and computational methods used.

V. Kopustinskas; J. Augutis; S. Rimkevi?ius

2005-01-01T23:59:59.000Z

407

Fuel Cycle System Analysis Implications of Sodium-Cooled Metal-Fueled Fast Reactor Transuranic Conversion Ratio  

SciTech Connect (OSTI)

If advanced fuel cycles are to include a large number of fast reactors (FRs), what should be the transuranic (TRU) conversion ratio (CR)? The nuclear energy era started with the assumption that they should be breeder reactors (CR > 1), but the full range of possible CRs eventually received attention. For example, during the recent U.S. Global Nuclear Energy Partnership program, the proposal was burner reactors (CR < 1). Yet, more recently, Massachusetts Institute of Technology's "Future of the Nuclear Fuel Cycle" proposed CR [approximately] 1. Meanwhile, the French company EDF remains focused on breeders. At least one of the reasons for the differences of approach is different fuel cycle objectives. To clarify matters, this paper analyzes the impact of TRU CR on many parameters relevant to fuel cycle systems and therefore spans a broad range of topic areas. The analyses are based on a FR physics parameter scan of TRU CR from 0 to [approximately]1.8 in a sodium-cooled metal-fueled FR (SMFR), in which the fuel from uranium-oxide-fueled light water reactors (LWRs) is recycled directly to FRs and FRs displace LWRs in the fleet. In this instance, the FRs are sodium cooled and metal fueled. Generally, it is assumed that all TRU elements are recycled, which maximizes uranium ore utilization for a given TRU CR and waste radiotoxicity reduction and is consistent with the assumption of used metal fuel separated by electrochemical means. In these analyses, the fuel burnup was constrained by imposing a neutron fluence limit to fuel cladding to the same constant value. This paper first presents static, time-independent measures of performance for the LWR [right arrow] FR fuel cycle, including mass, heat, gamma emission, radiotoxicity, and the two figures of merit for materials for weapon attractiveness developed by C. Bathke et al. No new fuel cycle will achieve a static equilibrium in the foreseeable future. Therefore, additional analyses are shown with dynamic, time-dependent measures of performance including uranium usage, TRU inventory, and radiotoxicity to evaluate the complex impacts of transition from the current uranium-fueled LWR system, and other more realistic impacts that may not be intuited from the time-independent steady-state conditions of the end-state fuel cycle. These analyses were performed using the Verifiable Fuel Cycle Simulation Model VISION. Compared with static calculations, dynamic results paint a different picture of option space and the urgency of starting a FR fleet. For example, in a static analysis, there is a sharp increase in uranium utilization as CR exceeds 1.0 (burner versus breeder). However, in dynamic analyses that examine uranium use over the next 1 to 2 centuries, behavior as CR crosses the 1.0 threshold is smooth, and other parameters such as the time required outside of reactors to recycle fuel become important. Overall, we find that there is no unambiguously superior value of TRU CR; preferences depend on the relative importance of different fuel cycle system objectives.

Steven J. Piet; Edward A. Hoffman; Samuel E. Bays; Gretchen E. Matthern; Jacob J. Jacobson; Ryan Clement; David W. Gerts

2013-03-01T23:59:59.000Z

408

Experimental Study of the Effect of Graphite Dispersion on the Heat Transfer Phenomena in a Reactor Cavity Cooling System  

SciTech Connect (OSTI)

An experimental activity was performed to observe and study the effects of graphite dispersion and deposition on thermal-hydraulic phenomena in a reactor cavity cooling system (RCCS). The small-scale RCCS experimental facility (16.5 x 16.5 x 30.4 cm) used for this activity represents half of the reactor cavity with an electrically heated vessel. Water flowing through five vertical pipes removes the heat produced in the vessel and releases it into the environment by mixing with cold water in a large tank. The particle image velocimetry technique was used to study the velocity field of the air inside the cavity. A set of 52 thermocouples was installed in the facility to monitor the temperature profiles of the vessel, pipe walls, and air. Ten grams of a fine graphite powder (average particle size 2 m) was injected into the cavity through a spraying nozzle placed at the bottom of the vessel. The temperatures and air velocity field were recorded and compared with the measurements obtained before the graphite dispersion, showing a decrease of the temperature surfaces that was related to an increase in their emissivity. The results contribute to the understanding of RCCS capability in an accident scenario.

Rodolfo Vaghetto; Luigi Capone; Yassin A. Hassan

2011-05-31T23:59:59.000Z

409

ACHIEVING THE REQUIRED COOLANT FLOW DISTRIBUTION FOR THE ACCELERATOR PRODUCTION OF TRITIUM (APT) TUNGSTEN NEUTRON SOURCE  

SciTech Connect (OSTI)

The Accelerator Production of Tritium neutron source consists of clad tungsten targets, which are concentric cylinders with a center rod. These targets are arranged in a matrix of tubes, producing a large number of parallel coolant paths. The coolant flow required to meet thermal-hydraulic design criteria varies with location. This paper describes the work performed to ensure an adequate coolant flow for each target for normal operation and residual heat-removal conditions.

D. SIEBE; K. PASAMEHMETOGLU

2000-11-01T23:59:59.000Z

410

The mathematical modelling of biomethane production and the growth of methanogenic bacteria in batch reactor systems fed with organic municipal solid waste  

Science Journals Connector (OSTI)

A mathematical model was developed and validated for an anaerobic digestion system of the Organic Fraction of Municipal Solid Wastes (OFMSWs) by using a laboratory-scale system of two Packed Bed Reactors (PBRs). The equations were obtained by the mass balances of methanogenic bacteria of affluent and effluent lixiviated, as well as the interior in each reactor. The methane rate was obtained by multiplying the methanogenic activity. A differential equation was fitted with experimental results to obtain the parameters that best describe methanogenic behaviour. These kinetic parameters were used with the modified logistic equation with the special case n = 1.

Liliana Alzate-Gaviria; Antonino Perez-Hernandez; Hector M. Poggi-Varaldo; P.J. Sebastian

2009-01-01T23:59:59.000Z

411

Viscosity of alumina nanoparticles dispersed in car engine coolant  

SciTech Connect (OSTI)

The present paper, describes our experimental results on the viscosity of the nanofluid prepared by dispersing alumina nanoparticles (<50 nm) in commercial car coolant. The nanofluid prepared with calculated amount of oleic acid (surfactant) was tested to be stable for more than 80 days. The viscosity of the nanofluids is measured both as a function of alumina volume fraction and temperature between 10 and 50 C. While the pure base fluid display Newtonian behavior over the measured temperature, it transforms to a non-Newtonian fluid with addition of a small amount of alumina nanoparticles. Our results show that viscosity of the nanofluid increases with increasing nanoparticle concentration and decreases with increase in temperature. Most of the frequently used classical models severely under predict the measured viscosity. Volume fraction dependence of the nanofluid viscosity, however, is predicted fairly well on the basis of a recently reported theoretical model for nanofluids that takes into account the effect of Brownian motion of nanoparticles in the nanofluid. The temperature dependence of the viscosity of engine coolant based alumina nanofluids obeys the empirical correlation of the type: log ({mu}{sub nf}) = A exp(BT), proposed earlier by Namburu et al. (author)

Kole, Madhusree; Dey, T.K. [Thermophysical Measurements Laboratory, Cryogenic Engineering Centre, Indian Institute of Technology, Kharagpur 721 302 (India)

2010-09-15T23:59:59.000Z

412

A Combined Neutronic-Thermal Hydraulic Model of CERMET NTR Reactor  

SciTech Connect (OSTI)

Abstract. Two different CERMET fueled Nuclear Thermal Propulsion reactors were modeled to determine the optimum coolant channel surface area to volume ratio required to cool a 25,000 lbf rocket engine operating at a specific impulse of 940 seconds. Both reactor concepts were computationally fueled with hexagonal cross section fuel elements having a flat-to-flat distance of 3.51 cm and containing 60 vol.% UO2 enriched to 93wt.%U235 and 40 vol.% tungsten. Coolant channel configuration consisted of a 37 coolant channel fuel element and a 61 coolant channel model representing 0.3 and 0.6 surface area to volume ratios respectively. The energy deposition from decelerating fission products and scattered neutrons and photons was determined using the MCNP monte carlo code and then imported into the STAR-CCM+ computational fluid dynamics code. The 37 coolant channel case was shown to be insufficient in cooling the core to a peak temperature of 3000 K; however, the 61 coolant channel model shows promise for maintaining a peak core temperature of 3000 K, with no more refinements to the surface area to volume ratio. The core was modeled to have a power density of 9.34 GW/m3 with a thrust to weight ratio of 5.7.

Jonathan A. Webb; Brian Gross; William T. Taitano

2011-02-01T23:59:59.000Z

413

A probabilistic safety analysis of incidents in nuclear research reactors  

Science Journals Connector (OSTI)

......System for Research Reactor (IRSRR). Available...System for Research Reactor (IRSRR). Available...76. 7 Manual on reliability data collection for research reactor PSAs. (1992) IAEA...probabilistic safety analysis of incidents in nuclear......

Valdir Maciel Lopes; Gian Maria Agostinho Angelo Sordi; Mauricio Moralles; Tufic Madi Filho

2012-06-01T23:59:59.000Z

414

Design of an Actinide-Burning, Lead or Lead-Bismuth Cooled Reactor that Produces Low-Cost Electricity  

SciTech Connect (OSTI)

The purpose of this Idaho National Engineering and Environmental Laboratory (INEEL) and Massachusetts Institute of Technology (MIT) University Research Consortium (URC) project is to investigate the suitability of lead or lead-bismuth cooled fast reactors for producing low-cost electricity as well as for actinide burning. The goal is to identify and analyze the key technical issues in core neutronics, materials, thermal-hydraulics, fuels, and economics associated with the development of this reactor concept. Work has been accomplished in four major areas of research: core neutronic design, material compatibility, plant engineering, and coolant activation. In the area of core neutronic design, the reactivity vs. burnup and discharge isotopics of both non-fertile and fertile fuels were evaluated. An innovative core for pure actinide burning that uses streaming, fertile-free fuel assemblies was studied in depth. This particular core exhibits excellent reactivity performance upon coolant voiding, even for voids that occur in the core center, and has a transuranic (TRU) destruction rate that is comparable to the proposed accelerator transmutation of waste (ATW) facility. These studies suggest that a core can be designed to achieve a long life while maintaining safety and minimizing waste. In the area of material compatibility studies, an experimental apparatus for the investigation of the flow-assisted dissolution and precipitation (corrosion) of potential fuel cladding and structural materials has been designed and built at the INEEL. The INEEL forced-convection corrosion cell consists of a small heated vessel with a shroud and gas flow system. The corrosion cell is being used to test steel that is commercially available in the United States to temperatures above 650°C. Progress in plant engineering was made for two reactor concepts, one utilizing an indirect cycle with heat exchangers and the other utilizing a direct-contact steam cycle. The evaluation of the indirect cycle designs has investigated the effects of various parameters to increase electric production at full power. For the direct-contact reactor, major issues related to the direct-contact heat transfer rate and entrainment and carryover of liquid lead-bismuth to the turbine have been identified and analyzed. An economic analysis approach was also developed to determine the cost of electricity production in the lead-bismuth reactor. The approach will be formulated into a model and applied to develop scientific cost estimates for the different reactor designs and thus aid in the selection of the most economic option. In the area of lead-bismuth coolant activation, the radiological hazard was evaluated with particular emphasis on the direct-contact reactor. In this system, the lack of a physical barrier between the primary and secondary coolant favors the release of the alpha-emitter Po?210 and its transport throughout the plant. Modeling undertaken on the basis of the scarce information available in the literature confirmed the importance of this issue, as well as the need for experimental work to reduce the uncertainties on the basic characteristics of volatile polonium chemical forms.

Mac Donald, Philip Elsworth; Weaver, Kevan Dean; Davis, Cliff Bybee; MIT folks

2000-07-01T23:59:59.000Z

415

Reliability study of a special decay heat removal system of a gas-cooled fast reactor demonstrator  

Science Journals Connector (OSTI)

Abstract The European roadmap toward the development of generation IV concepts addresses the safety and reliability assessment of the special system designed for decay heat removal of a gas-cooled fast reactor demonstrator (GFRD). The envisaged system includes the combination of both active and passive means to accomplish the fundamental safety function. Failure probabilities are calculated on various system configurations, according to either pressurized or depressurized accident events under investigation, and integrated with probabilities of occurrence of corresponding hardware components and natural circulation performance assessment. The analysis suggests the improvement of measures against common cause failures (CCF), in terms of an appropriate diversification among the redundant systems, to reduce the system failure risk. Particular emphasis is placed upon passive system reliability assessment, being recognized to be still an open issue, and the approach based on the functional reliability is adopted to address the point. Results highlight natural circulation as a challenging factor for the decay heat removal safety function accomplishment by means of passive devices. With the models presented here, the simplifying assumptions and the limited scenarios considered according to the level of definition of the design, where many systems are not yet established, one can conclude that attention has to be paid to the functional aspects of the passive system, i.e. the ones not pertaining to the “hardware” of the system. In this article the results of the analysis are discussed, where the effects of the analytical assumptions, design options, accident managements on the reliability are examined. The design diversity of the components undergoing \\{CCFs\\} can be effective for the improvement and some accident management measures are also possible by making use of the long grace period in GFRD.

Luciano Burgazzi

2014-01-01T23:59:59.000Z

416

Incorporating reliability analysis into the design of passive cooling systems with an application to a gas-cooled reactor  

Science Journals Connector (OSTI)

A time-dependent reliability evaluation of a two-loop passive decay heat removal (DHR) system was performed as part of the iterative design process for a helium-cooled fast reactor. The system was modeled using RELAP5-3D. The uncertainties in input parameters were assessed and were propagated through the model using Latin hypercube sampling. An important finding was the discovery that the smaller pressure loss through the DHR heat exchanger than through the core would make the flow to bypass the core through one DHR loop, if two loops operated in parallel. This finding is a warning against modeling only one lumped DHR loop and assuming that n of them will remove n times the decay power. Sensitivity analyses revealed that there are values of some input parameters for which failures are very unlikely. The calculated conditional (i.e., given the LOCA) failure probability was deemed to be too high leading to the identification of several design changes to improve system reliability. This study is an example of the kinds of insights that can be obtained by including a reliability assessment in the design process. It is different from the usual use of PSA in design, which compares different system configurations, because it focuses on the thermal–hydraulic performance of a safety function.

Francisco J. Mackay; George E. Apostolakis; Pavel Hejzlar

2008-01-01T23:59:59.000Z

417

Application of LBB to high energy pipings of a pressurized water reactor in Korea  

Science Journals Connector (OSTI)

The application of the leak before break (LBB) technology to the newly constructed pressurized water reactors (PWRs) has been approved in Korea for several high energy systems that can meet rigorous acceptance criteria. The LBB application in Korea is based on the US Nuclear Regulatory Commision (USNRC) requirements. The purpose of the LBB evaluation is to eliminate the dynamic effects associated with the postulated double-ended guillotine break (DEGB) from design basis loads, as well as to eliminate pipe whip restraints and jet impingement barriers. There were several issues on the application of LBB to the primary coolant loop and the pressurizer surge line. Of concern were the material properties for the carbon steel for the primary coolant loop, estimation of the crack opening area at the pipe-to-nozzle interface considering the asymmetry, and the leakage crack size which barely meets the required margin of 2 for the surge line, etc. Some additional work was required by the safety authority to maintain the global safety of the plant at a sufficient level. This paper describes the regulatory application of LBB in Korea, and the issues encountered during the regulatory review.

Jeong-Bae Lee; Young Hwan Choi

1999-01-01T23:59:59.000Z

418

Technical Information on the Carbonation of the EBR-II Reactor, Summary Report Part 2: Application to EBR-II Primary Sodium System and Related Systems  

SciTech Connect (OSTI)

Residual sodium is defined as sodium metal that remains behind in pipes, vessels, and tanks after the bulk sodium metal has been melted and drained from such components. The residual sodium has the same chemical properties as bulk sodium, and differs from bulk sodium only in the thickness of the sodium deposit. Typically, sodium is considered residual when the thickness of the deposit is less than 5-6 cm. This residual sodium must be removed or deactivated when a pipe, vessel, system, or entire reactor is permanently taken out of service, in order to make the component or system safer and/or to comply with decontamination and decomissioning regulations. As an alternative to the established residual sodium deactivation techniques (steam-and-nitrogen, wet vapor nitrogen, etc.), a technique involving the use of moisture and carbon dioxide has been developed. With this technique, sodium metal is converted into sodium bicarbonate by reacting it with humid carbon dioxide. Hydrogen is emitted as a by-product. This technique was first developed in the laboratory by exposing sodium samples to humidifed carbon dioxide under controlled conditions, and then demonstrated on a larger scale by treating residual sodium within the Experimental Breeder Reactor II (EBR-II) secondary cooling system, followed by the primary cooling system, respectively. The EBR-II facility is located at the Idaho National Laboratory (INL) in southeastern Idaho, USA. This report is Part 2 of a two-part report. This second report provides a supplement to the first report and describes the application of the humdidified carbon dioxide technique ("carbonation") to the EBR-II primary tank, primary cover gas systems, and the intermediate heat exchanger. Future treatment plans are also provided.

Steven R. Sherman; Collin J. Knight

2006-03-01T23:59:59.000Z

419

Experimental Study of the Thermal-Hydraulic Phenomena in the Reactor Cavity Cooling System and Analysis of the Effects of Graphite Dispersion  

E-Print Network [OSTI]

An experimental activity was performed to observe and study the effects of graphite dispersion and deposition on thermal hydraulic phenomena in a Reactor Cavity Cooling System (RCCS). The small scale RCCS experimental facility (16.5cm x 16.5cm x 30...

Vaghetto, Rodolfo

2012-07-16T23:59:59.000Z

420

Design of Complex Systems to Achieve Passive Safety: Natural Circulation Cooling of Liquid Salt Pebble Bed Reactors  

E-Print Network [OSTI]

Safety. The Accident at TEPCO’s Fukushima Nuclear Power2: Accident and Thermal Fluids Analysis PIRTs. (Nuclearmolten nuclear reactor core debris following accidents such

Scarlat, Raluca Olga

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "reactor coolant system" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

E-Print Network 3.0 - anaerobic reactor systems Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Sources of organic matter... -processing wastes, and industrial wastes. A typical biogas system consists of manure collection, anaerobic digestion... and carbon credits. The...

422

GT-MHR power conversion system: Design status and technical issues  

SciTech Connect (OSTI)

The Modular Helium Reactor (MHR) builds on 30 years of international gas-cooled reactor experience utilizing the unique properties of helium gas coolant, graphite moderator and coated particle fuel. To efficiently utilize the high temperature potential of the MHR, an innovative power conversion system has been developed featuring an intercooled and recuperated gas turbine. The gas turbine replaces a conventional steam turbine and its many auxiliary components. The Power Conversion System converts the thermal energy of the helium directly into electrical energy utilizing a closed Brayton cycle. The Power Conversion System draws on even more years of experience than the MHR: the world`s first closed-cycle plant, fossil fired and utilizing air as working fluid, started operation in Switzerland in 1939. Shortly thereafter, in 1945, the coupling of a closed-cycle plant to a nuclear heat generation system was conceived. Directly coupling the closed-cycle gas turbine concept to a modern, passively safe nuclear reactor opens a new chapter in power generation technology and brings with it various design challenges. Some of these challenges are associated with the direct coupling of the Power Conversion System to a nuclear reactor. Since the primary coolant is also the working fluid, the Power Conversion System has to be designed for reactor radionuclide plateout. As a result, issues like component maintainability and replaceability, and fission product effects on materials must be addressed. Other issues concern the integration of the Power Conversion System components into a single vessel. These issues include the selection of key technologies for the power conversion components such as submerged generator, magnetic bearings, seals, compact heat exchangers, and the overall system layout.

Etzel, K.; Baccaglini, G.; Schwartz, A. [General Atomics, San Diego, CA (United States); Hillman, S.; Mathis, D. [AlliedSignal Aerospace, Tempe, AZ (United States)

1994-12-01T23:59:59.000Z