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Note: This page contains sample records for the topic "approximate boiling range" 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.


1

Film boiling of saturated liquid flowing upward through a heated tube : high vapor quality range  

E-Print Network [OSTI]

Film boiling of saturated liquid flowing upward through a uniformly heated tube has been studied for the case in which pure saturated liquid enters the tube and nearly saturated vapor is discharged. Since a previous study ...

Laverty, W. F.

1964-01-01T23:59:59.000Z

2

Range-separated density-functional theory with random phase approximation: Detailed formalism and illustrative applications  

E-Print Network [OSTI]

Range-separated density-functional theory with random phase approximation: Detailed formalism-body theory, we present the details of a formally exact adiabatic-connection fluctuation-dissipation density-functional´an, Phys. Rev. Lett. 102, 096404 (2009). Range-separated density-functional theory approaches combining

Boyer, Edmond

3

Analytical Energy Gradients in Range-Separated Hybrid Density Functional Theory with Random Phase Approximation  

E-Print Network [OSTI]

Analytical forces have been derived in the Lagrangian framework for several random phase approximation (RPA) correlated total energy methods based on the range separated hybrid (RSH) approach, which combines a short-range density functional approximation for the short-range exchange-correlation energy with a Hartree-Fock-type long-range exchange and RPA long-range correlation. The RPA correlation energy has been expressed as a ring coupled cluster doubles (rCCD) theory. The resulting analytical gradients have been implemented and tested for geometry optimization of simple molecules and intermolecular charge transfer complexes, where intermolecular interactions are expected to have a non-negligible effect even on geometrical parameters of the monomers.

Mussard, Bastien; Ángyán, János G

2015-01-01T23:59:59.000Z

4

Low-energy parameters of neutron-neutron interaction in the effective-range approximation  

SciTech Connect (OSTI)

The effect of the mass difference between the charged and neutral pions on the low-energy parameters of nucleon-nucleon interaction in the {sup 1}S{sub 0} state is studied in the effective-range approximation. On the basis of experimental values of the singlet parameters of neutron-proton scattering and the experimental value of the virtual-state energy for the neutron-neutron systemin the {sup 1}S{sub 0} state, the following values were obtained for the neutron-neutron scattering length and effective range: a{sub nn} = -16.59(117) fm and r{sub nn} = 2.83(11) fm. The calculated values agree well with present-day experimental results.

Babenko, V. A.; Petrov, N. M. [National Academy of Sciences of Ukraine, Bogolyubov Institute for Theoretical Physics (Ukraine)

2013-06-15T23:59:59.000Z

5

Enhanced convective and film boiling heat transfer by surface gas injection  

SciTech Connect (OSTI)

Heat transfer measurements were made for stable film boiling of water over a horizontal, flat stainless steel plate from the minimum film boiling point temperature, T{sub SURFACE} {approximately}500K, to T{sub SURFACE} {approximately}950K. The pressure at the plate was approximately 1 atmosphere and the temperature of the water pool was maintained at saturation. The data were compared to the Berenson film-boiling model, which was developed for minimum film-boiling-point conditions. The model accurately represented the data near the minimum film-boiling point and at the highest temperatures measured, as long it was corrected for the heat transferred by radiation. On the average, the experimental data lay within {plus_minus}7% of the model. Measurements of heat transfer were made without film boiling for nitrogen jetting into an overlying pool of water from nine 1-mm- diameter holes, drilled in the heat transfer plate. The heat flux was maintained constant at approximately 26.4 kW/m{sup 2}. For water-pool heights of less than 6cm the heat transfer coefficient deceased linearly with a decrease in heights. Above 6cm the heat transfer coefficient was unaffected. For the entire range of gas velocities measured [0 to 8.5 cm/s], the magnitude of the magnitude of the heat transfer coefficient only changed by approximately 20%. The heat transfer data bound the Konsetov model for turbulent pool heat transfer which was developed for vertical heat transfer surfaces. This agreement suggests that surface orientation may not be important when the gas jets do not locally affect the surface heat transfer. Finally, a database was developed for heat transfer from the plate with both film boiling and gas jetting occurring simultaneously, in a pool of water maintained at its saturation temperature. The effect of passing nitrogen through established film boiling is to increase the heat transfer from that surface. 60 refs.

Duignan, M.R.; Greene, G.A. [Brookhaven National Lab., Upton, NY (United States); Irvine, T.F., Jr. [State Univ. of New York, Stony Brook, NY (United States). Dept. of Mechanical Engineering

1992-04-01T23:59:59.000Z

6

Enhanced convective and film boiling heat transfer by surface gas injection  

SciTech Connect (OSTI)

Heat transfer measurements were made for stable film boiling of water over a horizontal, flat stainless steel plate from the minimum film boiling point temperature, T{sub SURFACE} {approximately}500K, to T{sub SURFACE} {approximately}950K. The pressure at the plate was approximately 1 atmosphere and the temperature of the water pool was maintained at saturation. The data were compared to the Berenson film-boiling model, which was developed for minimum film-boiling-point conditions. The model accurately represented the data near the minimum film-boiling point and at the highest temperatures measured, as long it was corrected for the heat transferred by radiation. On the average, the experimental data lay within {plus minus}7% of the model. Measurements of heat transfer were made without film boiling for nitrogen jetting into an overlying pool of water from nine 1-mm- diameter holes, drilled in the heat transfer plate. The heat flux was maintained constant at approximately 26.4 kW/m{sup 2}. For water-pool heights of less than 6cm the heat transfer coefficient deceased linearly with a decrease in heights. Above 6cm the heat transfer coefficient was unaffected. For the entire range of gas velocities measured (0 to 8.5 cm/s), the magnitude of the magnitude of the heat transfer coefficient only changed by approximately 20%. The heat transfer data bound the Konsetov model for turbulent pool heat transfer which was developed for vertical heat transfer surfaces. This agreement suggests that surface orientation may not be important when the gas jets do not locally affect the surface heat transfer. Finally, a database was developed for heat transfer from the plate with both film boiling and gas jetting occurring simultaneously, in a pool of water maintained at its saturation temperature. The effect of passing nitrogen through established film boiling is to increase the heat transfer from that surface. 60 refs.

Duignan, M.R.; Greene, G.A. (Brookhaven National Lab., Upton, NY (United States)); Irvine, T.F., Jr. (State Univ. of New York, Stony Brook, NY (United States). Dept. of Mechanical Engineering)

1992-04-01T23:59:59.000Z

7

Window-based method for approximating the Hausdorff in three-dimensional range imagery  

DOE Patents [OSTI]

One approach to pattern recognition is to use a template from a database of objects and match it to a probe image containing the unknown. Accordingly, the Hausdorff distance can be used to measure the similarity of two sets of points. In particular, the Hausdorff can measure the goodness of a match in the presence of occlusion, clutter, and noise. However, existing 3D algorithms for calculating the Hausdorff are computationally intensive, making them impractical for pattern recognition that requires scanning of large databases. The present invention is directed to a new method that can efficiently, in time and memory, compute the Hausdorff for 3D range imagery. The method uses a window-based approach.

Koch, Mark W. (Albuquerque, NM)

2009-06-02T23:59:59.000Z

8

A study of electrowetting-assisted boiling  

E-Print Network [OSTI]

The classical theory of boiling heat transfer based on bubble dynamics is explained and includes a full derivation of the Rohsenow boiling correlation. An alternative, more accurate correlation for determining boiling heat ...

Bralower, Harrison L. (Harrison Louis)

2011-01-01T23:59:59.000Z

9

Scalar relativistic computations of nuclear magnetic shielding and g-shifts with the zeroth-order regular approximation and range-separated hybrid density functionals  

SciTech Connect (OSTI)

Density functional theory (DFT) calculations of NMR chemical shifts and molecular g-tensors with Gaussian-type orbitals are implemented via second-order energy derivatives within the scalar relativistic zeroth order regular approximation (ZORA) framework. Nonhybrid functionals, standard (global) hybrids, and range-separated (Coulomb-attenuated, long-range corrected) hybrid functionals are tested. Origin invariance of the results is ensured by use of gauge-including atomic orbital (GIAO) basis functions. The new implementation in the NWChem quantum chemistry package is verified by calculations of nuclear shielding constants for the heavy atoms in HX (X=F, Cl, Br, I, At) and H2X (X = O, S, Se, Te, Po), and Te chemical shifts in a number of tellurium compounds. The basis set and functional dependence of g-shifts is investigated for 14 radicals with light and heavy atoms. The problem of accurately predicting F NMR shielding in UF6-nCln, n = 1 to 6, is revisited. The results are sensitive to approximations in the density functionals, indicating a delicate balance of DFT self-interaction vs. correlation. For the uranium halides, the results with the range-separated functionals are mixed.

Aquino, Fredy W.; Govind, Niranjan; Autschbach, Jochen

2011-10-01T23:59:59.000Z

10

Subcooled flow boiling of fluorocarbons  

E-Print Network [OSTI]

A study was conducted of heat transfer and hydrodynamic behavior for subcooled flow boiling of Freon-113, one of a group of fluorocarbons suitable for use in cooling of high-power-density electronic components. Problems ...

Murphy, Richard Walter

1971-01-01T23:59:59.000Z

11

Enhanced boiling heat transfer in horizontal test bundles  

SciTech Connect (OSTI)

Two-phase flow boiling from bundles of horizontal tubes with smooth and enhanced surfaces has been investigated. Experiments were conducted in pure refrigerant R-113, pure R-11, and mixtures of R-11 and R-113 of approximately 25, 50, and 75% of R-113 by mass. Tests were conducted in two staggered tube bundles consisting of fifteen rows and five columns laid out in equilateral triangular arrays with pitch-to-diameter ratios of 1.17 and 1.5. The enhanced surfaces tested included a knurled surface (Wolverine`s Turbo-B) and a porous surface (Linde`s High Flux). Pool boiling tests were conducted for each surface so that reference values of the heat transfer coefficient could be obtained. Boiling heat transfer experiments in the tube bundles were conducted at pressures of 2 and 6 bar, heat flux values from 5 to 80 kW/m{sup 2}s, and qualities from 0% to 80%, Values of the heat transfer coefficients for the enhanced surfaces were significantly larger than for the smooth tubes and were comparable to the values obtained in pool boiling. It was found that the performance of the enhanced tubes could be predicted using the pool boiling results. The degradation in the smooth tube heat transfer coefficients obtained in fluid mixtures was found to depend on the difference between the molar concentration in the liquid and vapor.

Trewin, R.R.; Jensen, M.K.; Bergles, A.E.

1994-08-01T23:59:59.000Z

12

Exploring the limit of accuracy for density functionals based on the generalized gradient approximation: Local, global hybrid, and range-separated hybrid functionals with and without dispersion corrections  

SciTech Connect (OSTI)

The limit of accuracy for semi-empirical generalized gradient approximation (GGA) density functionals is explored by parameterizing a variety of local, global hybrid, and range-separated hybrid functionals. The training methodology employed differs from conventional approaches in 2 main ways: (1) Instead of uniformly truncating the exchange, same-spin correlation, and opposite-spin correlation functional inhomogeneity correction factors, all possible fits up to fourth order are considered, and (2) Instead of selecting the optimal functionals based solely on their training set performance, the fits are validated on an independent test set and ranked based on their overall performance on the training and test sets. The 3 different methods of accounting for exchange are trained both with and without dispersion corrections (DFT-D2 and VV10), resulting in a total of 491 508 candidate functionals. For each of the 9 functional classes considered, the results illustrate the trade-off between improved training set performance and diminished transferability. Since all 491 508 functionals are uniformly trained and tested, this methodology allows the relative strengths of each type of functional to be consistently compared and contrasted. The range-separated hybrid GGA functional paired with the VV10 nonlocal correlation functional emerges as the most accurate form for the present training and test sets, which span thermochemical energy differences, reaction barriers, and intermolecular interactions involving lighter main group elements.

Mardirossian, Narbe; Head-Gordon, Martin, E-mail: mhg@cchem.berkeley.edu [Department of Chemistry, University of California, Berkeley and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)] [Department of Chemistry, University of California, Berkeley and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

2014-05-14T23:59:59.000Z

13

Pool boiling on nano-finned surfaces  

E-Print Network [OSTI]

The effect of nano-structured surfaces on pool boiling heat transfer is explored in this study. Experiments are conducted in a cubical test chamber containing fluoroinert coolant (PF5060, Manufacturer: 3M Co.) as the working fluid. Pool boiling...

Sriraman, Sharan Ram

2009-05-15T23:59:59.000Z

14

Cold, dilute spinless particles interacting via a weak, finite-range potential: an application of asymptotic approximation of integrals in computational physics  

SciTech Connect (OSTI)

The properties of many-particle quantum systems can change drastically if the particles are attractive overall (e.g. a Fermi gas of atoms can become a Bose gas of dimers). It is therefore important to know if pairing can occur, particularly in the dilute strong coupling limit. We focus on cold helium atoms, which interact weakly via a finite-range potential. This problem can, of course, be approached numerically. However, with the extremely delicate balance of kinetic and potential energy, how do we know we can trust the number (e.g. the binding energy) that the computer produces? We could try several numerical schemes implemented with utmost care, and if they agree, we might feel confident in the answer. However, this does not constitute a proof: each scheme could be making the same mistake. We implement, instead, an analytical approach with guaranteed error bounds, which exploits an accident of Nature; namely, a small parameter in the pair wave function that invites the use of asymptotic theory. Leveraging the true long-range form of the wave function, a variational approach for bounds on the binding energy and dimer size produces integrals of a form that is well-known in the theory of asymptotic approximation of integrals. Despite being 'merely' a variational method, the upper bound obtained for the binding energy of the {sup 4}He{sub 2} dimer in three dimensions is remarkably close to a recent experimental value of 1.7 mK. Moreover, the calculated variational dimer size is also good. We have demonstrated the analytical framework by simulating the search for {sup 3}He{sub 2}, {sup 4}He{sub 2} and {sup 3}He-{sup 4}He dimers in one, two and three dimensions. The details will be published elsewhere.

Wojdylo, John [School of Physics, University of Western Australia, 35 Stirling Hwy, Crawley 6009 WA (Australia)

2010-06-15T23:59:59.000Z

15

Vapor pressure and boiling point elevation of slash pine black liquors: Predictive models with statistical approach  

SciTech Connect (OSTI)

Vapor-liquid equilibria and boiling point elevation of slash pine kraft black liquors over a wide range of solid concentrations (up to 85% solids) has been studied. The liquors are from a statistically designed pulping experiment for pulping slash pine in a pilot scale digester with four cooking variables of effective alkali, sulfidity, cooking time, and cooking temperature. It was found that boiling point elevation of black liquors is pressure dependent, and this dependency is more significant at higher solids concentrations. The boiling point elevation data at different solids contents (at a fixed pressure) were correlated to the dissolved solids (S/(1 {minus} S)) in black liquor. Due to the solubility limit of some of the salts in black liquor, a change in the slope of the boiling point elevation as a function of the dissolved solids was observed at a concentration of around 65% solids. An empirical method was developed to describe the boiling point elevation of each liquor as a function of pressure and solids mass fraction. The boiling point elevation of slash pine black liquors was correlated quantitatively to the pulping variables, using different statistical procedures. These predictive models can be applied to determine the boiling point rise (and boiling point) of slash pine black liquors at processing conditions from the knowledge of pulping variables. The results are presented, and their utility is discussed.

Zaman, A.A.; McNally, T.W.; Fricke, A.L. [Univ. of Florida, Gainesville, FL (United States)] [Univ. of Florida, Gainesville, FL (United States)

1998-01-01T23:59:59.000Z

16

Process for reforming naphthene and paraffin-containing hydrocarbons in the naphtha boiling range and isomerizing C sub 5 -C sub 6 normal paraffin feedstock to produce a high octane gasoline  

SciTech Connect (OSTI)

This patent describes a process for reforming a naphthenic and paraffin-containing hydrocarbon feedstock to produce a reformate product having an increased octane rating by contacting the feedstock with a reforming catalyst in the presence of hydrogen at reforming conditions in a reforming zone, the reforming zone including a naphtha dehydrogenation zone and a paraffin dehydrocyclization zone wherein heated, pressurized hydrogen is added to the effluent stream from the naphtha dehydrogenation zone prior to charging the effluent stream to the paraffin dehydrocyclization zone to produce a first product stream comprising a gasoline range reformate product having an RON octane rating of at least about 90 and hydrogen wherein the reformate product is separated from the hydrogen in a reformate separation zone. It comprises: charging at least a portion of the heated, pressurized hydrogen with a C{sub 5}-C{sub 6} n-paraffin feedstock to an isomerization zone containing an isomerization catalyst at isomerization conditions to produce a second product stream containing an isomerized C{sub 5}-C{sub 6} product and passing the second product stream to the reformate separation zone and recovering at least a major portion of the isomerized C{sub 5}-C{sub 6} product with the reformate product.

Dalson, M.H.

1990-05-08T23:59:59.000Z

17

Boiling Radial Flow in Fractures of Varying  

E-Print Network [OSTI]

the surface, within the matrix. The depth of boiling was a function of injection rate, thermal power supplied coupled to injection rate into the fracture. However, for porous surfaces, heat flux, and associated values of excess temperature and a boiling convection coefficient exhibited variation with injection rate

Stanford University

18

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

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

PACCAR CRADA: Experimental Investigation in Coolant Boiling in a Half-Heated Circular Tube PACCAR CRADA: Experimental Investigation in Coolant Boiling in a Half-Heated Circular...

19

CRADA with PACCAR Experimental Investigation in Coolant Boiling...  

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

PACCAR Experimental Investigation in Coolant Boiling in a Half-Heated Circular Tube CRADA with PACCAR Experimental Investigation in Coolant Boiling in a Half-Heated Circular Tube...

20

Acoustically Enhanced Boiling Heat Transfer  

E-Print Network [OSTI]

An acoustic field is used to increase the critical heat flux (CHF) of a flat-boiling-heat-transfer surface. The increase is a result of the acoustic effects on the vapor bubbles. Experiments are performed to explore the effects of an acoustic field on vapor bubbles in the vicinity of a rigid-heated wall. Work includes the construction of a novel heater used to produce a single vapor bubble of a prescribed size and at a prescribed location on a flatboiling surface for better study of an individual vapor bubble's reaction to the acoustic field. Work also includes application of the results from the single-bubble heater to a calibrated-copper heater used for quantifying the improvements in CHF.

Z. W. Douglas; M. K. Smith; A. Glezer

2008-01-07T23:59:59.000Z

Note: This page contains sample records for the topic "approximate boiling range" 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

Void volumes in subcooled boiling systems  

E-Print Network [OSTI]

Introduction: Knowledge of the pressure drop in a channel and the resulting flow redistribution is essential in predicting the performance of a nuclear reactor. The pressure drop in a channel which is experiencing boiling ...

Griffith, P.

1958-01-01T23:59:59.000Z

22

Pool boiling heat transfer characteristics of nanofluids  

E-Print Network [OSTI]

Nanofluids are engineered colloidal suspensions of nanoparticles in water, and exhibit a very significant enhancement (up to 200%) of the boiling Critical Heat Flux (CHF) at modest nanoparticle concentrations (50.1% by ...

Kim, Sung Joong, Ph. D. Massachusetts Institute of Technology

2007-01-01T23:59:59.000Z

23

Nucleate boiling bubble growth and departure  

E-Print Network [OSTI]

The vapor bubble formation on the heating surface during pool boiling has been studied experimentally. Experiments were made at the atmospheric pressure 28 psi and 40 psi, using degassed distilled water and ethanol. The ...

Staniszewski, Bogumil E.

1959-01-01T23:59:59.000Z

24

Pool boiling on nano-finned surfaces  

E-Print Network [OSTI]

is explored in this study. Experiments are conducted in a cubical test chamber containing fluoroinert coolant (PF5060, Manufacturer: 3M Co.) as the working fluid. Pool boiling experiments are conducted for saturation and subcooled conditions. Three...). .................................................................................................68 Fig. 19. Plots comparing the heat flux through the enhanced test surfaces (qw”) with the heat flux through the bare test surface (qb”) under 10 °C sub-cooling condition for both nulceate and film boiling regimes. Heat flux data...

Sriraman, Sharan Ram

2008-10-10T23:59:59.000Z

25

Boiling water reactor control rod  

SciTech Connect (OSTI)

This patent describes a control rod for a boiling water type nuclear power reactor, the improvement comprising: (a) an elongated central stem defining a longitudinally extending internal central gas plenum; (b) blades connected to and extending along and radially outward from the stem, each blade including an elongated body portion extending along the stem and terminating in an end tip portion; (c) means defining a series of internal cavities in each of the blades, the cavities being arranged in columns and rows across the length and width of the body and tip portions of the blade; (d) pellets of neutron absorbing material, each disposed within one of the cavities with each of the cavities being oversized in relation to the size of the pellet disposed therein to allow extra space for swelling of the pellet. The cavities and the pellets disposed therein are arranged to define a longer, constant worth section generally coextensive with the body portion of the blade and a shorter, reduced worth section generally coextensive with the end tip portion of the blade; and (e) means defined within each blade communicating each of the cavities with the central gas plenum for allowing any gases generated by irradiation of the pellets to expand from the cavities into the plenum.

Wilson, J.F.; Doshi, P.K.

1986-12-23T23:59:59.000Z

26

Lattice Boltzmann modeling of boiling heat transfer: The boiling curve and the effects of wettability  

E-Print Network [OSTI]

A hybrid thermal lattice Boltzmann (LB) model is presented to simulate thermal multiphase flows with phase change based on an improved pseudopotential LB approach [Q. Li, K. H. Luo, and X. J. Li, Phys. Rev. E 87, 053301 (2013)]. The present model does not suffer from the spurious term caused by the forcing-term effect, which was encountered in some previous thermal LB models for liquid-vapor phase change. Using the model, the liquid-vapor boiling process is simulated. The boiling curve together with the three boiling stages (nucleate boiling, transition boiling, and film boiling) is numerically reproduced in the LB community for the first time. The numerical results show that the basic features and the fundamental characteristics of boiling heat transfer are well captured, such as the severe fluctuation of transient heat flux in the transition boiling and the feature that the maximum heat transfer coefficient lies at a lower wall superheat than that of the maximum heat flux. Furthermore, the effects of the he...

Li, Q; Francois, M M; He, Y L; Luo, K H

2015-01-01T23:59:59.000Z

27

E-Print Network 3.0 - automatic boiling water Sample Search Results  

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

boiling water Search Powered by Explorit Topic List Advanced Search Sample search results for: automatic boiling water Page: << < 1 2 3 4 5 > >> 1 Numerical Simulation of Boiling...

28

Hydrodynamics and heat transfer during flow boiling instabilities in a single microchannel  

E-Print Network [OSTI]

Hydrodynamics and heat transfer during flow boiling instabilities in a single microchannel July 2008 Keywords: Boiling Microchannels Visualisation Flow boiling instabilities Heat transfer a b intensification heat removal. Flow boiling heat transfer in microchannel geometry and the associated flow

Aussillous, Pascale

29

The role of surface conditions in nucleate boiling  

E-Print Network [OSTI]

Nucleation from a single cavity has been stuied indicating that cavity gemtry is aportant in two ways. The mouth diameter determines the superheat nmeded to initiate boiling and its shape determines its stability one boiling ...

Griffith, P.

1958-01-01T23:59:59.000Z

30

Boiling and condensation in a liquid-filled enclosure  

E-Print Network [OSTI]

A combined experimental and analytical investigation of boiling and condensation in a liquid-filled enclosure, with water and Freon- 113 as the working fluids, is described. The operating characteristics of a boiling system, ...

Bar-Cohen Avram

1971-01-01T23:59:59.000Z

31

Exploring the Limits of Boiling and Evaporative Heat Transfer Using Micro/Nano Structures  

E-Print Network [OSTI]

using boiling heat transfer, it opens up a new direction forusing boiling heat transfer. This opens up a new direction

Lu, Ming-Chang

2010-01-01T23:59:59.000Z

32

PNNL Enhanced Pool-Boiling Heat Transfer Using Nanostructured Surfaces  

ScienceCinema (OSTI)

Close-up video of boiling taking place on a nanostructured surface in a controlled laboratory experiment.

None

2012-12-31T23:59:59.000Z

33

Boiling of nuclear liquid in the micro-canonical ensemble  

E-Print Network [OSTI]

-dependence of the nuclear symmetry energy and the critical temperature of 1 #12;Boiling of nuclear liquid in the microBoiling of nuclear liquid in the micro-canonical ensemble K. Miyazaki E-mail: miyazakiro@rio.odn.ne.jp Abstract New calculus of the liquid-gas phase transition is developed for the boiling of nuclear liquid

34

Mechanism of nucleate pool boiling heat transfer to sodium and the criterion for stable boiling  

E-Print Network [OSTI]

A comparison between liquid metals and other common fluids, like water, is made as regards to the various stages of nucleate pool boiling. It is suggested that for liquid metals the stage of building the thermal layer plays ...

Shai, Isaac

1967-01-01T23:59:59.000Z

35

Transition from film boiling to nucleate boiling in forced convection vertical flow  

E-Print Network [OSTI]

The mechanism of collapse of forced cnnvection annular vertical flow film boiling, with liquid core, is investigated using liquid nitrogen at low pressures. The report includes the effect of heat flux from the buss bar. ...

Iloeje, Onwuamaeze C.

1972-01-01T23:59:59.000Z

36

Pressure drop, heat transfer, critical heat flux, and flow stability of two-phase flow boiling of water and ethylene glycol/water mixtures - final report for project "Efficent cooling in engines with nucleate boiling."  

SciTech Connect (OSTI)

Because of its order-of-magnitude higher heat transfer rates, there is interest in using controllable two-phase nucleate boiling instead of conventional single-phase forced convection in vehicular cooling systems to remove ever increasing heat loads and to eliminate potential hot spots in engines. However, the fundamental understanding of flow boiling mechanisms of a 50/50 ethylene glycol/water mixture under engineering application conditions is still limited. In addition, it is impractical to precisely maintain the volume concentration ratio of the ethylene glycol/water mixture coolant at 50/50. Therefore, any investigation into engine coolant characteristics should include a range of volume concentration ratios around the nominal 50/50 mark. In this study, the forced convective boiling heat transfer of distilled water and ethylene glycol/water mixtures with volume concentration ratios of 40/60, 50/50, and 60/40 in a 2.98-mm-inner-diameter circular tube has been investigated in both the horizontal flow and the vertical flow. The two-phase pressure drop, the forced convective boiling heat transfer coefficient, and the critical heat flux of the test fluids were determined experimentally over a range of the mass flux, the vapor mass quality, and the inlet subcooling through a new boiling data reduction procedure that allowed the analytical calculation of the fluid boiling temperatures along the experimental test section by applying the ideal mixture assumption and the equilibrium assumption along with Raoult's law. Based on the experimental data, predictive methods for the two-phase pressure drop, the forced convective boiling heat transfer coefficient, and the critical heat flux under engine application conditions were developed. The results summarized in this final project report provide the necessary information for designing and implementing nucleate-boiling vehicular cooling systems.

Yu, W.; France, D. M.; Routbort, J. L. (Energy Systems)

2011-01-19T23:59:59.000Z

37

Boiling heat transfer in a vertical microchannel: Local estimation during flow boiling with a non intrusive method  

E-Print Network [OSTI]

Boiling heat transfer in a vertical microchannel: Local estimation during flow boiling with a non the results of experimental and numerical studies concerning boiling heat transfer inside vertical in minichannels for several gravity levels (µg, 1g, 2g). To fully understand the high heat transfer potential

38

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

39

Nonlinear dynamics and chaos in boiling water reactors  

SciTech Connect (OSTI)

There are currently 72 commercial boiling water reactors (BWRs) in operation or under construction in the western world, 37 of them in the United States. Consequently, a great effort has been devoted to the study of BWR systems under a wide range of plant operating conditions. This paper represents a contribution to this ongoing effort; its objective is to study the basic dynamic processes in BWR systems, with special emphasis on the physical interpretation of BWR dynamics. The main thrust in this work is the development of phenomenological BWR models suited for analytical studies performed in conjunction with numerical calculations. This approach leads to a deeper understanding of BWR dynamics and facilitates the interpretation of numerical results given by currently available sophisticated BWR codes. 6 refs., 14 figs., 2 tabs.

March-Leuba, J.

1988-01-01T23:59:59.000Z

40

actual coolant boiling: Topics by E-print Network  

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

. . . . 18 3.4.1 Heat Exchanger - Code description . . . . . . . . . . . . . . . 18 3.4.2 Simulation ResultsADVANCED POWER PLANT MODELING WITH APPLICATIONS TO THE ADVANCED BOILING...

Note: This page contains sample records for the topic "approximate boiling range" 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

abwr advanced boiling: Topics by E-print Network  

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

. . . . 18 3.4.1 Heat Exchanger - Code description . . . . . . . . . . . . . . . 18 3.4.2 Simulation ResultsADVANCED POWER PLANT MODELING WITH APPLICATIONS TO THE ADVANCED BOILING...

42

advanced boiling curve: Topics by E-print Network  

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

. . . . 18 3.4.1 Heat Exchanger - Code description . . . . . . . . . . . . . . . 18 3.4.2 Simulation ResultsADVANCED POWER PLANT MODELING WITH APPLICATIONS TO THE ADVANCED BOILING...

43

A TEN MEGAWATT BOILING HETEROGENEOUS PACKAGE POWER REACTOR. Reactor...  

Office of Scientific and Technical Information (OSTI)

A TEN MEGAWATT BOILING HETEROGENEOUS PACKAGE POWER REACTOR. Reactor Design and Feasibility Problem Re-direct Destination: Temp Data Fields Rosen, M. A.; Coburn, D. B.; Flynn, T....

44

A method of correlating heat transfer data for surface boiling of liquids  

E-Print Network [OSTI]

A method based an a logical uxplanation of the meani of beat transfer associated with the boiling process is presented for correlating heat transfer data for nucleate boiling of liquids for the case of pool boiling. Tbe ...

Rohsenow, Warren M.

1951-01-01T23:59:59.000Z

45

EXPERIMENTAL INVESTIGATION OF BOILING HEAT CONVECTION IN A FRACTURE  

E-Print Network [OSTI]

EXPERIMENTAL INVESTIGATION OF BOILING HEAT CONVECTION IN A FRACTURE A REPORT SUBMITTED between heat conduction and heat convection with boiling flow in a rock fracture. An experimental coefficient. This coefficient is the proportionality factor between the heat flux to a fracture surface

Stanford University

46

Little low-power boiling never hurt anybody. [LMFBR  

SciTech Connect (OSTI)

Failures in the shutdown heat removal system of an LMFBR might lead to flow stagnation and coolant boiling in the reactor core. At normal operating power, the onset of sodium boiling will lead to film dryout and melting of the cladding and fuel within a few seconds. On the other hand, both calculations and currently available experimental data indicate that at heat fluxes corresponding to decay heat power levels, boiling leads to improved heat removal; and it limits the temperature rise in the fuel pins. Therefore, when setting safety criteria for decay heat removal systems, there is no reason to preclude sodium boiling per se because of heat removal considerations. As an example that illustrates the beneficial impact of coolant boiling, a case involving temporary loss of feedwater and staggered pump failures in a hypothetical, 1000-MWe loop-type reactor was run in the SASSYS-1 code.

Dunn, F.E.

1985-01-01T23:59:59.000Z

47

Conversion of direct process high-boiling residue to monosilanes  

DOE Patents [OSTI]

A process for the production of monosilanes from the high-boiling residue resulting from the reaction of hydrogen chloride with silicon metalloid in a process typically referred to as the "direct process." The process comprises contacting a high-boiling residue resulting from the reaction of hydrogen chloride and silicon metalloid, with hydrogen gas in the presence of a catalytic amount of aluminum trichloride effective in promoting conversion of the high-boiling residue to monosilanes. The present process results in conversion of the high-boiling residue to monosilanes. At least a portion of the aluminum trichloride catalyst required for conduct of the process may be formed in situ during conduct of the direct process and isolation of the high-boiling residue.

Brinson, Jonathan Ashley (Vale of Glamorgan, GB); Crum, Bruce Robert (Madison, IN); Jarvis, Jr., Robert Frank (Midland, MI)

2000-01-01T23:59:59.000Z

48

Some investigations on the enhancement of boiling heat transfer from planer surface embedded with continuous open tunnels  

SciTech Connect (OSTI)

Boiling heat transfer from a flat surface can be enhanced if continuous open tunnel type structures are embedded in it. Further, improvement of boiling heat transfer from such surfaces has been tried by two separate avenues. At first, inclined tunnels are embedded over the solid surface and an effort is made to optimize the tunnel inclination for boiling heat transfer. Surfaces are manufactured in house with four different inclinations of the tunnels with or without a reentrant circular pocket at the end of the tunnel. Experiments conducted in the nucleate boiling regime showed that 45 deg inclination of the tunnels for both with and without base geometry provides the highest heat transfer coefficient. Next, active fluid rotation was imposed to enhance the heat transfer from tunnel type surfaces with and without the base geometry. Rotational speed imparted by mechanical stirrer was varied over a wide range. It was observed that fluid rotation enhances the heat transfer coefficient only up to a certain value of stirrer speed. Rotational speed values, beyond this limit, reduce the boiling heat transfer severely. A comparison shows that embedding continuous tunnel turns out to be a better option for the increase of heat transfer coefficient compared to the imposition of fluid rotation. But the behavior of inclined tunnels under the action of fluid rotation is yet to be established and can be treated as a future scope of the work. (author)

Das, A.K.; Das, P.K.; Saha, P. [Department of Mechanical Engineering, Indian Institute of Technology, Kharagpur 721 302 (India)

2010-11-15T23:59:59.000Z

49

Effects of surface parameters on boiling heat transfer phenomena  

E-Print Network [OSTI]

Nanofluids, engineered colloidal dispersions of nanoparticles in fluid, have been shown to enhance pool and flow boiling CHF. The CHF enhancement was due to nanoparticle deposited on the heater surface, which was verified ...

Truong, Bao H. (Bao Hoai)

2011-01-01T23:59:59.000Z

50

Suppression and Enhancement of Boiling Associated with Multiple Droplet Impingement  

E-Print Network [OSTI]

are at play simultaneously. Furthermore, experiments with single streams of droplets have not been able to elucidate the effects of the onset of boiling (ONB) during the droplet impingement process. Therefore, efforts have been undertaken to consider...

Yang, Yuxuan

2014-05-01T23:59:59.000Z

51

Pool boiling studies on nanotextured surfaces under highly subcooled conditions  

E-Print Network [OSTI]

Subcooled pool boiling on nanotextured surfaces is explored in this study. The experiments are performed in an enclosed viewing chamber. Two silicon wafers are coated with Multiwalled Carbon Nanotubes (MWCNT), 9 microns (Type-A) and 25 microns (Type...

Sathyamurthi, Vijaykumar

2009-05-15T23:59:59.000Z

52

Hydrodynamics, heat transfer and flow boiling instabilities in microchannels   

E-Print Network [OSTI]

Boiling in microchannels is a very efficient mode of heat transfer with high heat and mass transfer coefficients achieved. Less pumping power is required for two-phase flows than for single-phase liquid flows to achieve ...

Barber, Jacqueline Claire

2010-01-01T23:59:59.000Z

53

Determination of pool boiling Critical Heat Flux enhancement in nanofluids  

E-Print Network [OSTI]

Nanofluids are engineered colloids composed of nano-size particles dispersed in common fluids such as water or refrigerants. Using an electrically controlled wire heater, pool boiling Critical Heat Flux (CHF) of Alumina ...

Truong, Bao H. (Bao Hoai)

2007-01-01T23:59:59.000Z

54

Thermal boundary layer development in dispersed flow film boiling  

E-Print Network [OSTI]

Dispersed flow film boiling consists of a dispersion of droplets which are carried over a very hot surface by their vapor. This process occurs in cryogenic equipment and wet steam turbines. It is also of interest in the ...

Hull, Lawrence M.

1982-01-01T23:59:59.000Z

55

Dryout droplet distribution and dispersed flow film boiling  

E-Print Network [OSTI]

Dispersed flow film boiling is characterized by liquid-phase droplets entrained in a continuous vapor-phase flow. In a previous work at MIT, a model of dispersed flow heat transfer was developed, called the Local Conditions ...

Hill, Wayne S.

1982-01-01T23:59:59.000Z

56

The effects of surface conditions on boiling characteristics  

E-Print Network [OSTI]

A unified model relating surface variables to the nucleate pool boiling characteristics was developed. A simple vapor trapping mechanism was postulated and a geometrical model constructed for idealized conical cavities ...

Lorenz, J. J.

1972-01-01T23:59:59.000Z

57

Forced-convection, dispersed-flow film boiling  

E-Print Network [OSTI]

This report presents the latest results of an investigation of the characteristics of dispersed flow film boiling. Heat transfer data are presented for vertical upflow of nitrogen in an electrically heated tube, 0.4 in. ...

Hynek, Scott Josef

1969-01-01T23:59:59.000Z

58

Film Boiling on Downward Quenching Hemisphere of Varying Sizes  

SciTech Connect (OSTI)

Film boiling heat transfer coefficients for a downward-facing hemispherical surface are measured from the quenching tests in DELTA (Downward-boiling Experimental Laminar Transition Apparatus). Two test sections are made of copper to maintain low Biot numbers. The outer diameters of the hemispheres are 120 mm and 294 mm, respectively. The thickness of all the test sections is 30 mm. The effect of diameter on film boiling heat transfer is quantified utilizing results obtained from the test sections. The measured data are compared with the numerical predictions from laminar film boiling analysis. The measured heat transfer coefficients are found to be greater than those predicted by the conventional laminar flow theory on account of the interfacial wavy motion incurred by the Helmholtz instability. Incorporation of the wavy motion model considerably improves the agreement between the experimental and numerical results in terms of heat transfer coefficient. In addition, the interfacial wavy motion and the quenching process are visualized through a digital camera.

Chan S. Kim; Kune Y. Suh; Joy L. Rempe; Fan-Bill Cheung; Sang B. Kim

2004-04-01T23:59:59.000Z

59

Pressure drop with surface boiling in small-diameter tubes  

E-Print Network [OSTI]

Pressure drop for water flowing in small-diameter tubes under isothermal, nonboiling, and surface-boiling conditions was investigated. Experimental results for local pressure gradient and heattransfer coefficients are ...

Dr?mer, Thomas

1964-01-01T23:59:59.000Z

60

A study of boiling water flow regimes at low pressures  

E-Print Network [OSTI]

"A comprehensive experimental program to examine flow regimes at pressures below 100 psia for boiling of water in tubes was carried out. An electrical probe, which measures the resistance of the fluid between the centerline ...

Fiori, Mario P.

1966-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "approximate boiling range" 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

Infrared thermometry study of nanofluid pool boiling phenomena  

E-Print Network [OSTI]

Abstract Infrared thermometry was used to obtain first-of-a-kind, time- and space-resolved data for pool boiling phenomena in water-based nanofluids with diamond and silica nanoparticles at low concentration (<0.1 vol.%). ...

Gerardi, Craig

62

Experimental design for study of nucleate boiling in porous structures  

E-Print Network [OSTI]

The superheat required to initiate nucleate boiling inside porous wicks is not well understood in practice. This thesis reports the design of an experimental setup for investigating the onset of vapor nucleation in sintered ...

Kelley, Mitchell Joseph

2011-01-01T23:59:59.000Z

63

Model of critical heat flux in subcooled flow boiling  

E-Print Network [OSTI]

The physical phenomenon occurring before and at the critical heat flux (CHF) for subcooled flow boiling has been investigated. The first phase of this study established the basic nature of the flow structure at CHF. A ...

Fiori, Mario P.

1968-01-01T23:59:59.000Z

64

Corrosion optimized Zircaloy for boiling water reactor (BWR) fuel elements  

SciTech Connect (OSTI)

A corrosion optimized Zircaloy has to be based primarily on in-boiling water reactor (in-BWR) results. Therefore, the material parameters affecting corrosion were deduced from results of experimental fuel rod irradiation with systematic variations and from a large variety of material coupons exposed in water rods up to four cycles. The major material effects is the size and distribution of precipitates. For optimizing both early and late corrosion, the size has to stay in a small range. In the case of material quenched in the final stage, the quenching rate appears to be an important parameter. As far as materials chemistry is concerned, the in-BWR results indicate that corrosion in BWRs is influenced by the alloying elements tin, chromium, and the impurity silicon. In addition to corrosion optimization, hydriding is also considered. A large variation from lot to lot under identically coolant condition has been found. The available data indicate that the chromium content is the most important material parameter for hydrogen pickup.

Garzarolli, F.; Schumann, R.; Steinberg, E. [Siemens AG, Erlangen (Germany). Power Generation Group

1994-12-31T23:59:59.000Z

65

Sodium boiling dryout correlation for LMFBR fuel assemblies  

SciTech Connect (OSTI)

Under certain postulated accident conditions for a Liquid Metal Fast Breeder Reactor (LMFBR), such as the failure of the shutdown heat removal system (SHRS), sodium boiling and clad dryout might occur in the fuel assemblies. It is important to predict the time from boiling inception to dryout, since sustained clad dryout will result in core damage. In this paper a dryout correlation is presented. This correlation is based on 21 boiling tests which resulted in dryout from the THORS BUNDLE 6A, a 19-pin full-length simulated LMFBR fuel assembly and from the THORS Bundle 9, a 61-pin full-length simulated LMFBR fuel assembly. All these tests were performed as follows: for each specified bundle power, an initial steady-state high sodium flow was established, for which sodium boiling did not occur in the bundle. The temperature at the outlet of the test section was approx. 700/sup 0/C. Then, using a programmable pump control system, the flow was reduced to a low value and boiling occurred.

Carbajo, J.J.; Rose, S.D.

1984-01-01T23:59:59.000Z

66

Verified integrity properties for safe approximate program transformations  

E-Print Network [OSTI]

Approximate computations (for example, video, audio, and image processing, machine learning, and many scientific computations) have the freedom to generate a range of acceptable results. Approximate program transformations ...

Kim, Deokhwan

67

Technology, safety and costs of decommissioning a Reference Boiling Water Reactor Power Station. Main report. Volume 1  

SciTech Connect (OSTI)

Technology, safety and cost information is given for the conceptual decommissioning of a large (1100MWe) boiling water reactor (BWR) power station. Three approaches to decommissioning, immediate dismantlement, safe storage with deferred dismantlement and entombment, were studied to obtain comparisons between costs, occupational radiation doses, potential dose to the public and other safety impacts. It also shows the sensitivity of decommissioning safety and costs to the power rating of a BWR in the range of 200 to 1100 MWe.

Oak, H.D.; Holter, G.M.; Kennedy, W.E. Jr.; Konzek, G.J.

1980-06-01T23:59:59.000Z

68

Pool boiling heat transfer enhancement over cylindrical tubes with water at atmospheric pressure, Part I: Experimental results  

E-Print Network [OSTI]

Pool boiling heat transfer enhancement over cylindrical tubes with water at atmospheric pressure online 4 May 2013 Keywords: Pool boiling Heat transfer enhancement Open microchannels Cylindrical tube boiling heat transfer over enhanced cylindrical microchannel test surfaces with water at atmospheric

Kandlikar, Satish

69

Fast Approximate Convex Decomposition  

E-Print Network [OSTI]

Approximate convex decomposition (ACD) is a technique that partitions an input object into "approximately convex" components. Decomposition into approximately convex pieces is both more efficient to compute than exact convex decomposition and can...

Ghosh, Mukulika

2012-10-19T23:59:59.000Z

70

Mechanism and behavior of nucleate boiling heat transfer to the alkalai liquid metals  

E-Print Network [OSTI]

A model of boiling heat transfer to the alkali liquid metals is postulated from an examination of the events and phases of the nucleate boiling cycle. The model includes the important effect of microlayer evaporation which ...

Deane, Charles William

1969-01-01T23:59:59.000Z

71

Alumina Nanoparticle Pre-coated Tubing Ehancing Subcooled Flow Boiling Cricital Heat Flux  

E-Print Network [OSTI]

Nanofluids are engineered colloidal dispersions of nano-sized particle in common base fluids. Previous pool boiling studies have shown that nanofluids can improve critical heat flux (CHF) up to 200% for pool boiling and ...

Truong, Bao H.

72

E-Print Network 3.0 - advanced boiling water Sample Search Results  

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

water Search Powered by Explorit Topic List Advanced Search Sample search results for: advanced boiling water Page: << < 1 2 3 4 5 > >> 1 Boiling Radial Flow in Fractures of...

73

Forced-convection surface-boiling heat transfer and burnout in tubes of small diameters  

E-Print Network [OSTI]

A basic heat-transfer apparatus was designed and constructed for the study of forced-convection boiling in small channels. The various regions of forced-convection surface boiling were studied experimentally and analytically. ...

Bergles A. E.

1962-01-01T23:59:59.000Z

74

Measurement of Nucleate Pool Boiling with Synchronized Particle Imaging Velocimetry and Infrared Thermometry  

E-Print Network [OSTI]

Nucleate boiling is important in many energy systems including light water reactors. Currently significant efforts are underway to develop mechanisticmodels for nucleate boiling based on computational fluid dynamics (CFD). ...

Duan, X.

75

Acoustic emission feedback control for control of boiling in a microwave oven  

DOE Patents [OSTI]

An acoustic emission based feedback system for controlling the boiling level of a liquid medium in a microwave oven is provided. The acoustic emissions from the medium correlated with surface boiling is used to generate a feedback control signal proportional to the level of boiling of the medium. This signal is applied to a power controller to automatically and continuoulsly vary the power applied to the oven to control the boiling at a selected level.

White, Terry L. (Oak Ridge, TN)

1991-01-01T23:59:59.000Z

76

Numerical study of high heat ux pool boiling heat transfer Ying He a,*, Masahiro Shoji b  

E-Print Network [OSTI]

Numerical study of high heat ¯ux pool boiling heat transfer Ying He a,*, Masahiro Shoji b , Shigeo simulation model of boiling heat transfer is proposed based on a numerical macrolayer model [S. Maruyama, M. Shoji, S. Shimizu, A numerical simulation of transition boiling heat transfer, in: Proceedings

Maruyama, Shigeo

77

Flow Boiling Heat Transfer Coefficient In Minichannels Correlation and Trends Satish G. Kandlikar  

E-Print Network [OSTI]

Flow Boiling Heat Transfer Coefficient In Minichannels ­ Correlation and Trends Satish G. Kandlikar York 14623, USA The flow boiling heat transfer in small diameter passages is being applied in many boiling heat transfer coefficient with the correlations developed for conventional channels. It is found

Kandlikar, Satish

78

NUMERICAL SIMULATION OF POOL BOILING FOR STEADY STATE AND TRANSIENT HEATING  

E-Print Network [OSTI]

1 NUMERICAL SIMULATION OF POOL BOILING FOR STEADY STATE AND TRANSIENT HEATING Ying He, Masahiro role in nucleate and transition boiling heat transfer at high heat flux. Many experiments have been in the numerical simulation of boiling heat transfer. In this study, based on the macrolayer evaporation model

Maruyama, Shigeo

79

Enhancement of Pool Boiling Heat Transfer in Confined Space  

E-Print Network [OSTI]

on pool boiling. In the study, confinement was achieved by placing a flat plate over heated surface. The flat plate has a hole in the middle, and there is a gap between the flat plate and the heater. The diameters of hole are 2 mm, 3 mm, and 4 mm; the gap...

Hsu, Chia-Hsiang

2014-05-05T23:59:59.000Z

80

LIQUID PROPANE GAS (LPG) STORAGE AREA BOILING LIQUID EXPANDING VAPOR EXPLOSION (BLEVE) ANALYSIS  

SciTech Connect (OSTI)

The PHA and the FHAs for the SWOC MDSA (HNF-14741) identified multiple accident scenarios in which vehicles powered by flammable gases (e.g., propane), or combustible or flammable liquids (e.g., gasoline, LPG) are involved in accidents that result in an unconfined vapor cloud explosion (UVCE) or in a boiling liquid expanding vapor explosion (BLEVE), respectively. These accident scenarios are binned in the Bridge document as FIR-9 scenarios. They are postulated to occur in any of the MDSA facilities. The LPG storage area will be in the southeast corner of CWC that is relatively remote from store distaged MAR. The location is approximately 30 feet south of MO-289 and 250 feet east of 2401-W by CWC Gate 10 in a large staging area for unused pallets and equipment.

PACE, M.E.

2004-01-13T23:59:59.000Z

Note: This page contains sample records for the topic "approximate boiling range" 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

Boiling water reactor control rod programming using heuristic and mathematical methods  

SciTech Connect (OSTI)

OPROD, a computer code for automatic generation of control rod programming that has successfully been applied to an older boiling water reactor (BWR), has experienced some difficulties when applied to a BWR of larger power density and stronger heterogeneity. To improve the performance, a heuristic algorithm that is derived from accumulated experience has been introduced to search for a feasible rod pattern that satisfies all constraints. Application of this algorithm to an initial cycle of an 800-MW(e) BWR of high heterogeneity has been very successful. It has been demonstrated that the proposed algorithm is capable of finding a feasible rod pattern, even starting from an all-rods-out pattern. Some improvement was also made in the method of approximation programming (MAP) algorithm. The temporal constraint relaxation method is shown to be effective in finding an optimal control rod pattern in MAP starting from a guess pattern that is not feasible.

Hayase, T.; Motoda, H.

1980-04-01T23:59:59.000Z

82

Modeling acid-gas generation from boiling chloride brines  

SciTech Connect (OSTI)

This study investigates the generation of HCl and other acid gases from boiling calcium chloride dominated waters at atmospheric pressure, primarily using numerical modeling. The main focus of this investigation relates to the long-term geologic disposal of nuclear waste at Yucca Mountain, Nevada, where pore waters around waste-emplacement tunnels are expected to undergo boiling and evaporative concentration as a result of the heat released by spent nuclear fuel. Processes that are modeled include boiling of highly concentrated solutions, gas transport, and gas condensation accompanied by the dissociation of acid gases, causing low-pH condensate. Simple calculations are first carried out to evaluate condensate pH as a function of HCl gas fugacity and condensed water fraction for a vapor equilibrated with saturated calcium chloride brine at 50-150 C and 1 bar. The distillation of a calcium-chloride-dominated brine is then simulated with a reactive transport model using a brine composition representative of partially evaporated calcium-rich pore waters at Yucca Mountain. Results show a significant increase in boiling temperature from evaporative concentration, as well as low pH in condensates, particularly for dynamic systems where partial condensation takes place, which result in enrichment of HCl in condensates. These results are in qualitative agreement with experimental data from other studies. The combination of reactive transport with multicomponent brine chemistry to study evaporation, boiling, and the potential for acid gas generation at the proposed Yucca Mountain repository is seen as an improvement relative to previously applied simpler batch evaporation models. This approach allows the evaluation of thermal, hydrological, and chemical (THC) processes in a coupled manner, and modeling of settings much more relevant to actual field conditions than the distillation experiment considered. The actual and modeled distillation experiments do not represent expected conditions in an emplacement drift, but nevertheless illustrate the potential for acid-gas generation at moderate temperatures (<150 C).

Zhang, Guoxiang; Spycher, Nicolas; Sonnenthal, Eric; Steefel, Carl

2009-11-16T23:59:59.000Z

83

Great Boiling Springs Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy Resources Jump to: navigation,Ohio: EnergyGrasslands Renewable Energy LLCGray,Boiling Springs Geothermal

84

Knowledge and abilities catalog for nuclear power plant operators: boiling water reactors  

SciTech Connect (OSTI)

The Knowledge and Abilities Catalog for Nuclear Power Plant Operators: Boiling-Water Reactors (BWR) (NUREG-1123) provides the basis for the development of content-valid licensing examinations for reactor operators (ROs) and senior reactor operators (SROs). The examinations developed using the BWR Catalog and Examiners' Handbook for Developing Operator Licensing Examinations (NUREG-1121) will cover those topics listed under Title 10, Code of Federal Regulations, Part 55. The BWR Catalog contains approximately 7000 knowledge and ability (K/A) statements for ROs and SROs at boiling water reactors. Each K/A statement has been rated for its importance to the safe operation of the plant in a manner ensuring personnel and public health and safety. The BWR K/A Catalog is organized into five major sections: Plant-wide Generic Knowledge and Ability Statements, Plant Systems grouped by Safety Function, Emergency and Abnormal Plant Evolutions, Components, and Theory. The BWR Catalog represents a modification of the form and content of the K/A Catalog for Nuclear Power Plant Operators: Pressurized Water Reactors (NUREG-1122). First, categories of knowledge and ability statements have been redefined. Second, the scope of the definition of emergency and abnormal plant evolutions has been revised in line with a symptom-based approach. Third, K/As related to the operational applications of theory have been incorporated into the delineations for both plant systems and emergency and abnormal plant evolutions, while K/As pertaining to theory fundamental to plant operation have been delineated in a separate theory section. Finally, the components section has been revised.

Not Available

1986-09-01T23:59:59.000Z

85

Approximation of Stochastic Process  

E-Print Network [OSTI]

May 8, 2012 ... The approximation of stochastic processes by trees is an important topic in ... process ? is replaced by a finitely valued stochastic scenario ...

Alois Pichler

2012-05-08T23:59:59.000Z

86

Knowledge and abilities catalog for nuclear power plant operators: Boiling water reactors, Revision 1  

SciTech Connect (OSTI)

The Knowledge and Abilities Catalog for Nuclear Power Plant Operators: Boiling-Water Reactors (BWRs) (NUREG-1123, Revision 1) provides the basis for the development of content-valid licensing examinations for reactor operators (ROs) and senior reactor operators (SROs). The examinations developed using the BWR Catalog along with the Operator Licensing Examiner Standards (NUREG-1021) and the Examiner`s Handbook for Developing Operator Licensing Written Examinations (NUREG/BR-0122), will cover the topics listed under Title 10, Code of Federal Regulations, Part 55 (10 CFR 55). The BWR Catalog contains approximately 7,000 knowledge and ability (K/A) statements for ROs and SROs at BWRs. The catalog is organized into six major sections: Organization of the Catalog, Generic Knowledge and Ability Statements, Plant Systems grouped by Safety Functions, Emergency and Abnormal Plant Evolutions, Components, and Theory. Revision 1 to the BWR Catalog represents a modification in form and content of the original catalog. The K/As were linked to their applicable 10 CFR 55 item numbers. SRO level K/As were identified by 10 CFR 55.43 item numbers. The plant-wide generic and system generic K/As were combined in one section with approximately one hundred new K/As. Component Cooling Water and Instrument Air Systems were added to the Systems Section. Finally, High Containment Hydrogen Concentration and Plant Fire On Site evolutions added to the Emergency and Abnormal Plant Evolutions section.

NONE

1995-08-01T23:59:59.000Z

87

CASL-U-2015-0040-000 Initial Boiling Water  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed New Substation Sites Proposed Route Segments (notCAMDL20-000 Initial Boiling Water

88

Technology, safety and costs of decommissioning a reference boiling water reactor power station. Volume 1. Main report. Technical report, September 1977-October 1979  

SciTech Connect (OSTI)

Technology, safety and cost information is given for the conceptual decommissioning of a large (1100MWe) boiling water reactor (BWR) power station. Three approaches to decommissioning, immediate dismantlement, safe storage with deferred dismantlement and entombment, were studied to obtain comparisons between costs, occupational radiation doses, potential dose to the public and other safety impacts. It also shows the sensitivity of decommissioning safety and costs to the power rating of a BWR in the range of 200 to 1100 MWE.

Oak, H.D.; Holter, G.M.; Kennedy, W.E. Jr.; Konzek, G.J.

1980-06-01T23:59:59.000Z

89

Lattice Boltzmann Methods to Address Fundamental Boiling and Two-Phase Problems  

SciTech Connect (OSTI)

This report presents the progress made during the fourth (no cost extension) year of this three-year grant aimed at the development of a consistent Lattice Boltzmann formulation for boiling and two-phase flows. During the first year, a consistent LBM formulation for the simulation of a two-phase water-steam system was developed. Results of initial model validation in a range of thermo-dynamic conditions typical for Boiling Water Reactors (BWRs) were shown. Progress was made on several fronts during the second year. Most important of these included the simulation of the coalescence of two bubbles including the surface tension effects. Work during the third year focused on the development of a new lattice Boltzmann model, called the artificial interface lattice Boltzmann model (AILB model) for the 3 simulation of two-phase dynamics. The model is based on the principle of free energy minimization and invokes the Gibbs-Duhem equation in the formulation of non-ideal forcing function. This was reported in detail in the last progress report. Part of the efforts during the last (no-cost extension) year were focused on developing a parallel capability for the 2D as well as for the 3D codes developed in this project. This will be reported in the final report. Here we report the work carried out on testing the AILB model for conditions including the thermal effects. A simplified thermal LB model, based on the thermal energy distribution approach, was developed. The simplifications are made after neglecting the viscous heat dissipation and the work done by pressure in the original thermal energy distribution model. Details of the model are presented here, followed by a discussion of the boundary conditions, and then results for some two-phase thermal problems.

Rizwan Uddin

2012-01-01T23:59:59.000Z

90

Water inventory management in condenser pool of boiling water reactor  

DOE Patents [OSTI]

An improved system for managing the water inventory in the condenser pool of a boiling water reactor has means for raising the level of the upper surface of the condenser pool water without adding water to the isolation pool. A tank filled with water is installed in a chamber of the condenser pool. The water-filled tank contains one or more holes or openings at its lowermost periphery and is connected via piping and a passive-type valve (e.g., squib valve) to a high-pressure gas-charged pneumatic tank of appropriate volume. The valve is normally closed, but can be opened at an appropriate time following a loss-of-coolant accident. When the valve opens, high-pressure gas inside the pneumatic tank is released to flow passively through the piping to pressurize the interior of the water-filled tank. In so doing, the initial water contents of the tank are expelled through the openings, causing the water level in the condenser pool to rise. This increases the volume of water available to be boiled off by heat conducted from the passive containment cooling heat exchangers. 4 figs.

Gluntz, D.M.

1996-03-12T23:59:59.000Z

91

Water inventory management in condenser pool of boiling water reactor  

DOE Patents [OSTI]

An improved system for managing the water inventory in the condenser pool of a boiling water reactor has means for raising the level of the upper surface of the condenser pool water without adding water to the isolation pool. A tank filled with water is installed in a chamber of the condenser pool. The water-filled tank contains one or more holes or openings at its lowermost periphery and is connected via piping and a passive-type valve (e.g., squib valve) to a high-pressure gas-charged pneumatic tank of appropriate volume. The valve is normally closed, but can be opened at an appropriate time following a loss-of-coolant accident. When the valve opens, high-pressure gas inside the pneumatic tank is released to flow passively through the piping to pressurize the interior of the water-filled tank. In so doing, the initial water contents of the tank are expelled through the openings, causing the water level in the condenser pool to rise. This increases the volume of water available to be boiled off by heat conducted from the passive containment cooling heat exchangers. 4 figs.

Gluntz, Douglas M. (San Jose, CA)

1996-01-01T23:59:59.000Z

92

Boiling water neutronic reactor incorporating a process inherent safety design  

DOE Patents [OSTI]

A boiling-water reactor core is positioned within a prestressed concrete reactor vessel of a size which will hold a supply of coolant water sufficient to submerge and cool the reactor core by boiling for a period of at least one week after shutdown. Separate volumes of hot, clean (non-borated) water for cooling during normal operation and cool highly borated water for emergency cooling and reactor shutdown are separated by an insulated wall during normal reactor operation with contact between the two water volumes being maintained at interfaces near the top and bottom ends of the reactor vessel. Means are provided for balancing the pressure of the two volumes at the lower interface zone during normal operation to prevent entry of the cool borated water into the reactor core region, for detecting the onset of excessive power to coolant flow conditions in the reactor core and for detecting low water levels of reactor coolant. Cool borated water is permitted to flow into the reactor core when low reactor coolant levels or excessive power to coolant flow conditions are encountered.

Forsberg, Charles W. (Kingston, TN)

1987-01-01T23:59:59.000Z

93

Boiling water neutronic reactor incorporating a process inherent safety design  

DOE Patents [OSTI]

A boiling-water reactor core is positioned within a prestressed concrete reactor vessel of a size which will hold a supply of coolant water sufficient to submerge and cool the reactor core by boiling for a period of at least one week after shutdown. Separate volumes of hot, clean (nonborated) water for cooling during normal operation and cool highly borated water for emergency cooling and reactor shutdown are separated by an insulated wall during normal reactor operation with contact between the two water volumes being maintained at interfaces near the top and bottom ends of the reactor vessel. Means are provided for balancing the pressure of the two water volumes at the lower interface zone during normal operation to prevent entry of the cool borated water into the reactor core region, for detecting the onset of excessive power to coolant flow conditions in the reactor core and for detecting low water levels of reactor coolant. Cool borated water is permitted to flow into the reactor core when low reactor coolant levels or excessive power to coolant flow conditions are encountered.

Forsberg, C.W.

1985-02-19T23:59:59.000Z

94

Hypothetical Thermodynamic Properties: The Boiling and Critical Temperatures of Polyethylene and Polytetrafluoroethylene  

E-Print Network [OSTI]

Hypothetical Thermodynamic Properties: The Boiling and Critical Temperatures of Polyethylene value asymptotically approaches TB() ) (1217 ( 246) K for series related to polyethylene by the melting temperature of polyethylene.4,5 In this article, the question of whether the normal boiling tem

Chickos, James S.

95

Comparison of thorium-based fuels with different fissile components in existing boiling water reactors  

E-Print Network [OSTI]

Comparison of thorium-based fuels with different fissile components in existing boiling water, SE-412 96 Göteborg, Sweden Keywords: Thorium BWR Neutronics a b s t r a c t With the aim of investigating the technical feasibility of fuelling a conventional BWR (Boiling Water Reactor) with thorium

Demazière, Christophe

96

Boiling Crisis as a Non-Equilibrium Drying V. S. Nikolayev, D. A. Beysens, J. Hegseth  

E-Print Network [OSTI]

crisis is the formation of a vapor film between the heater and the liquid when the heat supply exceeds in the coordinates heat supply ­ heater temperature is sketched in Fig. 1 for the case of stationary boiling experiment, the so called "pool boiling". When the heat supply to the fluid pool is small, only a fluid

Nikolayev, Vadim S.

97

Effect of surface conditions on boiling heat transfer of refrigerants in shell-and-tube evaporators  

SciTech Connect (OSTI)

Experimental results are presented for the boiling heat transfer performance of R 22 and R 717 on surfaces with porous metallized coatings. A calculational-theoretical model is given for predicting the heat transfer of refrigerants boiling on a bundle of finned tubes.

Danilova, G.N.; Dyundin, V.A.; Borishanskaya, A.V.; Soloviyov, A.G.; Vol'nykh, Y.A.; Kozyrev, A.A.

1990-01-01T23:59:59.000Z

98

A Review Of Recent Progress On Nano/micro Scale Nucleate Boiling Fundamentals  

E-Print Network [OSTI]

Recent research progress in the area of nano/micro scale nucleate boiling is reviewed and an up-to-date summary is provided with a focus on the advances of fundamental boiling physics. This review examines nano/micro scale ...

Chung, J. N.

2011-01-01T23:59:59.000Z

99

Effects of Carbon Nanotube Coating on Bubble Departure Diameter and Frequency in Pool Boiling on a Flat, Horizontal Heater  

E-Print Network [OSTI]

The effects of a carbon nanotube (CNT) coating on bubble departure diameter and frequency in pool boiling experiments was investigated and compared to those on a bare silicon wafer. The pool boiling experiments were performed at liquid subcooling...

Glenn, Stephen T.

2011-08-08T23:59:59.000Z

100

Complete Numerical Simulation of Subcooled Flow Boiling in the Presence of Thermal and Chemical Interactions  

SciTech Connect (OSTI)

At present, guidelines for fuel cycle designs to prevent axial offset anomalies (AOA) in pressurized water reactor (PWR) cores are based on empirical data from several operating reactors. Although the guidelines provide an ad-hoc solution to the problem, a unified approach based on simultaneous modeling of thermal-hydraulics, chemical, and nuclear interactions with vapor generation at the fuel cladding surface does not exist. As a result, the fuel designs are overly constrained with a resulting economic penalty. The objective of present project is to develop a numerical simulation model supported by laboratory experiments that can be used for fuel cycle design with respect to thermal duty of the fuel to avoid economic penalty, as well as, AOA. At first, two-dimensional numerical simulation of the growth and departure of a bubble in pool boiling with chemical interaction is considered. A finite difference scheme is used to solve the equations governing conservation of mass, momentum, energy, and species concentration. The Level Set method is used to capture the evolving liquid-vapor interface. A dilute aqueous boron solution is considered in the simulation. From numerical simulations, the dynamic change in concentration distribution of boron during the bubble growth shows that the precipitation of boron can occur near the advancing and receding liquid-vapor interface when the ambient boron concentration level is 3,000 ppm by weight. Secondly, a complete three-dimensional numerical simulation of inception, growth and departure of a single bubble subjected to forced flow parallel to the heater surface was developed. Experiments on a flat plate heater with water and with boron dissolved in the water were carried out. The heater was made out of well-polished silicon wafer. Numbers of nucleation sites and their locations were well controlled. Bubble dynamics in great details on an isolated nucleation site were obtained while varying the wall superheat, liquid subcooling and flow velocity parametrically. Concentration variation of boron near the liquid-vapor interface was detected successfully with a newly developed miniature concentration sensor. The measured concentration variations at different radial locations from the center of cavity have the same trend as given by the numerical simulations. The deposition of boron was found near the nucleation site on the heater surface, which validates the numerical simulation. Subcooled flow boiling experiments at three pressures were performed on a nine-rod bundle with water and with boron dissolved in the water. The test runs were conducted with a wide range of mass fluxes (186 to 2800 kg/m2s) and heat fluxes (1.0 to 30.0 W/ cm2). Not only the variables required to develop mechanistic models for subcooled flow boiling were measured, but also the crud formation during boiling and its effect on the heat transfer process were investigated. (B204)

V.K. Dhir

2003-04-28T23:59:59.000Z

Note: This page contains sample records for the topic "approximate boiling range" 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

Two-phase flow visualization in a transparent, atmospheric pressure, boiling water loop  

SciTech Connect (OSTI)

The Simulant Boiling Flow Visualization (SBFV) loop, a transparent, atmospheric pressure test apparatus employing boiling water as a simulant for boiling liquid sodium, has been designed and operated at Oak Ridge National Laboratory. The objective of testing in this loop has been to study two-phase flow behavior that is phenomenologically similar to that observed in sodium boiling experiments, as part of the US Department of Energy Breeder Reactor Safety Program. A detailed description of the design of the SBFV loop is presented, as well as experimental results that show the similarity between low-power boiling behavior in water and liquid sodium. Future tests are planned in a seven-pin flow visualization bundle that will be installed in the SBFV loop. The design of this bundle is also discussed.

Levin, A.E.; Carbajo, J.J.; Montgomery, B.H.; Wantland, J.L.

1985-01-01T23:59:59.000Z

102

Two-dimensional modeling of sodium boiling in a simulated LMFBR loss-of-flow test  

SciTech Connect (OSTI)

Loss-of-flow (LOF) accidents are of major importance in LMFBR safety. Tests have been performed to simulate the simultaneous failure of all primary pumps and reactor shutdown systems in a 37-pin electrically heated test bundle installed in the KNS sodium boiling loop at the Institute of Reactor Development, Karlsruhe. The tests simulated LOF conditions of the German prototype LMFBR, the SNR 300. The main objectives of these tests were to characterize the transient boiling development to cladding dryout and to provide data for validation of sodium boiling codes. One particular LOF test, designated L22, at full power was selected as a benchmark exercise for comparison of several codes at the Eleventh Meeting of the Liquid Metal Boiling Working Group (LMBWG) held in Grenoble, France, in October 1984. In this paper, the results of the calculations performed at ORNL with the two-dimensional (2-D) boiling code THORAX are presented.

Rose, S.D.

1984-01-01T23:59:59.000Z

103

Metallurgical failure analysis of a propane tank boiling liquid expanding vapor explosion (BLEVE).  

SciTech Connect (OSTI)

A severe fire and explosion occurred at a propane storage yard in Truth or Consequences, N.M., when a truck ran into the pumping and plumbing system beneath a large propane tank. The storage tank emptied when the liquid-phase excess flow valve tore out of the tank. The ensuing fire engulfed several propane delivery trucks, causing one of them to explode. A series of elevated-temperature stress-rupture tears developed along the top of a 9800 L (2600 gal) truck-mounted tank as it was heated by the fire. Unstable fracture then occurred suddenly along the length of the tank and around both end caps, along the girth welds connecting the end caps to the center portion of the tank. The remaining contents of the tank were suddenly released, aerosolized, and combusted, creating a powerful boiling liquid expanding vapor explosion (BLEVE). Based on metallography of the tank pieces, the approximate tank temperature at the onset of the BLEVE was determined. Metallurgical analysis of the ruptured tank also permitted several hypotheses regarding BLEVE mechanisms to be evaluated. Suggestions are made for additional work that could provide improved predictive capabilities regarding BLEVEs and for methods to decrease the susceptibility of propane tanks to BLEVEs.

Kilgo, Alice C.; Eckelmeyer, Kenneth Hall; Susan, Donald Francis

2005-01-01T23:59:59.000Z

104

Transient queueing approximations for computer networks  

E-Print Network [OSTI]

for just the mean. Rothkopf/Oren's and Chang/Wang's methods obtained mean and variance values, and Clark's method produced several quantities which were used to find mean and variance statistics. For the M/M/1 case, the approximations by Gark and Chang... were very ac- curate over a wide range of input patterns and initial conditions. Rothkopf's was accurate over sll conditions but never as accurate as Chang or Clark. Johnston's and Rider's approximations performed acceptably only over some...

Baker, William A.

1986-01-01T23:59:59.000Z

105

Feasibility study on the thorium fueled boiling water breeder reactor  

SciTech Connect (OSTI)

The feasibility of (Th,U)O 2 fueled, boiling water breeder reactor based on conventional BWR technology has been studied. In order to determine the potential use of water cooled thorium reactor as a competitive breeder, this study evaluated criticality, breeding and void reactivity coefficient in response to changes made in MFR and fissile enrichments. The result of the study shows that while using light water as moderator, low moderator to fuel volume ratio (MFR=0.5), it was possible to breed fissile fuel in negative void reactivity condition. However the burnup value was lower than the value of the current LWR. On the other hand, heavy water cooled reactor shows relatively wider feasible breeding region, which lead into possibility of designing a core having better neutronic and economic performance than light water with negative void reactivity coefficient. (authors)

PetrusTakaki, N. [Dept. of Applied Science, Tokai Univ., Kitakaname, Hiratsuka, Kanagawa 259-1292 (Japan)

2012-07-01T23:59:59.000Z

106

Nucleate boiling pressure drop in an annulus: Book 2  

SciTech Connect (OSTI)

The application of the work described in this report is the production reactors at the Savannah River Site, and the context is nuclear reactor safety. The Loss of Coolant Accident (LOCA) scenario considered involves a double-ended break of a primary coolant pipe in the reactor. During a LOCA, the flow through portions of the reactor may reverse direction or be greatly reduced, depending upon the location of the break. The reduced flow rate of coolant (D{sub 2}O) through the fuel assembly channels of the reactor -- downflow in this situation -- can lead to boiling and to the potential for flow instabilities which may cause some of the fuel assembly channels to overheat and melt. That situation is to be avoided. The experimental approach is to provide a test annulus which simulates geometry, materials, and flow conditions in a Mark-22 fuel assembly (Coolant Channel 3) to the extent possible. The annulus has a full-scale geometry, and in fat uses SRL dummy hardware for the inner annulus wall in the ribbed geometry. The materials aluminum. The annulus is uniformly heated in the axial direction, but the circumferential heat flux can be varied to provide ``power tilt`` or asymmetric heating of the inner and outer annulus walls. The test facility uses H{sub 2}O rather than D{sub 2}O, but it includes the effects of dissolved helium gas present in the reactor. The key analysis approaches are: To compare the minima in the measured demand curves with analytical criteria, in particular the Saha-Zuber (1974) model; and to compare the pressure and temperature as a function of length in the annulus with an integral model for flow boiling in a heated channel. Nineteen test series and a total of 178 tests were performed. Testing addressed the effects of: Heat flux; pressure; helium gas; power tilt; ribs; asymmetric heat flux.

Block, J.A.; Crowley, C.; Dolan, F.X.; Sam, R.G.; Stoedefalke, B.H.

1992-11-01T23:59:59.000Z

107

CORQUENCH: A model for gas sparging-enhanced melt-water, film boiling heat transfer  

SciTech Connect (OSTI)

A phenomenological model (CORQUENCH) has been developed to describe the gas-sparging enhanced film boiling heat transfer between a molten pool of corium and an overlying water layer. The model accounts for thermal radiation across the vapor film, bulk liquid subcooling, interfacial area enhancement due to sparging gas, and melt entrainment into the overlying water layer. In this paper, the modeling approach is described, and a comparison with the lead-Freon 11 and lead-water film boiling experiment data of Greene is made. Predictions are then made for the case of film boiling over corium in the presence of sparging concrete decomposition gases. 15 refs., 3 figs.

Farmer, M.T.; Sienicki, J.J.; Spencer, B.W.

1990-01-01T23:59:59.000Z

108

Steady-state film-boiling data in rod-bundle geometry and non-equilibrium correlation assessment  

SciTech Connect (OSTI)

A series of 22 steady-state, rod bundle, dispersed flow film boiling experiments has been performed in the Thermal-Hydraulic Test Facility (THTF), a pressurized-water loop containing 64 full-length electrically heated rods. Test parameters in the upflow experiments cover a wide range of conditions typical of those which might be encountered during a nuclear reactor loss-of-coolant accident. Local equilibrium fluid conditions were calculated using mass and energy conservation considerations. Experimentally determined heat transfer coefficients were compared to several available film boiling heat transfer correlations: Dougall-Rohsenow, Groeneveld 5.7, Groeneveld-Delorme, Chen, Jones-Zuber, and Yoder-Rohsenow. The Groeneveld 5.7 correlation tended to predict the data better than any other correlation tested. The Dougall-Rohsenow correlation tends to overpredict the data while the Yoder-Rohsenow correlation predicted the data better than the other nonequilibrium correlations examined. However, all of the nonequilibrium correlations generally underpredict the heat transfer.

Yoder, G.L.; Morris, D.G.; Mullins, C.B.; Ott, L.J.; Reed, D.A.

1982-01-01T23:59:59.000Z

109

Development of a model to predict flow oscillations in low-flow sodium boiling  

E-Print Network [OSTI]

An experimental and analytical program has been carried out in order to better understand the cause and effect of flow oscillations in boiling sodium systems. These oscillations have been noted in previous experiments with ...

Levin, Alan Edward

1980-01-01T23:59:59.000Z

110

Prediction of departure from nucleate boiling in PWR fast power transients  

E-Print Network [OSTI]

An assessment is conducted of the differences in predicted results between use of steady state versus transient Departure from Nucleate Boiling (DNB) models, for fast power transients under forced convective heat exchange ...

Lenci, Giancarlo

2013-01-01T23:59:59.000Z

111

Nano-engineering the boiling surface for optimal heat transfer rate and critical heat flux  

E-Print Network [OSTI]

The effects on pool boiling characteristics such as critical heat flux and the heat transfer coefficient of different surface characteristics such as surface wettability, roughness, morphology, and porosity are not well ...

Phillips, Bren Andrew

2011-01-01T23:59:59.000Z

112

Conceptual design of an annular-fueled superheat boiling water reactor  

E-Print Network [OSTI]

The conceptual design of an annular-fueled superheat boiling water reactor (ASBWR) is outlined. The proposed design, ASBWR, combines the boiler and superheater regions into one fuel assembly. This ensures good neutron ...

Ko, Yu-Chih, Ph. D. Massachusetts Institute of Technology

2011-01-01T23:59:59.000Z

113

A visualization comparison of convective flow boiling heat transfer augmentation devices  

E-Print Network [OSTI]

The qualitative effects of inset-table heat transfer phics. augmentation devices on vertical in-tube convective flow boiling flow regimes, transition mechanisms, and heat transfer are presented in this study. Three twisted tapes with twist ratios...

Lundy, Brian Franklin

1998-01-01T23:59:59.000Z

114

Experimental Observation and Measurements of Pool Boiling Heat Transfer using PIV, Shadowgraphy, RICM Techniques  

E-Print Network [OSTI]

This present study seeks to contribute detailed visualization data on a pool boiling experiments using HFE-7000. Particle Image Velocimetry (PIV) was used to measure the time resolved whole field liquid velocity. Bubble dynamic parameters...

Di, Yuan 1988-

2012-12-05T23:59:59.000Z

115

Visualization of flow boiling in an annular heat exchanger under reduced gravity conditions  

E-Print Network [OSTI]

This work examines the effects of gravitational acceleration on the flow boiling process. A test facility focusing on an annular heat exchanger was designed, built out of borosilicate glass, and flown on NASA's KC-135 reduced gravity airplane...

Westheimer, David Thomas

2000-01-01T23:59:59.000Z

116

Experimental and Numerical Investigation of Pool Boiling Heat Transfer on Engineered Nano-Finned Surfaces  

E-Print Network [OSTI]

Pool boiling experiments for nanocoatings (or nanostructured surfaces) show that despite the lower thermal conductivity values than carbon, silicon yielded higher values of CHF (critical heat flux). Subsequently numerical studies showed...

Yang, Hongjoo

2014-08-10T23:59:59.000Z

117

A study of system-induced instabilities in forced-convection flows with subcooled boiling  

E-Print Network [OSTI]

A combined analytical and experimental program was carried out to investigate the problem of hydrodynamic stability of forcedconvection flows with boiling. The study was restricted to the flow of water in small channels ...

Maulbetsch, John S.

1965-01-01T23:59:59.000Z

118

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

119

Thermal non-equilibrium in dispersed flow film boiling in a vertical tube  

E-Print Network [OSTI]

The departure from thermal equilibrium between a dispersed liquid phase and its vapor at high quality during film boiling is investigated, The departure from equilibruim is manifested by the high resistance to heat transfer ...

Forslund, Robert Paul

1966-01-01T23:59:59.000Z

120

Experimental Two-Phase Flow Characterization of Subcooled Boiling in a Rectangular Channel  

E-Print Network [OSTI]

On the efforts to provide a reliable source of experimental information on turbulent subcooled boiling ow, time resolved Particle Tracking Velocimetry (PTV) experiments were carried out using HFE-301 refrigerant ow through a vertical rectangular...

Estrada Perez, Carlos E.

2010-01-16T23:59:59.000Z

Note: This page contains sample records for the topic "approximate boiling range" 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

Approximations to the Distributed Activation Energy Model  

E-Print Network [OSTI]

), used for the pyrolysis of a range of materials (including coal, biomass, residual oils and kerogen applies to the pyrolysis of other materials, including biomass, residual oils, resin chars [1Approximations to the Distributed Activation Energy Model for Pyrolysis C.P. Please, 1 M.J. Mc

McGuinness, Mark

122

Protective coatings for radiation control in boiling water nuclear power reactors  

SciTech Connect (OSTI)

Stainless-steel surfaces (316 nuclear grade) develop /sup 60/Co-embedded oxide scales when exposed to a boiling water reactor (BWR) environment. Thin films such as Pd, Ni, Au, and Cr were found to drastically reduce the radioactive buildup. The films were prepared by vacuum evaporation and electroless deposition. The electroless coating consisted of a thin cathodically treated layer, followed by a nickel strike (--1 ..mu..m) and an electroless layer (--600 A). The present paper describes the results obtained from a transmission electron microscope replica study of the radioactive growths that formed on uncoated and thin-film-coated stainless-steel rods. The coated rods, when exposed to a simulated BWR environment, exhibited corrosion film growths ranging from large faceted grains (uncoated) and isolated islands of similar crystallites (Au coated) to extremely small nucleated growths (Pd, Ni coated). Also, it was found that chromium oxide films, which generally form a protective oxide on stainless steel, do not completely stop either the corrosion film growth or the associated radioactive buildup. The morphologies of the corrosion film growth were correlated with the relative /sup 60/Co activity, and the substrate topography. The best coating to date was found to be a Pd thin film, 1000 A thick, which reduced the radioactive buildup by a factor of --13.

Rao, T.V.; Vook, R.W.; Meyer, W.; Wittwer, C.

1987-07-01T23:59:59.000Z

123

Boiling-Water Reactor internals aging degradation study. Phase 1  

SciTech Connect (OSTI)

This report documents the results of an aging assessment study for boiling water reactor (BWR) internals. Major stressors for BWR internals are related to unsteady hydrodynamic forces generated by the primary coolant flow in the reactor vessel. Welding and cold-working, dissolved oxygen and impurities in the coolant, applied loads and exposures to fast neutron fluxes are other important stressors. Based on results of a component failure information survey, stress corrosion cracking (SCC) and fatigue are identified as the two major aging-related degradation mechanisms for BWR internals. Significant reported failures include SCC in jet-pump holddown beams, in-core neutron flux monitor dry tubes and core spray spargers. Fatigue failures were detected in feedwater spargers. The implementation of a plant Hydrogen Water Chemistry (HWC) program is considered as a promising method for controlling SCC problems in BWR. More operating data are needed to evaluate its effectiveness for internal components. Long-term fast neutron irradiation effects and high-cycle fatigue in a corrosive environment are uncertainty factors in the aging assessment process. BWR internals are examined by visual inspections and the method is access limited. The presence of a large water gap and an absence of ex-core neutron flux monitors may handicap the use of advanced inspection methods, such as neutron noise vibration measurements, for BWR.

Luk, K.H. [Oak Ridge National Lab., TN (United States)

1993-09-01T23:59:59.000Z

124

Camera Inspection Arm for Boiling Water Reactors - 13330  

SciTech Connect (OSTI)

Boiling Water Reactor (BWR) outage maintenance tasks can be time-consuming and hazardous. Reactor facilities are continuously looking for quicker, safer, and more effective methods of performing routine inspection during these outages. In 2011, S.A. Technology (SAT) was approached by Energy Northwest to provide a remote system capable of increasing efficiencies related to Reactor Pressure Vessel (RPV) internal inspection activities. The specific intent of the system discussed was to inspect recirculation jet pumps in a manner that did not require manual tooling, and could be performed independently of other ongoing inspection activities. In 2012, SAT developed a compact, remote, camera inspection arm to create a safer, more efficient outage environment. This arm incorporates a compact and lightweight design along with the innovative use of bi-stable composite tubes to provide a six-degree of freedom inspection tool capable of reducing dose uptake, reducing crew size, and reducing the overall critical path for jet pump inspections. The prototype camera inspection arm unit is scheduled for final testing in early 2013 in preparation for the Columbia Generating Station refueling outage in the spring of 2013. (authors)

Martin, Scott; Rood, Marc [S.A. Technology, 3985 S. Lincoln Ave, Loveland, CO 80537 (United States)] [S.A. Technology, 3985 S. Lincoln Ave, Loveland, CO 80537 (United States)

2013-07-01T23:59:59.000Z

125

Aging study of boiling water reactor high pressure injection systems  

SciTech Connect (OSTI)

The purpose of high pressure injection systems is to maintain an adequate coolant level in reactor pressure vessels, so that the fuel cladding temperature does not exceed 1,200{degrees}C (2,200{degrees}F), and to permit plant shutdown during a variety of design basis loss-of-coolant accidents. This report presents the results of a study on aging performed for high pressure injection systems of boiling water reactor plants in the United States. The purpose of the study was to identify and evaluate the effects of aging and the effectiveness of testing and maintenance in detecting and mitigating aging degradation. Guidelines from the United States Nuclear Regulatory Commission`s Nuclear Plant Aging Research Program were used in performing the aging study. Review and analysis of the failures reported in databases such as Nuclear Power Experience, Licensee Event Reports, and the Nuclear Plant Reliability Data System, along with plant-specific maintenance records databases, are included in this report to provide the information required to identify aging stressors, failure modes, and failure causes. Several probabilistic risk assessments were reviewed to identify risk-significant components in high pressure injection systems. Testing, maintenance, specific safety issues, and codes and standards are also discussed.

Conley, D.A.; Edson, J.L.; Fineman, C.F. [Lockheed Idaho Technologies Co., Idaho Falls, ID (United States)

1995-03-01T23:59:59.000Z

126

Multi-cycle boiling water reactor fuel cycle optimization  

SciTech Connect (OSTI)

In this work a new computer code, BWROPT (Boiling Water Reactor Optimization), is presented. BWROPT uses the Parallel Simulated Annealing (PSA) algorithm to solve the out-of-core optimization problem coupled with an in-core optimization that determines the optimum fuel loading pattern. However it uses a Haling power profile for the depletion instead of optimizing the operating strategy. The result of this optimization is the optimum new fuel inventory and the core loading pattern for the first cycle considered in the optimization. Several changes were made to the optimization algorithm with respect to other nuclear fuel cycle optimization codes that use PSA. Instead of using constant sampling probabilities for the solution perturbation types throughout the optimization as is usually done in PSA optimizations the sampling probabilities are varied to get a better solution and/or decrease runtime. The new fuel types available for use can be sorted into an array based on any number of parameters so that each parameter can be incremented or decremented, which allows for more precise fuel type selection compared to random sampling. Also, the results are sorted by the new fuel inventory of the first cycle for ease of comparing alternative solutions. (authors)

Ottinger, K.; Maldonado, G.I. [University of Tennessee, 311 Pasqua Engineering Building, Knoxville, TN 37996-2300 (United States)

2013-07-01T23:59:59.000Z

127

An improved proximity force approximation for electrostatics  

SciTech Connect (OSTI)

A quite straightforward approximation for the electrostatic interaction between two perfectly conducting surfaces suggests itself when the distance between them is much smaller than the characteristic lengths associated with their shapes. Indeed, in the so called 'proximity force approximation' the electrostatic force is evaluated by first dividing each surface into a set of small flat patches, and then adding up the forces due two opposite pairs, the contributions of which are approximated as due to pairs of parallel planes. This approximation has been widely and successfully applied in different contexts, ranging from nuclear physics to Casimir effect calculations. We present here an improvement on this approximation, based on a derivative expansion for the electrostatic energy contained between the surfaces. The results obtained could be useful for discussing the geometric dependence of the electrostatic force, and also as a convenient benchmark for numerical analyses of the tip-sample electrostatic interaction in atomic force microscopes. - Highlights: Black-Right-Pointing-Pointer The proximity force approximation (PFA) has been widely used in different areas. Black-Right-Pointing-Pointer The PFA can be improved using a derivative expansion in the shape of the surfaces. Black-Right-Pointing-Pointer We use the improved PFA to compute electrostatic forces between conductors. Black-Right-Pointing-Pointer The results can be used as an analytic benchmark for numerical calculations in AFM. Black-Right-Pointing-Pointer Insight is provided for people who use the PFA to compute nuclear and Casimir forces.

Fosco, Cesar D. [Centro Atomico Bariloche, Comision Nacional de Energia Atomica, R8402AGP Bariloche (Argentina) [Centro Atomico Bariloche, Comision Nacional de Energia Atomica, R8402AGP Bariloche (Argentina); Instituto Balseiro, Universidad Nacional de Cuyo, R8402AGP Bariloche (Argentina); Lombardo, Fernando C. [Departamento de Fisica Juan Jose Giambiagi, FCEyN UBA, Facultad de Ciencias Exactas y Naturales, Ciudad Universitaria, Pabellon I, 1428 Buenos Aires (Argentina) [Departamento de Fisica Juan Jose Giambiagi, FCEyN UBA, Facultad de Ciencias Exactas y Naturales, Ciudad Universitaria, Pabellon I, 1428 Buenos Aires (Argentina); IFIBA (Argentina)] [Argentina; Mazzitelli, Francisco D., E-mail: fdmazzi@cab.cnea.gov.ar [Centro Atomico Bariloche, Comision Nacional de Energia Atomica, R8402AGP Bariloche (Argentina); Departamento de Fisica Juan Jose Giambiagi, FCEyN UBA, Facultad de Ciencias Exactas y Naturales, Ciudad Universitaria, Pabellon I, 1428 Buenos Aires (Argentina)

2012-08-15T23:59:59.000Z

128

Uniform asymptotic approximations of integrals   

E-Print Network [OSTI]

In this thesis uniform asymptotic approximations of integrals are discussed. In order to derive these approximations, two well-known methods are used i.e., the saddle point method and the Bleistein method. To start with ...

Khwaja, Sarah Farid

2014-07-01T23:59:59.000Z

129

Boiling behavior of sodium-potassium alloy in a bench-scale solar receiver  

SciTech Connect (OSTI)

During 1989-90, a 75-kW{sub t} sodium reflux pool-boiler solar receiver was successfully demonstrated at Sandia National Laboratories. Significant features of this receiver include (1) boiling sodium as the heat transfer medium and (2) electric-discharge-machined (EDM) cavities as artificial nucleation sites to stabilize boiling. Since this first demonstration, design of a second-generation pool-boiler receiver that will bring the concept closer to commercialization has begun. For long life, the new receiver uses Haynes Alloy 230. For increased safety factors against film boiling and flooding, it has a refined shape and somewhat larger dimensions. To eliminate the need for trace heating, the receiver will boil the sodium-potassium alloy NaK-78 instead of sodium. To reduce manufacturing costs, it will use one of a number of alternatives to EDM cavities for stabilization of boiling. To control incipient-boiling superheats, especially during hot restarts, it will contain a small amount of inert gas. Before the new receiver design could be finalized, bench-scale tests of some of the proposed changes were necessary. A series of bench-scale pool boilers were built from Haynes Alloy 230 and filled with NaK-78. Various boiling-stabilizer candidates were incorporated into them, including laser-drilled cavities and a number of different sintered-powder-metal coatings. These bench-scale pool boilers have been operated at temperatures up to 750{degree}C, heated by quartz lamps with incident radiant fluxes up to 95 W/cm{sup 2}. The effects of various orientations and added gases have been studied. results of these studies are presented. 15 refs.

Moreno, J.B.; Andraka, C.E.; Moss, T.A.

1992-01-01T23:59:59.000Z

130

Technology, safety and costs of decommissioning a reference boiling water reactor power station. Volume 2. Appendices. Technical report, September 1977-October 1979  

SciTech Connect (OSTI)

Technology, safety and cost information is given for the conceptual decommissioning of a large (1100MWe) boiling water reactor (BWR) power station. Three approaches to decommissioning, immediate dismantlement, safe storage with deferred dismantlement and entombment, were studied to obtain comparisons between costs, occupational radiation doses, potential dose to the public and other safety impacts. It also shows the sensitivity of decommissioning safety and costs to the power rating of a BWR in the range of 200 to 1100 MWE. This volume contains the appendices.

Oak, H.D.; Holter, G.M.; Kennedy, W.E. Jr.; Konzek, G.J.

1980-06-01T23:59:59.000Z

131

Film boiling on spheres in single- and two-phase flows.  

SciTech Connect (OSTI)

Film boiling on spheres in single- and two-phase flows was studied experimentally and theoretically with an emphasis on establishing the film boiling heat transfer closure law, which is useful in the analysis of nuclear reactor core melt accidents. Systematic experimentation of film boiling on spheres in single-phase water flows was carried out to investigate the effects of liquid subcooling (from 0 to 40 C), liquid velocity (from 0 to 2 m/s), sphere superheat (from 200 to 900 C), sphere diameter (from 6 to 19 mm), and sphere material (stainless steel and brass) on film boiling heat transfer. Based on the experimental data a general film boiling heat transfer correlation is developed. Utilizing a two-phase laminar boundary-layer model for the unseparated front film region and a turbulent eddy model for the separated rear region, a theoretical model was developed to predict the film boiling heat transfer in all single-phase regimes. The film boiling from a sphere in two-phase flows was investigated both in upward two-phase flows (with void fraction from 0.2 to 0.65, water velocity from 0.6 to 3.2 m/s, and steam velocity from 3.0 to 9.0 m/s) and in downward two-phase flows (with void fraction from 0.7 to 0.95, water velocity from 1.9 to 6.5 m/s, and steam velocity from 1.1 to 9.0 m/s). The saturated single-phase heat transfer correlation was found to be applicable to the two-phase film boiling data by making use of the actual water velocity (water phase velocity), and an adjustment factor of (1 - {alpha}){sup 1/4} (with a being the void fraction) for downward flow case only. Slight adjustments of the Reynolds number exponents in the correlation provided an even better interpretation of the two-phase data. Preliminary experiments were also conducted to address the influences of multi-sphere structure on the film boiling heat transfer in single- and two-phase flows.

Liu, C.; Theofanous, T. G.

2000-08-29T23:59:59.000Z

132

Two-dimensional computational modeling of sodium boiling in simulated LMFBR fuel-pin bundles  

SciTech Connect (OSTI)

Extensive sodium boiling tests have been carried out in two simulated LMFBR fuel pin bundles in the Thermal-Hydraulic Out-of-Reactor Safety (THORS) Facility at Oak Ridge National Laboratory. Experimental results from a 19-pin bundle (THORS Bundle 6A) have been previously reported, and experimental results from a 61-pin bundle (THORS Bundle 9) will be reported soon. The results discussed here are from the 19-pin bundle. Preliminary analysis has shown that the computational methods used and conclusions reached are equally valid for the 61-pin bundle, as well as the 19-pin in-reactor Sodium Loop Safety Facility (SLSF) W-1 experiment. The main result of THORS sodium boiling experimentation is that boiling behavior is determined by two-dimensional effects, i.e., the rates of mass, momentum and energy transfer in the direction perpendicular to the axes of the fuel pins.

Dearing, J.F.

1981-01-01T23:59:59.000Z

133

BOILING CRISIS:THEORY,SIMULATION,AND EXPERIMENTSBOILING CRISIS: THEORY, SIMULATION, AND EXPERIMENTS Boiling is a very efficient way to transfer heat from a heater to the liquid heat carrier. We discuss the  

E-Print Network [OSTI]

that separates the liquid from the heater. Film boiling can be also observed in the kitchen by sprinkling water onto a hot frying pan. In spite of the large temperature of the heater (the pan) the water drops Boiling is a very efficient way to transfer heat from a heater to the liquid heat carrier. We discuss

Nikolayev, Vadim S.

134

Approximate Dynamic Programming for High Dimensional Resource Allocation Problems  

E-Print Network [OSTI]

the dimensionality of these variables is in the ten thousand to one million range. We describe an approximation in Section II by presenting a simple but general model for the management of discrete resources. Section III describes an algorithmic strategy using the principles of approximate dynamic programming. Section IV

Powell, Warren B.

135

Analysis and Measurement of Bubble Dynamics and Associated Flow Field in Subcooled Nucleate Boiling Flows  

SciTech Connect (OSTI)

In recent years, subooled nucleate boiling (SNB) has attrcted expanding research interest owing to the emergence of axial offset anomaly (AOA) or crud-induced power shigt (CIPS) in many operating US PWRs, which is an unexpected deviation in the core axial power distribution from the predicted power curves. Research indicates that the formation of the crud, which directly leads to AOA phenomena, results from the presence of the subcooled nucleate boiling, and is especially realted to bubble motion occurring in the core region.

Barclay G. Jones

2008-10-01T23:59:59.000Z

136

The use of the probability distribution function to analyze surface temperature fluctuations in pool boiling  

E-Print Network [OSTI]

' '. t 1 . 1 1 q 'd. C t' ~bl', 1. 11 d tl b '1 q, - b '1' q ' b 1 in which fluid flows or boiling outside the channel over The citations used follow the style and format of Transaction of the ASMEi - Journal of Heat Transfer. which fluid flows.... In convective boiling, the heating sur- face is the channel wall and the direction of heat transfer through the heating surface may be either from inside the channel to the outside or vice versa. For instance, feed- water flowing inside economizer tubes...

Tu, Chau Qui

1976-01-01T23:59:59.000Z

137

Investigation of boiling heat transfer at a surface with a system of cylindrical cavities under conditions of free motion  

SciTech Connect (OSTI)

The authors propose a mathematical model for the intensification of boiling heat transfer and the subsequent increase in thermal efficiency of the cylindrical heat transfer surfaces in an evaporative cooling system. The boiling curves for water, ethanol, and freon 113 are calculated for a surface with artificial nucleation sites. The model incorporates such coolant properties as surface tension, specific heat, and vaporization heat.

Danilova, G.N.; Reznikov, V.I.

1988-01-01T23:59:59.000Z

138

Nanoscale modification of key surface parameters to augment pool boiling heat transfer and critical heat flux in water and dielectric fluids  

E-Print Network [OSTI]

Surface effects on pool boiling heat transfer and the critical heat flux are well documented but poorly understood. This study investigates the pool boiling characteristics of various fluids, and demonstrates that surface ...

Forrest, Eric Christopher

2009-01-01T23:59:59.000Z

139

Validation and Calibration of Nuclear Thermal Hydraulics Multiscale Multiphysics Models - Subcooled Flow Boiling Study  

SciTech Connect (OSTI)

In addition to validation data plan, development of advanced techniques for calibration and validation of complex multiscale, multiphysics nuclear reactor simulation codes are a main objective of the CASL VUQ plan. Advanced modeling of LWR systems normally involves a range of physico-chemical models describing multiple interacting phenomena, such as thermal hydraulics, reactor physics, coolant chemistry, etc., which occur over a wide range of spatial and temporal scales. To a large extent, the accuracy of (and uncertainty in) overall model predictions is determined by the correctness of various sub-models, which are not conservation-laws based, but empirically derived from measurement data. Such sub-models normally require extensive calibration before the models can be applied to analysis of real reactor problems. This work demonstrates a case study of calibration of a common model of subcooled flow boiling, which is an important multiscale, multiphysics phenomenon in LWR thermal hydraulics. The calibration process is based on a new strategy of model-data integration, in which, all sub-models are simultaneously analyzed and calibrated using multiple sets of data of different types. Specifically, both data on large-scale distributions of void fraction and fluid temperature and data on small-scale physics of wall evaporation were simultaneously used in this work’s calibration. In a departure from traditional (or common-sense) practice of tuning/calibrating complex models, a modern calibration technique based on statistical modeling and Bayesian inference was employed, which allowed simultaneous calibration of multiple sub-models (and related parameters) using different datasets. Quality of data (relevancy, scalability, and uncertainty) could be taken into consideration in the calibration process. This work presents a step forward in the development and realization of the “CIPS Validation Data Plan” at the Consortium for Advanced Simulation of LWRs to enable quantitative assessment of the CASL modeling of Crud-Induced Power Shift (CIPS) phenomenon, in particular, and the CASL advanced predictive capabilities, in general. This report is prepared for the Department of Energy’s Consortium for Advanced Simulation of LWRs program’s VUQ Focus Area.

Anh Bui; Nam Dinh; Brian Williams

2013-09-01T23:59:59.000Z

140

2007-No54-BoilingPoint Health and Greenhouse Gas Impacts of Biomass and Fossil Fuel  

E-Print Network [OSTI]

2007-No54-BoilingPoint Theme Health and Greenhouse Gas Impacts of Biomass and Fossil Fuel Energy of fossil-fuel energy systems. These scenarios are analysed for various environmental and health impacts from fossil fuels and other energy sources reported by IEA []. In all of these countries except Kenya

Kammen, Daniel M.

Note: This page contains sample records for the topic "approximate boiling range" 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.


141

Boiling heat transfer in a hydrofoil-based micro pin fin heat sink  

E-Print Network [OSTI]

Boiling heat transfer in a hydrofoil-based micro pin fin heat sink Ali KosÃ?ar, Yoav Peles-based micro pin fin heat sink was investigated. Average two-phase heat transfer coefficients were obtained intermittent and spray-annular flows. Heat transfer coefficient trends and flow morphologies were used to infer

Peles, Yoav

142

INVESTIGATING THE EFFECT OF HEATING METHOD ON POOL BOILING HEAT TRANSFER  

E-Print Network [OSTI]

INVESTIGATING THE EFFECT OF HEATING METHOD ON POOL BOILING HEAT TRANSFER Satish G. Kandlikar surfaces in laboratories to obtain the heat transfer coefficient data. In many process applications however, a fluid stream is employed as the heating medium. The heat transfer data generated with the electrically

Kandlikar, Satish

143

"Hot Water" in Lassen Volcanic National Park--Fumaroles, Steaming Ground, and Boiling Mudpots  

E-Print Network [OSTI]

"Hot Water" in Lassen Volcanic National Park-- Fumaroles, Steaming Ground, and Boiling Mudpots U, ydrothermal (hot water) and steaming ground. These features are re- lated to active volcanism, the largest fumarole (steam and volcanic-gas vent) in the park. The temperature of the high-velocity steam

Torgersen, Christian

144

Hydrodynamic cavitation and boiling in refrigerant (R-123) flow inside microchannels  

E-Print Network [OSTI]

Hydrodynamic cavitation and boiling in refrigerant (R-123) flow inside microchannels Brandon cavitation has on heat transfer. The fluid medium is refrigerant R-123 flowing through 227 lm hydraulic diameter microchannels. The cavitation is instigated by the inlet orifice. Adiabatic tests were con- ducted

Peles, Yoav

145

Numerical simulation of boiling during the quenching process N. Kosseifi1  

E-Print Network [OSTI]

by computing the heat flux that arises from the different modes of boiling. They coupled the phase change to heat dissipation of the metal thanks to an interface coupling code. The heat transfer coefficient using a level set method. Surface tension is evaluated using the continuum surface force. The proposed

Paris-Sud XI, Université de

146

Simulation of subcooled boiling at low pressure conditions with RELAP5-3D computer program  

E-Print Network [OSTI]

. Experimental data from the subcooled boiling experiment at low pressure conditions of Bartel, and Zeitoun and Shoukri were simulated. The RELAP5/MOD3.2 was executed to determine the axial void faction distribution. The predictions of void fraction distributions...

Reza, S.M. Mohsin

2002-01-01T23:59:59.000Z

147

A mathematical method for boiling water reactor control rod programming  

SciTech Connect (OSTI)

A new mathematical programming method has been developed and utilized in OPROD, an existing computer code for automatic generation of control rod programs as an alternative inner-loop routine for the method of approximate programming. The new routine is constructed of a dual feasible direction algorithm, and consists essentially of two stages of iterative optimization procedures Optimization Procedures I and II. Both follow almost the same algorithm; Optimization Procedure I searches for feasible solutions and Optimization Procedure II optimizes the objective function. Optimization theory and computer simulations have demonstrated that the new routine could find optimum solutions, even if deteriorated initial control rod patterns were given.

Tokumasu, S.; Hiranuma, H.; Ozawa, M.; Yokomi, M.

1985-12-01T23:59:59.000Z

148

Approximation Algorithms for Covering Problems  

E-Print Network [OSTI]

?-approximation for general CIP with {0, 1} variables [24].details of an extension to CIP with general upper bounds onCovering Integer Programs ( CIP ). Given a non-negative cost

Koufogiannakis, Christos

2009-01-01T23:59:59.000Z

149

Mechanism design with approximate types  

E-Print Network [OSTI]

In mechanism design, we replace the strong assumption that each player knows his own payoff type exactly with the more realistic assumption that he knows it only approximately: each player i only knows that his true type ...

Zhu, Zeyuan Allen

2012-01-01T23:59:59.000Z

150

Transient approximations in queueing networks  

E-Print Network [OSTI]

TRANSIENT APPROXIMATIONS IN QUEUEING NETWORKS A Thesis by JOHN MICHAEL ANDREWARTHA Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 1989... Major Subject: Electrical Engineering TRANSIENT APPROXIMATIONS IN QUEUEING NETWORKS A Thesis JOHN MICHAEL ANDREWARTHA Approved as to style and content by: P. E. Cantrell (Chair of Committee) m P7~ W. K. Tsai (Member) J. D. Gibson (Member) R...

Andrewartha, John Michael

1989-01-01T23:59:59.000Z

151

Ancilla Approximable Quantum State Transformations  

E-Print Network [OSTI]

We consider the transformations of quantum states obtainable by a process of the following sort. Combine the given input state with a specially prepared initial state of an auxiliary system. Apply a unitary transformation to the combined system. Measure the state of the auxiliary subsystem. If (and only if) it is in a specified final state, consider the process successful, and take the resulting state of the original (principal) system as the result of the process. We review known information about exact realization of transformations by such a process. Then we present results about approximate realization of finite partial transformations. We consider primarily the issue of approximation to within a specified positive epsilon, but we also address the question of arbitrarily close approximation.

Andreas Blass; Yuri Gurevich

2014-03-30T23:59:59.000Z

152

Quasiclassical Born-Oppenheimer approximations  

E-Print Network [OSTI]

We discuss several problems in quasiclassical physics for which approximate solutions were recently obtained by a new method, and which can also be solved by novel versions of the Born-Oppenheimer approximation. These cases include the so-called bouncing ball modes, low angular momentum states in perturbed circular billiards, resonant states in perturbed rectangular billiards, and whispering gallery modes. Some rare, special eigenstates, concentrated close to the edge or along a diagonal of a nearly rectangular billiard are found. This kind of state has apparently previously escaped notice.

Oleg Zaitsev; R. Narevich; R. E. Prange

2000-09-29T23:59:59.000Z

153

Development of a general purpose subgrid wall boiling model from improved physical understanding for use in computational fluid dynamics  

E-Print Network [OSTI]

Advanced modeling capabilities were developed for application to subcooled flow boiling through this work. The target was to introduce, and demonstrate, all necessary mechanisms required to accurately predict the temperature ...

Gilman, Lindsey Anne

2014-01-01T23:59:59.000Z

154

Subcooled flow boiling heat transfer and critical heat flux in water-based nanofluids at low pressure  

E-Print Network [OSTI]

A nanofluid is a colloidal suspension of nano-scale particles in water, or other base fluids. Previous pool boiling studies have shown that nanofluids can improve the critical heat flux (CHF) by as much as 200%. In this ...

Kim, Sung Joong, Ph. D. Massachusetts Institute of Technology

2009-01-01T23:59:59.000Z

155

A four-equation two-phase flow model for sodium boiling simulation of LMFBR fuel assemblies  

E-Print Network [OSTI]

A three-dimensional numerical model for the simulation of sodium boiling transients has been developed. The model uses mixture mass and energy equations, while employing a separate momentum equation for each phase. Thermal ...

Schor, Andrei L.

1982-01-01T23:59:59.000Z

156

Effect of combined nanoparticle and polymeric dispersions on critical heat flux, nucleate boiling heat transfer coefficient, and coating adhesion  

E-Print Network [OSTI]

An experimental study was performed to determine thermal performance and adhesion effects of a combined nanoparticle and polymeric dispersion coating. The critical heat flux (CHF) values and nucleate boiling heat transfer ...

Edwards, Bronwyn K

2009-01-01T23:59:59.000Z

157

Experimental pool boiling investigation of FC-72 on silicon with artificial cavities, integrated temperature micro-sensors and heater   

E-Print Network [OSTI]

Today nucleate boiling is widely used in numerous industrial applications such as cooling processes because of the high achieved heat transfer rates for low temperature differences. It remains a possible cooling solution ...

Hutter, Christian

2010-01-01T23:59:59.000Z

158

Film boiling on the inside of vertical tubes with upward flow of the fluid at low qualities  

E-Print Network [OSTI]

Flow regimes, local heat transfer coefficients, and temperature distributions along the wall have been studied for film boiling inside a vertical tube with upward flow of a saturated liquid. The area of interest has been ...

Dougall, R. S.

1963-01-01T23:59:59.000Z

159

Experimental investigation of subcooled flow boiling using synchronized high speed video, infrared thermography, and particle image velocimetry  

E-Print Network [OSTI]

Subcooled flow boiling of water was experimentally investigated using high-speed video (HSV), infrared (IR) thermography, and particle image velocimetry (PIV) to generate a unique database of synchronized data. HSV allowed ...

Phillips, Bren Andrew

2014-01-01T23:59:59.000Z

160

Study of bubble growth in water pool boiling through synchronized, infrared thermometry and high-speed video  

E-Print Network [OSTI]

High-speed video and infrared thermometry were used to obtain time- and space-resolved information on bubble nucleation and heat transfer in pool boiling of water. The bubble departure diameter and frequency, growth and ...

Gerardi, Craig

Note: This page contains sample records for the topic "approximate boiling range" 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

Development of models for the two-dimensional, two-fluid code for sodium boiling NATOF-2D  

E-Print Network [OSTI]

Several features were incorporated into NATOF-2D, a twodimensional, two fluid code developed at M.I.T. for the purpose of analysis of sodium boiling transients under LMFBR conditions. They include improved interfacial mass, ...

Zielinski, R. G.

1981-01-01T23:59:59.000Z

162

Analytic approximate radiation effects due to Bremsstrahlung  

SciTech Connect (OSTI)

The purpose of this note is to provide analytic approximate expressions that can provide quick estimates of the various effects of the Bremsstrahlung radiation produced relatively low energy electrons, such as the dumping of the beam into the beam stop at the ERL or field emission in superconducting cavities. The purpose of this work is not to replace a dependable calculation or, better yet, a measurement under real conditions, but to provide a quick but approximate estimate for guidance purposes only. These effects include dose to personnel, ozone generation in the air volume exposed to the radiation, hydrogen generation in the beam dump water cooling system and radiation damage to near-by magnets. These expressions can be used for other purposes, but one should note that the electron beam energy range is limited. In these calculations the good range is from about 0.5 MeV to 10 MeV. To help in the application of this note, calculations are presented as a worked out example for the beam dump of the R&D Energy Recovery Linac.

Ben-Zvi I.

2012-02-01T23:59:59.000Z

163

Tracking Dynamic Boundary Fronts using Range Sensors  

E-Print Network [OSTI]

are being deployed for real-time monitoring applica- tions, such as detecting leakage of hazardous material location whereas in the latter approach a sensor finds approximate distance to a remote location where degrees and gather reflec- tivity and wind velocity information. Lidars (LIght Detection and Ranging

Ramamritham, Krithi

164

Two-dimensional modeling of sodium boiling transients in simulated LMFBR fuel bundles  

SciTech Connect (OSTI)

A two-dimensional code for analysis of sodium boiling in LMFBR fuel assemblies has been developed at ORNL. This code, THORAX, has been used to analyze tests in 19- and 61-pin electrically-heated, simulated LMFBR fuel assemblies in the THORS facility. THORAX has simulated well the transient growth of the two-dimensional boiling region and the resulting static flow instability leading to dryout. Extrapolation of results to a full size fuel pin bundle shows that two-dimensional effects are reduced but still significant. The code will be extended to include a loop model in support of forthcoming tests in the THORS-SHRS Assembly 1 loop, which will include two parallel 19-pin simulated driver bundles.

Rose, S.D.; Dearing, J.F; Carbajo, J.J.; Levin, A.E.; Montgomery, B.H.; Wantland, J.L.

1982-01-01T23:59:59.000Z

165

Two dimensional, two fluid model for sodium boiling in LMFBR fuel assemblies  

SciTech Connect (OSTI)

A two dimensional numerical model for the simulation of sodium boiling transient was developed using the two fluid set of conservation equations. A semiimplicit numerical differencing scheme capable of handling the problems associated with the ill-posedness implied by the complex characteristic roots of the two fluid problems was used, which took advantage of the dumping effect of the exchange terms. Of particular interest in the development of the model was the identification of the numerical problems caused by the strong disparity between the axial and radial dimensions of fuel assemblies. A solution to this problem was found which uses the particular geometry of fuel assemblies to accelerate the convergence of the iterative technique used in the model. Three sodium boiling experiments were simulated with the model, with good agreement between the experimental results and the model predictions.

Granziera, M.R.; Kazimi, M.S.

1980-05-01T23:59:59.000Z

166

Design, construction and testing of a boiling and convective condensation experiment for use in a microgravity environment  

E-Print Network [OSTI]

travel in the direction of flow. Slug flow occurs when the waves get large enough to reach across the tube. A frothy slug which is propagated along the channel at a high velocity can also form. Annular flow is characterized by a liquid film around... 6mm ID, 8mm OD glass tubes. Observation included direct visual observation and high speed photography of both boiling and condensing flow. Measurements taken included the pressure, and temperature drops associated with both boiling and condensing...

Kachnik, Leo Joseph

1987-01-01T23:59:59.000Z

167

Convective currents in nucleate pool boiling and their effects on the heat flux from varying diameter flat plate heating elements  

E-Print Network [OSTI]

investigation was conducred to amine the effects of convection currents in nucleate oool boil ing and to determine the changes in critical heat flux caused by varying the diameter of horizontal flat olate heating surfaces. Freon 113 (Trichlorotrifluoroethane... by high energy costs and thc need to economize in industrial heat transfer applications . I'nucleate boiling is a very efficient neans of heat transfer because of the large sur ace areas involved in vaporization of the bulk fluid. as bubbles form...

Morford, Peter Stephen

1980-01-01T23:59:59.000Z

168

Multi-scale Control and Enhancement of Reactor Boiling Heat Flux by Reagents and Nanoparticles  

SciTech Connect (OSTI)

The phenomenological characterization of the use of non-invasive and passive techniques to enhance the boiling heat transfer in water has been carried out in this extended study. It provides fundamental enhanced heat transfer data for nucleate boiling and discusses the associated physics with the aim of addressing future and next-generation reactor thermal-hydraulic management. It essentially addresses the hypothesis that in phase-change processes during boiling, the primary mechanisms can be related to the liquid-vapor interfacial tension and surface wetting at the solidliquid interface. These interfacial characteristics can be significantly altered and decoupled by introducing small quantities of additives in water, such as surface-active polymers, surfactants, and nanoparticles. The changes are fundamentally caused at a molecular-scale by the relative bulk molecular dynamics and adsorption-desorption of the additive at the liquid-vapor interface, and its physisorption and electrokinetics at the liquid-solid interface. At the micro-scale, the transient transport mechanisms at the solid-liquid-vapor interface during nucleation and bubblegrowth can be attributed to thin-film spreading, surface-micro-cavity activation, and micro-layer evaporation. Furthermore at the macro-scale, the heat transport is in turn governed by the bubble growth and distribution, macro-layer heat transfer, bubble dynamics (bubble coalescence, collapse, break-up, and translation), and liquid rheology. Some of these behaviors and processes are measured and characterized in this study, the outcomes of which advance the concomitant fundamental physics, as well as provide insights for developing control strategies for the molecular-scale manipulation of interfacial tension and surface wetting in boiling by means of polymeric reagents, surfactants, and other soluble surface-active additives.

R.M. Manglik; A. Athavale; D.S. Kalaikadal; A. Deodhar; U. Verma

2011-09-02T23:59:59.000Z

169

Improved approximate formulas for flux from cylindrical and rectangular sources  

SciTech Connect (OSTI)

This report provides two new approximate formulas for the flux at detector points outside the radial and axial extensions of a homogeneous cylindrical source and improved approximate formulas for the flux at points opposite rectangular surface sources. These formulas extend the range of geometries for which analytic approximations may be used by shield design engineers to make rapid scoping studies and check more extensive calculations for reasonableness. These formulas can be used to support skeptical, independent evaluations and are also valuable teaching tools for introducing shield designers to complex shield analyses.

Wallace, O.J.; Bokharee, S.A.

1993-03-01T23:59:59.000Z

170

Approximate convex decomposition and its applications  

E-Print Network [OSTI]

in representations with an unmanageable number of components. In this work, we have developed an approximate technique, called Approximate Convex Decomposition (ACD), which decomposes a given polygon or polyhedron into "approximately convex" pieces that may provide...

Lien, Jyh-Ming

2009-05-15T23:59:59.000Z

171

RANGE DESIGN CRITERIA  

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

firing lanes. If possible, do not construct columns within the range. Design columns or beams to withstand local wind and seismic loads, and provide protective steel plate on the...

172

Approximating Metal-Insulator Transitions  

E-Print Network [OSTI]

We consider quantum wave propagation in one-dimensional quasiperiodic lattices. We propose an iterative construction of quasiperiodic potentials from sequences of potentials with increasing spatial period. At each finite iteration step the eigenstates reflect the properties of the limiting quasiperiodic potential properties up to a controlled maximum system size. We then observe approximate metal-insulator transitions (MIT) at the finite iteration steps. We also report evidence on mobility edges which are at variance to the celebrated Aubry-Andre model. The dynamics near the MIT shows a critical slowing down of the ballistic group velocity in the metallic phase similar to the divergence of the localization length in the insulating phase.

C. Danieli; K. Rayanov; B. Pavlov; G. Martin; S. Flach

2014-05-06T23:59:59.000Z

173

Non-ideal boson system in the Gaussian approximation  

SciTech Connect (OSTI)

We investigate ground-state and thermal properties of a system of non-relativistic bosons interacting through repulsive, two-body interactions in a self-consistent Gaussian mean-field approximation which consists in writing the variationally determined density operator as the most general Gaussian functional of the quantized field operators. Finite temperature results are obtained in a grand canonical framework. Contact is made with the results of Lee, Yang, and Huang in terms of particular truncations of the Gaussian approximation. The full Gaussian approximation supports a free phase or a thermodynamically unstable phase when contact forces and a standard renormalization scheme are used. When applied to a Hamiltonian with zero range forces interpreted as an effective theory with a high momentum cutoff, the full Gaussian approximation generates a quasi-particle spectrum having an energy gap, in conflict with perturbation theory results. {copyright} 1997 Academic Press, Inc.

Tommasini, P.R. [Institute for Theoretical Atomic and Molecular Physics, Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138 (United States)] [Institute for Theoretical Atomic and Molecular Physics, Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138 (United States); de Toledo Piza, A.F. [Instituto de Fisica, Universidade de Sao Paulo, C.P. 66318, 05389-970 Sao Paulo, SP, (Brasil)] [Instituto de Fisica, Universidade de Sao Paulo, C.P. 66318, 05389-970 Sao Paulo, SP, (Brasil)

1997-01-01T23:59:59.000Z

174

Analysis of the magnetic corrosion product deposits on a boiling water reactor cladding  

SciTech Connect (OSTI)

The buildup of corrosion product deposits (CRUD) on the fuel cladding of the boiling water reactor (BWR) before and after zinc injection has been investigated by applying local experimental analytical techniques. Under the BWR water chemistry conditions, Zn addition together with the presence of Ni and Mn induce the formation of (Zn,Ni,Mn)[Fe{sub 2}O{sub 4}] spinel solid solutions. X-ray absorption spectroscopy (XAS) revealed inversion ratios of cation distribution in spinels deposited from the solid solution. Based on this information, a two-site ferrite spinel solid solution model is proposed. Electron probe microanalysis (EPMA) and extended X-ray absorption fine structure (EXAFS) findings suggest the zinc-rich ferrite spinels formation on BWR fuel cladding mainly at lower pin. - Graphical Abstract: Analysis of spinels in corrosion product deposits on boiling water reactor fuel rod. Combining EPMA and XAFS results: schematic representation of the ferrite spinels in terms of the end members and their extent of inversion. Note that the ferrites are represented as a surface between the normal (upper plane, M[Fe{sub 2}]O{sub 4}) and the inverse (lower plane, Fe[MFe]O{sub 4}). Actual compositions red Black-Small-Square for the specimen at low elevation (810 mm), blue Black-Small-Square for the specimen at mid elevation (1800 mm). The results have an impact on the properties of the CRUD material. Highlights: Black-Right-Pointing-Pointer Buildup of corrosion product deposits on fuel claddings of a boiling water reactor (BWR) are investigated. Black-Right-Pointing-Pointer Under BWR water conditions, Zn addition with Ni and Mn induced formation of (Zn,Ni,Mn)[Fe{sub 2}O{sub 4}]. Black-Right-Pointing-Pointer X-Ray Adsorption Spectroscopy (XAS) revealed inversion of cations in spinel solid solutions. Black-Right-Pointing-Pointer Zinc-rich ferrite spinels are formed on BWR fuel cladding mainly at lower pin elevations.

Orlov, Andrey [Paul Scherrer Institut, Villigen (Switzerland); Degueldre, Claude, E-mail: claude.degueldre@psi.ch [Paul Scherrer Institut, Villigen (Switzerland); Kaufmann, Wilfried [Kernkraftwerk Leibstadt, Leibstadt (Switzerland)

2013-01-15T23:59:59.000Z

175

Evaluation of nonequilibrium effects in bundle dispersed-flow film boiling. [PWR; BWR  

SciTech Connect (OSTI)

The effects of thermodynamic nonequilibrium in dispersed flow film boiling heat transfer are examined. Steady-state and transient rod-bundle data are used to evaluate several empirical heat-transfer models commonly employed to predict post-CHF behavior. The models that account for thermodynamic nonequilibrium perform adequately, while those that ignore nonequilibrium effects incur errors in wall superheat as high as 190/sup 0/K. Nonequilibrium effects can also be treated by explicitly modeling the phenomena. The thermal-hydraulic code COBRA-TF employs this approach. Using bundle data, the models in the code are evaluated. Analysis suggests that the interfacial heat transfer is overpredicted.

Morris, D.G.; Mullins, C.B.; Yoder, G.L.

1983-01-01T23:59:59.000Z

176

Modeling Single-Phase and Boiling Liquid Jet Impingement Cooling in Power Electronics  

SciTech Connect (OSTI)

Jet impingement has been an attractive cooling option in a number of industries over the past few decades. Over the past 15 years, jet impingement has been explored as a cooling option in microelectronics. Recently, interest has been expressed by the automotive industry in exploring jet impingement for cooling power electronics components. This technical report explores, from a modeling perspective, both single-phase and boiling jet impingement cooling in power electronics, primarily from a heat transfer viewpoint. The discussion is from the viewpoint of the cooling of IGBTs (insulated-gate bipolar transistors), which are found in hybrid automobile inverters.

Narumanchi, S. V. J.; Hassani, V.; Bharathan, D.

2005-12-01T23:59:59.000Z

177

Enhancement of pool boiling heat transfer with electrohydrodynamics and its fundamental study  

E-Print Network [OSTI]

, enhancements of up to an order of magnitude was achieved. Cooper (1990) made visual observations and noted that when an electrode potential of about 5-8 kV was applied to R-114 at a few degrees of superheat, immediate activation of nucleation sites all over..., and 10kV. To conduct this study, an existing low pressure pool boiling apparatus was modified and another high pressure apparatus was designed and built. The fluids were tested on the smooth tube at operating temperatures of 4'C and 20'C, and 19 fins...

Raghupathi, Sri Laxmi Priya

1998-01-01T23:59:59.000Z

178

Light beam range finder  

DOE Patents [OSTI]

A "laser tape measure" for measuring distance which includes a transmitter such as a laser diode which transmits a sequence of electromagnetic pulses in response to a transmit timing signal. A receiver samples reflections from objects within the field of the sequence of visible electromagnetic pulses with controlled timing, in response to a receive timing signal. The receiver generates a sample signal in response to the samples which indicates distance to the object causing the reflections. The timing circuit supplies the transmit timing signal to the transmitter and supplies the receive timing signal to the receiver. The receive timing signal causes the receiver to sample the reflection such that the time between transmission of pulses in the sequence in sampling by the receiver sweeps over a range of delays. The transmit timing signal causes the transmitter to transmit the sequence of electromagnetic pulses at a pulse repetition rate, and the received timing signal sweeps over the range of delays in a sweep cycle such that reflections are sampled at the pulse repetition rate and with different delays in the range of delays, such that the sample signal represents received reflections in equivalent time. The receiver according to one aspect of the invention includes an avalanche photodiode and a sampling gate coupled to the photodiode which is responsive to the received timing signal. The transmitter includes a laser diode which supplies a sequence of visible electromagnetic pulses. A bright spot projected on to the target clearly indicates the point that is being measured, and the user can read the range to that point with precision of better than 0.1%.

McEwan, Thomas E. (Livermore, CA)

1998-01-01T23:59:59.000Z

179

Light beam range finder  

DOE Patents [OSTI]

A ``laser tape measure`` for measuring distance is disclosed which includes a transmitter such as a laser diode which transmits a sequence of electromagnetic pulses in response to a transmit timing signal. A receiver samples reflections from objects within the field of the sequence of visible electromagnetic pulses with controlled timing, in response to a receive timing signal. The receiver generates a sample signal in response to the samples which indicates distance to the object causing the reflections. The timing circuit supplies the transmit timing signal to the transmitter and supplies the receive timing signal to the receiver. The receive timing signal causes the receiver to sample the reflection such that the time between transmission of pulses in the sequence in sampling by the receiver sweeps over a range of delays. The transmit timing signal causes the transmitter to transmit the sequence of electromagnetic pulses at a pulse repetition rate, and the received timing signal sweeps over the range of delays in a sweep cycle such that reflections are sampled at the pulse repetition rate and with different delays in the range of delays, such that the sample signal represents received reflections in equivalent time. The receiver according to one aspect of the invention includes an avalanche photodiode and a sampling gate coupled to the photodiode which is responsive to the received timing signal. The transmitter includes a laser diode which supplies a sequence of visible electromagnetic pulses. A bright spot projected on to the target clearly indicates the point that is being measured, and the user can read the range to that point with precision of better than 0.1%. 7 figs.

McEwan, T.E.

1998-06-16T23:59:59.000Z

180

CORQUENCH: A model for gas sparging-enhanced, melt-water, film-boiling heat transfer  

SciTech Connect (OSTI)

In evaluation of severe-accident sequences for water-cooled nuclear reactors, molten core materials may be postulated to be released into the containment and accumulate on concrete. The heatup and decomposition of concrete is accompanied by the release of water vapor and carbon dioxide gases. Gases flowing through the melt upper surface can influence the rates of heat transfer to water overlying the melt. In particular, the gas flow through the interface can be envisioned to enhance the heat removal from the melt. A mechanistic model (CORQUENCH) has been developed to describe film-boiling heat transfer between a molten pool and an overlying coolant layer in the presence of sparging gas. The model favorably predicts the lead-Feron 11 data of Greene and Greene et al. for which the calculations indicate that area enhancement in the conduction heat transfer across the film is the predominant mechanism leading to augmentation in the heat flux as the gas velocity increases. Predictions for oxidic corium indicate a rapid increase in film-boiling heat flux as the gas velocity rises. The predominant mode of heat transfer for this case is radiation, and the increase in heat flux with gas velocity is primarily a result of interfacial area enhancement of the radiation component of the overall heat transfer coefficient. The CORQUENCH model has been incorporated into the MELTSPREAD-1 computer code{sup 6} for the analysis of transient spreading in containments.

Farmer, M.T.; Sienicki, J.J.; Spencer, B.W.

1990-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "approximate boiling range" 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

Magnetic thaw-down and boil-off due to magneto acceptors in 2DEG  

SciTech Connect (OSTI)

The Quantum Hall Effect (QHE) and Shubnikov-de Haas effect are investigated experimentally using n type modulation-doped GaAs/GaAlAs quantum wells (QWs) additionally doped in the well with beryllium acceptor atoms. It is presently shown that the localized magneto-acceptor (MA) states which possess discrete energies above the corresponding Landau levels (LLs) lead to two observable effects in magneto-transport: magnetic thaw-down and magnetic boil-off of 2D electrons. Both effects are related to the fact that electrons occupying the localized MA states cannot conduct. Thus in the thaw-down effect the electrons fall down from the MA states to the free Landau states. This leads to a shift of the Hall plateau towards higher magnetic fields as a consequence of an increase of the 2D electron density N{sub S}. In the boil-off effect the electrons are pushed from the free Landau states to the empty MA states under high enough Hall electric field. This process has an avalanche character leading to a dramatic increase of magneto-resistance, consequence of a decrease of N{sub S}.

Chaubet, C.; Raymond, A. [L2C UMR 5221, CNRS-Université Montpellier 2, Place E. Bataillon, 34090 Montpellier cedex 05 (France); Bisotto, I. [LNCMI, UPR 3228, CNRS-INSA-UJF-UPS, BP166, 38042 Grenoble, Cedex 9 (France); Harmand, J. C. [LPN, CNRS, route de Nozay, 91460 Marcoussis (France); Kubisa, M. [Institute of Physics, Wroclaw University of Technology, 50-370 Wroclaw (Poland); Zawadzki, W. [Institute of Physics, Polish Academy of Sciences, 02668 Warsaw (Poland)

2013-12-04T23:59:59.000Z

182

Performance of Charcoal Cookstoves for Haiti Part 1: Results from the Water Boiling Test  

SciTech Connect (OSTI)

In April 2010, a team of scientists and engineers from Lawrence Berkeley National Lab (LBNL) and UC Berkeley, with support from the Darfur Stoves Project (DSP), undertook a fact-finding mission to Haiti in order to assess needs and opportunities for cookstove intervention. Based on data collected from informal interviews with Haitians and NGOs, the team, Scott Sadlon, Robert Cheng, and Kayje Booker, identified and recommended stove testing and comparison as a high priority need that could be filled by LBNL. In response to that recommendation, five charcoal stoves were tested at the LBNL stove testing facility using a modified form of version 3 of the Shell Foundation Household Energy Project Water Boiling Test (WBT). The original protocol is available online. Stoves were tested for time to boil, thermal efficiency, specific fuel consumption, and emissions of CO, CO{sub 2}, and the ratio of CO/CO{sub 2}. In addition, Haitian user feedback and field observations over a subset of the stoves were combined with the experiences of the laboratory testing technicians to evaluate the usability of the stoves and their appropriateness for Haitian cooking. The laboratory results from emissions and efficiency testing and conclusions regarding usability of the stoves are presented in this report.

Booker, Kayje; Han, Tae Won; Granderson, Jessica; Jones, Jennifer; Lsk, Kathleen; Yang, Nina; Gadgil, Ashok

2011-06-01T23:59:59.000Z

183

Physical modeling and numerical simulation of subcooled boiling in one- and three-dimensional representation of bundle geometry  

SciTech Connect (OSTI)

Numerical simulation of subcooled boiling in one-dimensional geometry with the Homogeneous Equilibrium Model (HEM) may yield difficulties related to the very low sonic velocity associated with the HEM. These difficulties do not arise with subcritical flow. Possible solutions of the problem include introducing a relaxation of the vapor production rate. Three-dimensional simulations of subcooled boiling in bundle geometry typical of fast reactors can be performed by using two systems of conservation equations, one for the HEM and the other for a Separated Phases Model (SPM), with a smooth transition between the two models.

Bottoni, M.; Lyczkowski, R.; Ahuja, S.

1995-07-01T23:59:59.000Z

184

Neutron range spectrometer  

DOE Patents [OSTI]

A neutron range spectrometer and method for determining the neutron energy spectrum of a neutron emitting source are disclosed. Neutrons from the source are colliminated along a collimation axis and a position sensitive neutron counter is disposed in the path of the collimated neutron beam. The counter determines positions along the collimation axis of interactions between the neutrons in the neutron beam and a neutron-absorbing material in the counter. From the interaction positions, a computer analyzes the data and determines the neutron energy spectrum of the neutron beam. The counter is preferably shielded and a suitable neutron-absorbing material is He-3. 1 fig.

Manglos, S.H.

1988-03-10T23:59:59.000Z

185

RangeTables.xls  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -the Mid-Infrared at 278, 298, and 323Program2Raftopoulos(MeVcm²/mg) LET vs. Range

186

Long Range Development Plan  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6,Local Correlations andLocalThroughout theLong Range

187

Long Range Operations Schedule  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6,Local Correlations andLocalThroughout theLong Range7

188

Long Range Operations Schedule  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6,Local Correlations andLocalThroughout theLong Range78

189

A correlation for local coefficients of heat transfer in boiling of R12 and R22 refrigerants on multirow bundles of smooth tubes  

SciTech Connect (OSTI)

Experimental results on the boiling of R12 and R22 on bundles of 30 to 50 vertically stacked rows of smooth tubes are presented and correlated. Engineering equations for determining the coefficients of heat transfer in the pool boiling of freons on such multirow bundles are derived.

Rebrov, P.N.; Bukin, V.G.; Danilova, G.N.

1989-07-01T23:59:59.000Z

190

Reflectance Function Approximation for Material Classification  

E-Print Network [OSTI]

Reflectance Function Approximation for Material Classification Edward Wild CS 766 Final Project This report summarizes the results of a project to approximate reflectance functions and classify materials to classify materials. Classification algorithms are proposed to deal with unseen materials. Experimental

Dyer, Charles R.

191

ORIGINAL ARTICLE Approximate Truth and Descriptive Nesting  

E-Print Network [OSTI]

ORIGINAL ARTICLE Approximate Truth and Descriptive Nesting Jeffrey Alan Barrett Received: 7 July. This paper presents a notion of local probable approximate truth in terms of descriptive nesting relations

Barrett, Jeffrey A.

192

Fast Local Approximation to Global Illumination  

E-Print Network [OSTI]

based technique #12;Approach to Shadows · Assume: ­ Approximate shadow umbra with hard shadow ­ Object

Wyman, Chris

193

Kinetic Modeling and Thermodynamic Closure Approximation of ...  

E-Print Network [OSTI]

Oct 5, 2007 ... Kinetic Modeling and Thermodynamic Closure. Approximation of Liquid Crystal Polymers. Haijun Yu. Program in Applied and Computational ...

2007-10-03T23:59:59.000Z

194

Direct Observation of Born-Oppenheimer Approximation  

E-Print Network [OSTI]

Direct Observation of Born-Oppenheimer Approximation Breakdown in Carbon Nanotubes Adam W of the theoretically predicted breakdown of the Born-Oppenheimer approximation in individual single-walled carbon nanotubes. The Born-Oppenheimer (BO) or adiabatic approximation is widely used to simplify the very complex

Cronin, Steve

195

Mathematical Analysis of Born{Oppenheimer Approximations  

E-Print Network [OSTI]

Mathematical Analysis of Born{Oppenheimer Approximations George A. Hagedorn and Alain Joye concerning Born{Oppenheimer approximations in molecular quantum mechanics. Introduction The goal of this paper is to review rigorous mathematical results concerning Born{Oppenheimer approximations. We make

Hagedorn, George A.

196

IEEE TRANSACTIONS ON AUTOMATIC CONTROL, VOL. AC-20, NO. 6, DECEMBER 1975 127 Acoustics, Stability, and Compensation in Boiling  

E-Print Network [OSTI]

of turbine bypass valves duringstart-up as well asduringand following rapid closure of the turbine admissionIEEE TRANSACTIONS ON AUTOMATIC CONTROL, VOL. AC-20, NO. 6, DECEMBER 1975 127 Acoustics, Stability of steam pipe acoustics on the control of steam pressore in boiling waterreactors. A madel is developed

Kwatny, Harry G.

197

Microjet array single-phase and flow boiling heat transfer with R134a Eric A. Browne a  

E-Print Network [OSTI]

of a submerged microjet array was conducted with R134a. The staggered array of seventeen 112-lm diameter orifices blades and quench metals. Many of these practical uses of jets employ an array of jets rather than circular microjets of diameter 112 lm on a 1 Ã? 1 mm heater to investigate single-phase and boiling heat

Peles, Yoav

198

Boiling Water at Hot Creek--The Dangerous and Dynamic Thermal Springs in California's Long Valley Caldera  

E-Print Network [OSTI]

). Conditions in Hot Creek can change very quickly. These fish--caught in a burst of high-temperature water" or intermittently spurting very hot, sediment-laden water as high as 6 feet (2 m) above the stream surface. At timesBoiling Water at Hot Creek--The Dangerous and Dynamic Thermal Springs in California's Long Valley

Torgersen, Christian

199

Neutron range spectrometer  

DOE Patents [OSTI]

A neutron range spectrometer and method for determining the neutron energy spectrum of a neutron emitting source are disclosed. Neutrons from the source are collimnated along a collimation axis and a position sensitive neutron counter is disposed in the path of the collimated neutron beam. The counter determines positions along the collimation axis of interactions between the neutrons in the neutron beam and a neutron-absorbing material in the counter. From the interaction positions, a computer analyzes the data and determines the neutron energy spectrum of the neutron beam. The counter is preferably shielded and a suitable neutron-absorbing material is He-3. The computer solves the following equation in the analysis: ##EQU1## where: N(x).DELTA.x=the number of neutron interactions measured between a position x and x+.DELTA.x, A.sub.i (E.sub.i).DELTA.E.sub.i =the number of incident neutrons with energy between E.sub.i and E.sub.i +.DELTA.E.sub.i, and C=C(E.sub.i)=N .sigma.(E.sub.i) where N=the number density of absorbing atoms in the position sensitive counter means and .sigma. (E.sub.i)=the average cross section of the absorbing interaction between E.sub.i and E.sub.i +.DELTA.E.sub.i.

Manglos, Stephen H. (East Syracuse, NY)

1989-06-06T23:59:59.000Z

200

Experimental determination of residual stress by neutron diffraction in a boiling water reactor core shroud  

SciTech Connect (OSTI)

Residual strains in a 51 mm (2-inch) thick 304L stainless steel plate have been measured by neutron diffraction and interpreted in terms of residual stress. The plate, measuring (300 mm) in area, was removed from a 6m (20-ft.) diameter unirradiated boiling water reactor core shroud, and included a multiple-pass horizontal weld which joined two of the cylindrical shells which comprise the core shroud. Residual stress mapping was undertaken in the heat affected zone, concentrating on the outside half of the plate thickness. Variations in residual stresses with location appeared consistent with trends expected from finite element calculations, considering that a large fraction of the residual hoop stress was released upon removal of the plate from the core shroud cylinder.

Payzant, A.; Spooner, S.; Zhu, Xiaojing; Hubbard, C.R. [and others

1996-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "approximate boiling range" 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

Operational experience with and post-irradiation examinations on boiling water reactor control rods  

SciTech Connect (OSTI)

The control rods of the KRB-I 250-MW (electric) boiling water reactor contain Vipac B/sub 4/C powder in Type 304 stainless steel tubes as a neutron-absorbing material. Because of an increase in the reactor coolant /sup 3/H activity, defective control rods were suspected. The hot cell examination of a highly exposed control rod revealed B/sub 4/C losses. The mechanism of failure was shown to be B/sub 4/C swelling and stress corrosion cracking of the absorber tubes, followed by B/sub 4/C washout. The B/sub 4/C volume swelling is given. The tube cracking starts at 30 to 35% and the B/sub 4/C washout at 50 to 55% local /sup 10/B burnup in the tubes.

Eickelpash, N.; Mullauer, J.; Seepolt, R.W.; Spalthoff, W.

1983-03-01T23:59:59.000Z

202

Passive containment cooling system with drywell pressure regulation for boiling water reactor  

DOE Patents [OSTI]

A boiling water reactor is described having a regulating valve for placing the wetwell in flow communication with an intake duct of the passive containment cooling system. This subsystem can be adjusted to maintain the drywell pressure at (or slightly below or above) wetwell pressure after the initial reactor blowdown transient is over. This addition to the PCCS design has the benefit of eliminating or minimizing steam leakage from the drywell to the wetwell in the longer-term post-LOCA time period and also minimizes the temperature difference between drywell and wetwell. This in turn reduces the rate of long-term pressure buildup of the containment, thereby extending the time to reach the design pressure limit. 4 figures.

Hill, P.R.

1994-12-27T23:59:59.000Z

203

A phenomenological model of the thermal hydraulics of convective boiling during the quenching of hot rod bundles  

SciTech Connect (OSTI)

In this paper, a phenomenological model of the thermal hydraulics of convective boiling in the post-critical-heat-flux (post-CHF) regime is developed and discussed. The model was implemented in the TRAC-PF1/MOD2 computer code (an advanced best-estimate computer program written for the analysis of pressurized water reactor systems). The model was built around the determination of flow regimes downstream of the quench front. The regimes were determined from the flow-regime map suggested by Ishii and his coworkers. Heat transfer in the transition boiling region was formulated as a position-dependent model. The propagation of the CHF point was strongly dependent on the length of the transition boiling region. Wall-to-fluid film boiling heat transfer was considered to consist of two components: first, a wall-to-vapor convective heat-transfer portion and, second, a wall-to-liquid heat transfer representing near-wall effects. Each contribution was considered separately in each of the inverted annular flow (IAF) regimes. The interfacial heat transfer was also formulated as flow-regime dependent. The interfacial drag coefficient model upstream of the CHF point was considered to be similar to flow through a roughened pipe. A free-stream contribution was calculated using Ishii's bubbly flow model for either fully developed subcooled or saturated nucleate boiling. For the drag in the smooth IAF region, a simple smooth-tube correlation for the interfacial friction factor was used. The drag coefficient for the rough-wavy IAF was formulated in the same way as for the smooth IAF model except that the roughness parameter was assumed to be proportional to liquid droplet diameter entrained from the wavy interface. The drag coefficient in the highly dispersed flow regime considered the combined effects of the liquid droplets within the channel and a liquid film on wet unheated walls. 431 refs., 6 figs., 4 tabs.

Nelson, R.A.; Unal, C.

1991-01-01T23:59:59.000Z

204

APPROXIMATE HAMILTON DECOMPOSITIONS OF RANDOM FIACHRA KNOX, DANIELA KUHN AND DERYK OSTHUS  

E-Print Network [OSTI]

APPROXIMATE HAMILTON DECOMPOSITIONS OF RANDOM GRAPHS FIACHRA KNOX, DANIELA K¨UHN AND DERYK OSTHUS Abstract. We show that if pn log n the binomial random graph Gn,p has an approximate Hamilton decomposition. More precisely, we show that in this range Gn,p contains a set of edge-disjoint Hamilton cycles

Kühn, Daniela

205

Born-Oppenheimer approximation in open systems  

E-Print Network [OSTI]

We generalize the standard Born-Oppenheimer approximation to the case of open quantum systems. We define the zeroth order Born-Oppenheimer approximation of an open quantum system as the regime in which its effective Hamiltonian can be diagonalized with fixed slowly changing variables. We then establish validity and invalidity conditions for this approximation for two kinds of dissipations--the spin relaxation and the dissipation of center-of-mass motion. As an example, the Born-Oppenheimer approximation of a two-level open system is analyzed.

X. L. Huang; X. X. Yi

2009-09-16T23:59:59.000Z

206

Finite Element Approximation of Coupled Seismic and ...  

E-Print Network [OSTI]

numerical approximation of coupled seismic and electromagnetic waves in 2D bounded fluid- saturated porous media, with absorbing boundary conditions at ...

2009-02-15T23:59:59.000Z

207

Finite element approximation of coupled seismic and ...  

E-Print Network [OSTI]

layer, having a thickness of about 10 nm. Finite element approximation of coupled seismic and electromagnetic waves in gas hydrate-bearing sediments – p.

zyserman

208

A Characterization and Evaluation of Coal Liquefaction Process Streams. Results of Inspection Tests on Nine Coal-Derived Distillation Cuts in the Jet Fuel Boiling Range  

SciTech Connect (OSTI)

This report describes the assessment of the physical and chemical properties of the jet fuel (180-300 C) distillation fraction of nine direct coal liquefaction products and compares those properties to the corresponding specifications for aviation turbine fuels. These crude coal liquids were compared with finished fuel specifications specifically to learn what the refining requirements for these crudes will be to make them into finished fuels. The properties of the jet fuel fractions were shown in this work to require extensive hydrotreating to meet Jet A-1 specifications. However, these materials have a number of desirable qualities as feedstocks for the production of high energy-density jet fuels.

S. D. Brandes; R. A. Winschel

1999-12-30T23:59:59.000Z

209

Optimal Tree Approximation with Wavelets Richard Baraniuk  

E-Print Network [OSTI]

simply represented: the energy from a singularity localizes along one branch of the tree (see Figure 1Optimal Tree Approximation with Wavelets Richard Baraniuk Department of Electrical and Computer on trees and point out that an optimal tree approximant exists and is easily computed. The optimal tree

210

Approximate error conjugation gradient minimization methods  

DOE Patents [OSTI]

In one embodiment, a method includes selecting a subset of rays from a set of all rays to use in an error calculation for a constrained conjugate gradient minimization problem, calculating an approximate error using the subset of rays, and calculating a minimum in a conjugate gradient direction based on the approximate error. In another embodiment, a system includes a processor for executing logic, logic for selecting a subset of rays from a set of all rays to use in an error calculation for a constrained conjugate gradient minimization problem, logic for calculating an approximate error using the subset of rays, and logic for calculating a minimum in a conjugate gradient direction based on the approximate error. In other embodiments, computer program products, methods, and systems are described capable of using approximate error in constrained conjugate gradient minimization problems.

Kallman, Jeffrey S

2013-05-21T23:59:59.000Z

211

Design of a boiling water reactor equilibrium core using thorium-uranium fuel  

SciTech Connect (OSTI)

In this paper the design of a Boiling Water Reactor (BWR) equilibrium core using thorium is presented; a heterogeneous blanket-seed core arrangement concept was adopted. The design was developed in three steps: in the first step two different assemblies were designed based on the integrated blanket-seed concept, they are the blanket-dummy assembly and the blanket-seed assembly. The integrated blanketseed concept comes from the fact that the blanket and the seed rods are located in the same assembly, and are burned-out in a once-through cycle. In the second step, a core design was developed to achieve an equilibrium cycle of 365 effective full power days in a standard BWR with a reload of 104 fuel assemblies designed with an average 235U enrichment of 7.5 w/o in the seed sub-lattice. The main operating parameters, like power, linear heat generation rate and void distributions were obtained as well as the shutdown margin. It was observed that the analyzed parameters behave like those obtained in a standard BWR. The shutdown margin design criterion was fulfilled by addition of a burnable poison region in the assembly. In the third step an in-house code was developed to evaluate the thorium equilibrium core under transient conditions. A stability analysis was also performed. Regarding the stability analysis, five operational states were analyzed; four of them define the traditional instability region corner of the power-flow map and the fifth one is the operational state for the full power condition. The frequency and the boiling length were calculated for each operational state. The frequency of the analyzed operational states was similar to that reported for BWRs; these are close to the unstable region that occurs due to the density wave oscillation phenomena in some nuclear power plants. Four transient analyses were also performed: manual SCRAM, recirculation pumps trip, main steam isolation valves closure and loss of feed water. The results of these transients are similar to those obtained with the traditional UO2 nuclear fuel.

Francois, J-L.; Nunez-Carrera, A.; Espinosa-Paredes, G.; Martin-del-Campo, C.

2004-10-06T23:59:59.000Z

212

An investigation of the physical and numerical foundations of two-fluid representation of sodium boiling with applications to LMFBR experiments  

E-Print Network [OSTI]

This work involves the development of physical models for the constitutive relations of a two-fuid, three-dimensional sodium boiling code, THERMIT-6S. The code is equipped with a fluid conduction model, a fuel pin model, ...

No, Hee Cheon

1983-01-01T23:59:59.000Z

213

The effects of orientation angle, subcooling, heat flux, mass flux, and pressure on bubble growth and detachment in subcooled flow boiling  

E-Print Network [OSTI]

The effects of orientation angle, subcooling, heat flux, mass flux, and pressure on bubble growth and detachment in subcooled flow boiling were studied using a high-speed video camera in conjunction with a two-phase flow ...

Sugrue, Rosemary M

2012-01-01T23:59:59.000Z

214

Investigation of the pool boiling heat transfer enhancement of nano-engineered fluids by means of high-speed infrared thermography  

E-Print Network [OSTI]

A high-speed video and infrared thermography based technique has been used to obtain detailed and fundamental time- and space-resolved information on pool boiling heat transfer. The work is enabled by recent advances in ...

Gerardi, Craig Douglas

2009-01-01T23:59:59.000Z

215

Improved first order mean spherical approximation for simple fluids  

E-Print Network [OSTI]

A perturbation approach based on the first-order mean spherical approximation (FMSA) is proposed. It consists in adopting a hard-sphere plus short-range attractive Yukawa fluid as the novel reference system, over which the perturbative solution of the Ornstein-Zernike equation is performed. A choice of the optimal range of the reference attraction is discussed. The results are compared against conventional FMSA/HS theory and Monte-Carlo simulation data for compressibility factor and vapor-liquid phase diagrams of the medium-ranged Yukawa fluid. Proposed theory keeps the same level of simplicity and transparency, as the conventional FMSA/HS approach does, but shows to be more accurate.

S. Hlushak; A. Trokhymchuk; I. Nezbeda

2012-02-20T23:59:59.000Z

216

THORAX pretest prediction of a sodium-boiling transient in a 19-pin simulated LMFBR driver bundle  

SciTech Connect (OSTI)

Experiments will be conducted in the Thermal-Hydraulic Out-of-Reactor Safety-Shutdown Heat Removal System (THORS-SHRS) Assembly 1 loop at Oak Ridge National Laboratory (ORNL) to model the behavior of a reactor during degraded decay heat removal conditions. The test section is to consist of two parallel 19-pin electrically-heated driver bundles, typical of U.S. Large Developmental Plant (LDP) Liquid Metal Fast Breeder Reactor (LMFBR) design. Analysis of these experiments will include using THORAX, a two-dimensional boiling model which assumes an equilibrium mixture two-phase flow (with slip). A THORAX prediction is presented for a single-bundle forced convection boiling-to-dryout transient at 15.8 kW/pin.

Rose, S.D.

1982-01-01T23:59:59.000Z

217

Corrections to Eikonal Approximation for Nuclear Scattering at Medium Energies  

E-Print Network [OSTI]

The upcoming Facility for Rare Isotope Beams (FRIB) at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University has reemphasized the importance of accurate modeling of low energy nucleus-nucleus scattering. Such calculations have been simplified by using the eikonal approximation. As a high energy approximation, however, its accuracy suffers for the medium energy beams that are of current experimental interest. A prescription developed by Wallace \\cite{Wallace:1971zz,Wallace:1973iu} that obtains the scattering propagator as an expansion around the eikonal propagator (Glauber approach) has the potential to extend the range of validity of the approximation to lower energies. Here we examine the properties of this expansion, and calculate the first-, second-, and third-order corrections for the scattering of a spinless particle off of a ${}^{40}$Ca nucleus, and for nuclear breakup reactions involving ${}^{11}$Be. We find that, including these corrections extends the lower bound of the range of validity of the down to energies of 40 MeV. At that energy the corrections provide as much as a 15\\% correction to certain processes.

Micah Buuck; Gerald A. Miller

2014-06-12T23:59:59.000Z

218

Study of plutonium disposition using existing GE advanced Boiling Water Reactors  

SciTech Connect (OSTI)

The end of the cold war and the resulting dismantlement of nuclear weapons has resulted in the need for the US to dispose of 50 to 100 metric tons of excess of plutonium in a safe and proliferation resistant manner. A number of studies, including the recently released National Academy of Sciences (NAS) study, have recommended conversion of plutonium into spent nuclear fuel with its high radiation barrier as the best means of providing permanent conversion and long-term diversion resistance to this material. The NAS study ``Management and Disposition of Excess Weapons Plutonium identified Light Water Reactor spent fuel as the most readily achievable and proven form for the disposition of excess weapons plutonium. The study also stressed the need for a US disposition program which would enhance the prospects for a timely reciprocal program agreement with Russia. This summary provides the key findings of a GE study where plutonium is converted into Mixed Oxide (MOX) fuel and a typical 1155 MWe GE Boiling Water Reactor (BWR) is utilized to convert the plutonium to spent fuel. A companion study of the Advanced BWR has recently been submitted. The MOX core design work that was conducted for the ABWR enabled GE to apply comparable fuel design concepts and consequently achieve full MOX core loading which optimize plutonium throughput for existing BWRs.

Not Available

1994-06-01T23:59:59.000Z

219

The Neutronics Design and Analysis of a 200-MW(electric) Simplified Boiling Water Reactor Core  

SciTech Connect (OSTI)

A 200-MW(electric) simplified boiling water reactor (SBWR) was designed and analyzed under sponsorship of the U.S. Department of Energy Nuclear Energy Research Initiative program. The compact size of a 200-MW(electric) reactor makes it attractive for countries with a less well developed engineering infrastructure, as well as for developed countries seeking to tailor generation capacity more closely to the growth of their electricity demand. The 200-MW(electric) core design reported here is based on the 600-MW(electric) General Electric SBWR core, which was first analyzed in the work performed here in order to qualify the computer codes used in the analysis. Cross sections for the 8 x 8 fuel assembly design were generated with the HELIOS lattice physics code, and core simulation was performed with the U.S. Nuclear Regulatory Commission codes RELAP5/PARCS. In order to predict the critical heat flux, the Hench-Gillis correlation was implemented in the RELAP5 code. An equilibrium cycle was designed for the 200-MW(electric) core, which provided a cycle length of more than 2 yr and satisfied the minimum critical power ratio throughout the core life.

Tinkler, Daniel R.; Downar, Thomas J. [Purdue University (United States)

2003-06-15T23:59:59.000Z

220

FORMOSA-B: A Boiling Water Reactor In-Core Fuel Management Optimization Package II  

SciTech Connect (OSTI)

As part of the continuing development of the boiling water reactor in-core fuel management optimization code FORMOSA-B, the fidelity of the core simulator has been improved and a control rod pattern (CRP) sampling capability has been added. The robustness of the core simulator is first demonstrated by benchmarking against core load-follow depletion predictions of both SIMULATE-3 and MICROBURN-B2 codes. The CRP sampling capability, based on heuristic rules, is next successfully tested on a fixed fuel loading pattern (LP) to yield a feasible CRP that removes the thermal margin and critical flow constraint violations. Its performance in facilitating a spectral shift flow operation is also demonstrated, and then its significant influence on the cost of thermal margin is presented. Finally, the heuristic CRP sampling capability is coupled with the stochastic LP optimization capability in FORMOSA-B - based on simulated annealing (SA) - to solve the combined CRP-LP optimization problem. Effectiveness of the sampling in improving the efficiency of the SA adaptive algorithm is shown by comparing the results to those obtained with the sampling turned off (i.e., only LP optimization is carried out for the fixed reference CRP). The results presented clearly indicate the successful implementation of the CRP sampling algorithm and demonstrate FORMOSA-B's enhanced optimization features, which facilitate the code's usage for broader optimization studies.

Karve, Atul A.; Turinsky, Paul J. [North Carolina State University (United States)

2000-07-15T23:59:59.000Z

Note: This page contains sample records for the topic "approximate boiling range" 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

Results of the DF-4 BWR (boiling water reactor) control blade-channel box test  

SciTech Connect (OSTI)

The DF-4 in-pile fuel damage experiment investigated the behavior of boiling water reactor (BWR) fuel canisters and control blades in the high temperature environment of an unrecovered reactor accident. This experiment, which was carried out in the Annular Core Research Reactor (ACRR) at Sandia National Laboratories, was performed under the USNRC's internationally sponsored severe fuel damage (SFD) program. The DF-4 test is described herein and results from the experiment are presented. Important findings from the DF-4 test include the low temperature melting of the stainless steel control blade caused by reaction with the B{sub 4}C, and the subsequent low temperature attack of the Zr-4 channel box by the relocating molten blade components. Hydrogen generation was found to continue throughout the experiment, diminishing slightly following the relocation of molten oxidizing zircaloy to the lower extreme of the test bundle. A large blockage which was formed from this material continued to oxidize while steam was being fed into the the test bundle. The results of this test have provided information on the initial stages of core melt progression in BWR geometry involving the heatup and cladding oxidation stages of a severe accident and terminating at the point of melting and relocation of the metallic core components. The information is useful in modeling melt progression in BWR core geometry, and provides engineering insight into the key phenomena controlling these processes. 12 refs., 12 figs.

Gauntt, R.O.; Gasser, R.D.

1990-10-01T23:59:59.000Z

222

Operational experience with and postirradiation examinations on boiling water reactor control rods  

SciTech Connect (OSTI)

The control rods of the KRBI-I 250-MW(electric) boiling water reactor contain Vipac B/sub 4/C powder in Type 304 stainless steel tubes as a neutron-absorbing material. Because of an increase in the reactor coolant /sup 3/H activity, defective control rods were suspected. The hot cell examination of a highly exposed control rod revealed B/sub 4/C losses. The mechanism of failure was shown to be B/sub 4/C swelling and stress corrosion cracking of the absorber tubes, followed by B/sub 4/C washout. The B/sub 4/C volume swelling is ..delta..V(%) = 0.851x + 0.0449x/sup 2/ (x = /sup 10/B decays in 10/sup 21/(n,..cap alpha..)/cm/sup 3/). The tube cracking starts at 30 to 35% and the B/sub 4/C washout at 50 to 55% local /sup 10/B burnup in the tubes.

Eickelpasch, N.; Seepolt, R.W.; Muellauer, J.; Spalthoff, W.

1983-03-01T23:59:59.000Z

223

Enhancement of Heat Transfer with Pool and Spray Impingement Boiling on Microporous and Nanowire Surface Coatings  

SciTech Connect (OSTI)

The DOE National Renewable Energy Laboratory (NREL) is leading a national effort to develop next-generation cooling technologies for hybrid vehicle electronics. The goal is to reduce the size, weight, and cost of power electronic modules that convert direct current from batteries to alternating current for the motor, and vice versa. Aggressive thermal management techniques help to increase power density and reduce weight and volume, while keeping chip temperatures within acceptable limits. The viability of aggressive cooling schemes such as spray and jet impingement in conjunction with enhanced surfaces is being explored. Here, we present results from a series of experiments with pool and spray boiling on enhanced surfaces, such as a microporous layer of copper and copper nanowires, using HFE-7100 as the working fluid. Spray impingement on the microporous coated surface showed an enhancement of 100%-300% in the heat transfer coefficient at a given wall superheat with respect to spray impingement on a plain surface under similar operating conditions. Critical heat flux also increased by 7%-20%, depending on flow rates.

Thiagarajan, S. J.; Wang, W.; Yang, R.; Narumanchi, S.; King, C.

2010-09-01T23:59:59.000Z

224

Decontamination and decommissioning of the Experimental Boiling Water Reactor (EBWR): Project final report, Argonne National Laboratory  

SciTech Connect (OSTI)

The Final Report for the Decontamination and Decommissioning (D&D) of the Argonne National Laboratory - East (ANL-E) Experimental Boiling Water Reactor (EBWR) facility contains the descriptions and evaluations of the activities and the results of the EBWR D&D project. It provides the following information: (1) An overall description of the ANL-E site and EBWR facility. (2) The history of the EBWR facility. (3) A description of the D&D activities conducted during the EBWR project. (4) A summary of the final status of the facility, including the final and confirmation surveys. (5) A summary of the final cost, schedule, and personnel exposure associated with the project, including a summary of the total waste generated. This project report covers the entire EBWR D&D project, from the initiation of Phase I activities to final project closeout. After the confirmation survey, the EBWR facility was released as a {open_quotes}Radiologically Controlled Area,{close_quotes} noting residual elevated activity remains in inaccessible areas. However, exposure levels in accessible areas are at background levels. Personnel working in accessible areas do not need Radiation Work Permits, radiation monitors, or other radiological controls. Planned use for the containment structure is as an interim transuranic waste storage facility (after conversion).

Fellhauer, C.R.; Boing, L.E. [Argonne National Lab., IL (United States); Aldana, J. [NES, Inc., Danbury, CT (United States)

1997-03-01T23:59:59.000Z

225

Quasielastic electron-deuteron scattering in the weak binding approximation  

SciTech Connect (OSTI)

We perform a global analysis of all available electron-deuteron quasielastic scattering data using Q^2-dependent smearing functions that describe inclusive inelastic e-d scattering within the weak binding approximation. We study the dependence of the cross sections on the deuteron wave function and the off-shell extrapolation of the elastic electron-nucleon cross section, which show particular sensitivity at x >> 1. The excellent overall agreement with data over a large range of Q^2 and x suggest a limited need for effects beyond the impulse approximation, with the exception of the very high-x or very low-Q^2 regions, where short-distance effects in the deuteron become more relevant.

Ethier, Jacob J. [William and Mary College, JLAB; Doshi, Nidhi P. [Carnegie Mellon University; Malace, Simona P. [JLAB; Melnitchouk, Wally [JLAB

2014-06-01T23:59:59.000Z

226

Approximate Bivariate Factorization, a Geometric Andre Galligo  

E-Print Network [OSTI]

INRIA) Laboratoire de Mathematiques Parc Valrose 06108 Nice cedex 02, France galligo@unice.fr Mark van, Maple Code 1. INTRODUCTION 1.1 Approximate algebra Over the past ten years symbolic-numeric algorithms

Hoeij, Mark van

227

Optimization in Geometric Graphs: Complexity and Approximation  

E-Print Network [OSTI]

We consider several related problems arising in geometric graphs. In particular, we investigate the computational complexity and approximability properties of several optimization problems in unit ball graphs and develop algorithms to find exact...

Kahruman-Anderoglu, Sera

2011-02-22T23:59:59.000Z

228

Hardness of approximation for quantum problems  

E-Print Network [OSTI]

The polynomial hierarchy plays a central role in classical complexity theory. Here, we define a quantum generalization of the polynomial hierarchy, and initiate its study. We show that not only are there natural complete problems for the second level of this quantum hierarchy, but that these problems are in fact hard to approximate. Using these techniques, we also obtain hardness of approximation for the class QCMA. Our approach is based on the use of dispersers, and is inspired by the classical results of Umans regarding hardness of approximation for the second level of the classical polynomial hierarchy [Umans, FOCS 1999]. The problems for which we prove hardness of approximation for include, among others, a quantum version of the Succinct Set Cover problem, and a variant of the local Hamiltonian problem with hybrid classical-quantum ground states.

Sevag Gharibian; Julia Kempe

2012-09-05T23:59:59.000Z

229

Approximation algorithms for QMA-complete problems  

E-Print Network [OSTI]

Approximation algorithms for classical constraint satisfaction problems are one of the main research areas in theoretical computer science. Here we define a natural approximation version of the QMA-complete local Hamiltonian problem and initiate its study. We present two main results. The first shows that a non-trivial approximation ratio can be obtained in the class NP using product states. The second result (which builds on the first one), gives a polynomial time (classical) algorithm providing a similar approximation ratio for dense instances of the problem. The latter result is based on an adaptation of the "exhaustive sampling method" by Arora et al. [J. Comp. Sys. Sci. 58, p.193 (1999)] to the quantum setting, and might be of independent interest.

Sevag Gharibian; Julia Kempe

2011-01-20T23:59:59.000Z

230

Optimization Online - An Approximation Algorithm for Constructing ...  

E-Print Network [OSTI]

Sep 2, 2006 ... In this paper, we propose an approximation algorithm for the 2-bit Hamming prefix code problem. Our algorithm spends $O(n \\log^3 n)$ time to ...

Artur Pessoa

2006-09-02T23:59:59.000Z

231

RESTRICTED-TRACE APPROXIMATION FOR NUCLEAR ANTIFERROMAGNETISM  

E-Print Network [OSTI]

1353 RESTRICTED-TRACE APPROXIMATION FOR NUCLEAR ANTIFERROMAGNETISM M. GOLDMAN and G. SARMA Service to predict several properties of nuclear antiferromagnetic structures : sublattice magnetization of nuclear dipolar magnetic ordering, either antiferromagnetic or ferromagnetic, has been reported

Boyer, Edmond

232

A fresh look at the adhesion approximation  

E-Print Network [OSTI]

I report on a systematic derivation of the phenomenological ``adhesion approximation'' from gravitational instability together with a brief evaluation of the related status of analytical modeling of large-scale structure.

Thomas Buchert

1997-11-04T23:59:59.000Z

233

Harmonic Wavelet Transform and Image Approximation  

E-Print Network [OSTI]

DOI 10.1007/s10851-010-0202-x Harmonic Wavelet Transform andwe approximate f by a harmonic function u such that thebanks. We call this the Harmonic Wavelet Transform (HWT).

Zhang, Zhihua; Saito, Naoki

2010-01-01T23:59:59.000Z

234

The effect of surface conditions on nuceate pool boiling heat transfer to sodium  

E-Print Network [OSTI]

A simplified theoretical model for bubble nucleation stability has been proposed, and an approximate stability criterion has been developed. This criterion contains both fluid and surfqce properties, and it predicts that ...

Marto, P. J.

1965-01-01T23:59:59.000Z

235

Compton scattering from positronium and validity of the impulse approximation  

SciTech Connect (OSTI)

The cross sections for Compton scattering from positronium are calculated in the range from 1 to 100 keV incident photon energy. The calculations are based on the A{sup 2} term of the photon-electron or photon-positron interaction. Unlike in hydrogen, the scattering occurs from two centers and the interference effect plays an important role for energies below 8 keV. Because of the interference, the criterion for validity of the impulse approximation for positronium is more restrictive compared to that for hydrogen.

Kaliman, Z.; Pisk, K.; Pratt, R. H. [Department of Physics, University of Rijeka, Rijeka (Croatia); Rudjer Boskovic Institute, P. O. Box 180, Zagreb (Croatia) and University of Dubrovnik, Dubrovnik (Croatia); Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260 (United States)

2011-05-15T23:59:59.000Z

236

Study of plutonium disposition using the GE Advanced Boiling Water Reactor (ABWR)  

SciTech Connect (OSTI)

The end of the cold war and the resulting dismantlement of nuclear weapons has resulted in the need for the U.S. to disposition 50 to 100 metric tons of excess of plutonium in parallel with a similar program in Russia. A number of studies, including the recently released National Academy of Sciences (NAS) study, have recommended conversion of plutonium into spent nuclear fuel with its high radiation barrier as the best means of providing long-term diversion resistance to this material. The NAS study {open_quotes}Management and Disposition of Excess Weapons Plutonium{close_quotes} identified light water reactor spent fuel as the most readily achievable and proven form for the disposition of excess weapons plutonium. The study also stressed the need for a U.S. disposition program which would enhance the prospects for a timely reciprocal program agreement with Russia. This summary provides the key findings of a GE study where plutonium is converted into Mixed Oxide (MOX) fuel and a 1350 MWe GE Advanced Boiling Water Reactor (ABWR) is utilized to convert the plutonium to spent fuel. The ABWR represents the integration of over 30 years of experience gained worldwide in the design, construction and operation of BWRs. It incorporates advanced features to enhance reliability and safety, minimize waste and reduce worker exposure. For example, the core is never uncovered nor is any operator action required for 72 hours after any design basis accident. Phase 1 of this study was documented in a GE report dated May 13, 1993. DOE`s Phase 1 evaluations cited the ABWR as a proven technical approach for the disposition of plutonium. This Phase 2 study addresses specific areas which the DOE authorized as appropriate for more in-depth evaluations. A separate report addresses the findings relative to the use of existing BWRs to achieve the same goal.

NONE

1994-04-30T23:59:59.000Z

237

Extended range chemical sensing apparatus  

DOE Patents [OSTI]

An apparatus is described for sensing chemicals over extended range of concentrations. In particular, first and second sensors each having separate, but overlapping ranges for sensing concentrations of hydrogen are provided. Preferably, the first sensor is a MOS solid state device wherein the metal electrode or gate is a nickel alloy. The second sensor is a chemiresistor comprising a nickel alloy. 6 figures.

Hughes, R.C.; Schubert, W.K.

1994-01-18T23:59:59.000Z

238

MODULAR AND FULL SIZE SIMPLIFIED BOILING WATER REACTOR DESIGN WITH FULLY PASSIVE SAFETY SYSTEMS  

SciTech Connect (OSTI)

OAK B204 The overall goal of this three-year research project was to develop a new scientific design of a compact modular 200 MWe and a full size 1200 MWe simplified boiling water reactors (SBWR). Specific objectives of this research were: (1) to perform scientific designs of the core neutronics and core thermal-hydraulics for a small capacity and full size simplified boiling water reactor, (2) to develop a passive safety system design, (3) improve and validate safety analysis code, (4) demonstrate experimentally and analytically all design functions of the safety systems for the design basis accidents (DBA) and (5) to develop the final scientific design of both SBWR systems, 200 MWe (SBWR-200) and 1200 MWe (SBWR-1200). The SBWR combines the advantages of design simplicity and completely passive safety systems. These advantages fit well within the objectives of NERI and the Department of Energy's focus on the development of Generation III and IV nuclear power. The 3-year research program was structured around seven tasks. Task 1 was to perform the preliminary thermal-hydraulic design. Task 2 was to perform the core neutronic design analysis. Task 3 was to perform a detailed scaling study and obtain corresponding PUMA conditions from an integral test. Task 4 was to perform integral tests and code evaluation for the DBA. Task 5 was to perform a safety analysis for the DBA. Task 6 was to perform a BWR stability analysis. Task 7 was to perform a final scientific design of the compact modular SBWR-200 and the full size SBWR-1200. A no cost extension for the third year was requested and the request was granted and all the project tasks were completed by April 2003. The design activities in tasks 1, 2, and 3 were completed as planned. The existing thermal-hydraulic information, core physics, and fuel lattice information was collected on the existing design of the simplified boiling water reactor. The thermal-hydraulic design were developed. Based on a detailed integral system scaling analysis, design parameters were obtained and designs of the compact modular 200 MWe SBWR and the full size 1200 MWe SBWR were developed. These reactors are provided with passive safety systems. A new passive vacuum breaker check valve was designed to replace the mechanical vacuum beaker check valve. The new vacuum breaker check valve was based on a hydrostatic head, and was fail safe. The performance of this new valve was evaluated both by the thermal-hydraulic code RELAP5 and by the experiments in a scaled SBWR facility, PUMA. In the core neutronic design a core depletion model was implemented to PARCS code. A lattice design for the SBWR fuel assemblies was performed. Design improvements were made to the neutronics/thermal-hydraulics models of SBWR-200 and SBWR-1200, and design analyses of these reactors were performed. The design base accident analysis and evaluation of all the passive safety systems were completed as scheduled in tasks 4 and 5. Initial conditions for the small break loss of coolant accidents (LOCA) and large break LOCA using REALP5 code were obtained. Small and large break LOCA tests were performed and the data was analyzed. An anticipated transient with scram was simulated using the RELAP5 code for SBWR-200. The transient considered was an accidental closure of the main steam isolation valve (MSIV), which was considered to be the most significant transient. The evaluation of the RELAP5 code against experimental data for SBWR-1200 was completed. In task 6, the instability analysis for the three SBWR designs (SBWR-1200, SBWR-600 and SBWR-200) were simulated for start-up transients and the results were similar. Neither the geysering instability, nor the loop type instability was predicted by RAMONA-4B in the startup simulation following the recommended procedure by GE. The density wave oscillation was not observed at all because the power level used in the simulation was not high enough. A study was made of the potential instabilities by imposing an unrealistically high power ramp in a short time period, as suggested by GE. RAMON

M. Ishii; S. T. Revankar; T. Downar; Y. Xu, H. J. Yoon; D. Tinkler; U. S. Rohatgi

2003-06-16T23:59:59.000Z

239

Formalising the Slow-Roll Approximation in Inflation  

E-Print Network [OSTI]

The meaning of the inflationary slow-roll approximation is formalised. Comparisons are made between an approach based on the Hamilton-Jacobi equations, governing the evolution of the Hubble parameter, and the usual scenario based on the evolution of the potential energy density. The vital role of the inflationary attractor solution is emphasised, and some of its properties described. We propose a new measure of inflation, based upon contraction of the comoving Hubble length as opposed to the usual e-foldings of physical expansion, and derive relevant formulae. We introduce an infinite hierarchy of slow-roll parameters, and show that only a finite number of them are required to produce results to a given order. The extension of the slow-roll approximation into an analytic slow-roll expansion, converging on the exact solution, is provided. Its role in calculations of inflationary dynamics is discussed. We explore rational-approximants as a method of extending the range of convergence of the slow-roll expansion up to, and beyond, the end of inflation.

Andrew R. Liddle; Paul Parsons; John D. Barrow

1994-08-04T23:59:59.000Z

240

Approximate Killing Fields as an Eigenvalue Problem  

E-Print Network [OSTI]

Approximate Killing vector fields are expected to help define physically meaningful spins for non-symmetric black holes in general relativity. However, it is not obvious how such fields should be defined geometrically. This paper relates a definition suggested recently by Cook and Whiting to an older proposal by Matzner, which seems to have been overlooked in the recent literature. It also describes how to calculate approximate Killing fields based on these proposals using an efficient scheme that could be of immediate practical use in numerical relativity.

Christopher Beetle

2008-08-12T23:59:59.000Z

Note: This page contains sample records for the topic "approximate boiling range" 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

Stochastic Approximation and Its Application in MCMC  

E-Print Network [OSTI]

) is known as observational noise, which is de ned as follows: t+1 = H t+1( t; xt+1) h t+1( t); In 1951, Robin and Monro introduced the so-called Robbins - Monro algorithm (1951) to solve the integration equation and the algorithm works as follows...: Algorithm 1.1.1. Stochastic Approximation 1 a. Generate Xt+1 g t(x), where t indexes the iteration. b. Set t+1 = t + atH( t; Xt+1), where at is the gain factor. This Robbins a^ Monro algorithm is the most popular stochastic approximation method used...

Cheng, Yichen

2013-05-31T23:59:59.000Z

242

Realizing Physical Approximation of the Partial Transpose  

E-Print Network [OSTI]

The partial transpose by which a subsystem's quantum state is solely transposed is of unique importance in quantum information processing from both fundamental and practical point of view. In this work, we present a practical scheme to realize a physical approximation to the partial transpose using local measurements on individual quantum systems and classical communication. We then report its linear optical realization and show that the scheme works with no dependence on local basis of given quantum states. A proof-of-principle demonstration of entanglement detection using the physical approximation of the partial transpose is also reported.

Hyang-Tag Lim; Yong-Su Kim; Young-Sik Ra; Joonwoo Bae; Yoon-Ho Kim

2011-04-18T23:59:59.000Z

243

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

244

IPA Extensions Range: 025002AF  

E-Print Network [OSTI]

IPA Extensions Range: 0250­02AF This file contains an excerpt from the character code tables 0268IPA Extensions0250 025B LATIN SMALL LETTER OPEN E = LATIN SMALL LETTER EPSILON · lower-mid front

Erjavec, TomaÂ?

245

Kirchhoff approximation for diffusive waves Jorge Ripoll*  

E-Print Network [OSTI]

Laboratoire d'Energetique Moleculaire et Macroscopique, Combustion, Ecole Centrale Paris, Centre National de for accurately solving the direct scattering problem 17,18,23 for arbitrary geometries, but these methods,26 . This approximation is a linear method that does not involve matrix inversion while solving the forward problem

Lorenzo, Jorge Ripoll

246

Correcting the diffusion approximation at the boundary  

E-Print Network [OSTI]

, 2011 The diffusion approximation to the radiative transport equation applies for light that has solutions of the radiative transport equation to evaluate each of their accuracy. Nonetheless, nearly all transport equation · I þ aI þ sLI ¼ 0; ð1:1� governs continuous light propagation in tissues [1

Kim, Arnold D.

247

IMPROVING THE APPROXIMATION AND CONVERGENCE CAPABILITIES OF  

E-Print Network [OSTI]

­dimensional data. Projection pursuit learning (PPL) formulates PPR in a neural network framework. One major difference between PPR and PPL is that the smoothers in PPR are nonparametric, whereas those in PPL are based known, we demonstrate that PPL networks do not have the universal approximation and strong convergence

Yeung, Dit-Yan

248

Approximating the Permanent with Belief Propagation  

E-Print Network [OSTI]

, then use Bethe free energy to approximate this partition function. After deriving some speedups to standard, not to mention relatively high polynomial running times that discourage their usage in practical applications-connected networks such as trees. In certain special loopy graph cases, including graphs with a single loop

Huang, Bert

249

Blind Channel Equalization and -Approximation Algorithms  

E-Print Network [OSTI]

Blind Channel Equalization and #15;-Approximation Algorithms #3; Qingyu Li 1 , Er-Wei Bai 1 University of Iowa Iowa City, IA 52242 Abstract In this paper, we show that a blind equalizer can be obtained without using any sta- tistical information on the input by formulating the blind channel equalization

Ye, Yinyu

250

FRACTAL APPROXIMATION AND COMPRESSION USING PROJECTED IFS  

E-Print Network [OSTI]

FRACTAL APPROXIMATION AND COMPRESSION USING PROJECTED IFS �ric Guérin, �ric Tosan and Atilla, or images) with fractal models is an important center of interest for research. The general inverse problem.The most known of them is the fractal image compression method introduced by Jacquin. Generally speaking

Baskurt, Atilla

251

APPROXIMATION ALGORITHMS FOR SCHEDULING a dissertation  

E-Print Network [OSTI]

Approved for the University Committee on Graduate Studies: iii #12; iv #12; Abstract This thesis describes instance of the problem, returns a solution whose value is within some guaranteed multiplicative factor ff release dates only we obtain an e e\\Gamma1 ' 1:58 approximation. For the parallel machine case we obtain

Chekuri, Chandra

252

Symbolic Test Selection Based on Approximate Analysis  

E-Print Network [OSTI]

Symbolic Test Selection Based on Approximate Analysis Bertrand Jeannet, Thierry J´eron, Vlad Rusu}@irisa.fr Abstract. This paper addresses the problem of generating symbolic test cases for testing the conformance. The challenge we consider is the selection of test cases according to a test purpose, which is here a set

Paris-Sud XI, Université de

253

Approximate Inference and Protein-Folding  

E-Print Network [OSTI]

Approximate Inference and Protein-Folding Chen Yanover and Yair Weiss School of Computer Science Side-chain prediction is an important subtask in the protein-folding problem. We show that #12;nding algorithms, including a widely used protein-folding software (SCWRL). 1 Introduction Inference in graphical

Weiss, Yair

254

Vibrational Superposition States Without Rotating Wave Approximation  

E-Print Network [OSTI]

We propose a scheme to generate superpositions of coherent states for the vibrational motion of a laser cooled trapped-ion. It is based on the interaction with a standing wave making use of the counter-rotating terms, i.e. not applying the rotating wave approximation. We also show that the same scheme can be exploited for quantum state measurement, i.e. with the same scheme non-classical states may be reconstructed

Mancini, S; Tombesi, P

2000-01-01T23:59:59.000Z

255

Final safety evaluation report related to the certification of the advanced boiling water reactor design. Volume 2: Appendices  

SciTech Connect (OSTI)

This safety evaluation report (SER) documents the technical review of the US Advanced Boiling Water Reactor (ABWR) standard design by the US Nuclear Regulatory Commission (NRC) staff. The application for the ABWR design was initially submitted by the General Electric Company, now GE Nuclear Energy (GE), in accordance with the procedures of Appendix O of Part 50 of Title 10 of the code of Federal Regulations (10 CFR Part 50). Later GE requested that its application be considered as an application for design approval and subsequent design certification pursuant to 10 CFR {section} 52.45. The ABWR is a single-cycle, forced-circulation, boiling water reactor (BWR) with a rated power of 3,926 megawatts thermal (MWt) and a design power of 4,005 MWt. To the extent feasible and appropriate, the staff relied on earlier reviews for those ABWR design features that are substantially the same as those previously considered. Unique features of the ABWR design include internal recirculation pumps, fine-motion control rod drives, microprocessor-based digital logic and control systems, and digital safety systems. On the basis of its evaluation and independent analyses, the NRC staff concludes that, subject to satisfactory resolution of the confirmatory items identified in Section 1.8 of this SER, GE`s application for design certification meets the requirements of Subpart B of 10 CFR Part 52 that are applicable and technically relevant to the US ABWR standard design.

Not Available

1994-07-01T23:59:59.000Z

256

Final safety evaluation report related to the certification of the advanced boiling water reactor design. Volume 1: Main report  

SciTech Connect (OSTI)

This safety evaluation report (SER) documents the technical review of the US Advanced Boiling Water Reactor (ABWR) standard design by the US Nuclear Regulatory Commission (NRC) staff. The application for the ABWR design was initially submitted by the General Electric Company, now GE Nuclear Energy (GE), in accordance with the procedures of Appendix O of Part 50 of Title 10 of the Code of Federal Regulations (10 CFR Part 50). Later GE requested that its application be considered as an application for design approval and subsequent design certification pursuant to 10 CFR {section} 52.45. The ABWR is a single-cycle, forced-circulation, boiling water reactor (BWR) with a rated power of 3,926 megawatts thermal (MWt) and a design power of 4,005 MWt. To the extent feasible and appropriate, the staff relied on earlier reviews for those ABWR design features that are substantially the same as those previously considered. Unique features of the ABWR design include internal recirculation pumps, fine-motion control rod drives, microprocessor-based digital logic and control systems, and digital safety systems. On the basis of its evaluation and independent analyses, the NRC staff concludes that, subject to satisfactory resolution of the confirmatory items identified in Section 1.8 of this SER, GE`s application for design certification meets the requirements of Subpart B of 10 CFR Part 52 that are applicable and technically relevant to the US ABWR standard design.

Not Available

1994-07-01T23:59:59.000Z

257

Dispersed-flow film boiling in rod-bundle geometry: steady-state heat-transfer data and correlation comparisons. [PWR; BWR  

SciTech Connect (OSTI)

Assessment of six film boiling correlations and one single-phase vapor correlation has been made using data from 22 steady state upflow rod bundle tests (series 3.07.9). Bundle fluid conditions were calculated using energy and mass conservation considerations. Results of the steady state film boiling tests support the conclusions reached in the analysis of prior transient tests 3.03.6AR, 3.06.6B, and 3.08.6C. Comparisons between experimentally determined and correlation-predicted heat transfer coefficients, are presented.

Yoder, G. L.; Morris, D. G.; Mullins, C. B.; Ott, L. J.; Reed, D. A.

1982-03-01T23:59:59.000Z

258

Knapsack Problems with Sigmoid Utilities: Approximation Algorithms via Hybrid Optimization$  

E-Print Network [OSTI]

Knapsack Problems with Sigmoid Utilities: Approximation Algorithms via Hybrid Optimization$ Vaibhav with sigmoid utilities. We merge approximation algorithms from discrete optimization with algorithms from continuous optimization to develop approximation algorithms for these NP-hard problems with sigmoid utilities

Bullo, Francesco

259

PACIFIC SOUTHWEST Forest and Range  

E-Print Network [OSTI]

of forest stands is valuable for studies of the physical environment. Energy balance research centers on howPACIFIC SOUTHWEST Forest and Range Experiment Station FOREST SERVICE U.S. DEPARTMENT in relation to climatic and stand variables USDA FOREST SERVICE RESEARCH PAPER PSW- 71 /1971 #12;CONTENTS

Standiford, Richard B.

260

PACIFIC SOUTHWEST Forest and Range  

E-Print Network [OSTI]

C. Hathaway, both of the Black Hills National Forest, Custer, South Dakota, provided the necessaryPACIFIC SOUTHWEST Forest and Range FOREST SERVICE U. S.DEPARTMENT OF AGRICULTURE P.O. BOX 245, BERKELEY, CALIFORNIA 94701 Experiment Station USDA FOREST SERVICE RESEARCH PAPER PSW- 96 /1973 #12;CONTENTS

Standiford, Richard B.

Note: This page contains sample records for the topic "approximate boiling range" 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

Pacific Southwest Forest and Range  

E-Print Network [OSTI]

. MCKETTA is an economist with the College of Forestry, Wildlife, and Range Sciences, University of Idaho has been developed for determining the cost of Fire Management Inputs (FMls)-the direct frreline costs, economic costs, fire economics, suppression costs, Fire Economics Evaluation System (FEES

Standiford, Richard B.

262

Communication: Random phase approximation renormalized many-body perturbation theory  

SciTech Connect (OSTI)

We derive a renormalized many-body perturbation theory (MBPT) starting from the random phase approximation (RPA). This RPA-renormalized perturbation theory extends the scope of single-reference MBPT methods to small-gap systems without significantly increasing the computational cost. The leading correction to RPA, termed the approximate exchange kernel (AXK), substantially improves upon RPA atomization energies and ionization potentials without affecting other properties such as barrier heights where RPA is already accurate. Thus, AXK is more balanced than second-order screened exchange [A. Grüneis et al., J. Chem. Phys. 131, 154115 (2009)], which tends to overcorrect RPA for systems with stronger static correlation. Similarly, AXK avoids the divergence of second-order Møller-Plesset (MP2) theory for small gap systems and delivers a much more consistent performance than MP2 across the periodic table at comparable cost. RPA+AXK thus is an accurate, non-empirical, and robust tool to assess and improve semi-local density functional theory for a wide range of systems previously inaccessible to first-principles electronic structure calculations.

Bates, Jefferson E.; Furche, Filipp, E-mail: filipp.furche@uci.edu [Department of Chemistry, University of California, Irvine, 1102 Natural Sciences II, Irvine, California 92697-2025 (United States)] [Department of Chemistry, University of California, Irvine, 1102 Natural Sciences II, Irvine, California 92697-2025 (United States)

2013-11-07T23:59:59.000Z

263

Relativistic Random Phase Approximation At Finite Temperature  

SciTech Connect (OSTI)

The fully self-consistent finite temperature relativistic random phase approximation (FTRRPA) has been established in the single-nucleon basis of the temperature dependent Dirac-Hartree model (FTDH) based on effective Lagrangian with density dependent meson-nucleon couplings. Illustrative calculations in the FTRRPA framework show the evolution of multipole responses of {sup 132}Sn with temperature. With increased temperature, in both monopole and dipole strength distributions additional transitions appear in the low energy region due to the new opened particle-particle and hole-hole transition channels.

Niu, Y. F. [State Key Laboratory for Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China); Physics Department, Faculty of Science, University of Zagreb (Croatia); Paar, N.; Vretenar, D. [Physics Department, Faculty of Science, University of Zagreb (Croatia); Meng, J. [State Key Laboratory for Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China)

2009-08-26T23:59:59.000Z

264

Entangled games are hard to approximate  

E-Print Network [OSTI]

We establish the first hardness results for the problem of computing the value of one-round games played by a verifier and a team of provers who can share quantum entanglement. In particular, we show that it is NP-hard to approximate within an inverse polynomial the value of a one-round game with (i) quantum verifier and two entangled provers or (ii) classical verifier and three entangled provers. Previously it was not even known if computing the value exactly is NP-hard. We also describe a mathematical conjecture, which, if true, would imply hardness of approximation to within a constant. We start our proof by describing two ways to modify classical multi-prover games to make them resistant to entangled provers. We then show that a strategy for the modified game that uses entanglement can be ``rounded'' to one that does not. The results then follow from classical inapproximability bounds. Our work implies that, unless P=NP, the values of entangled-prover games cannot be computed by semidefinite programs that are polynomial in the size of the verifier's system, a method that has been successful for more restricted quantum games.

Julia Kempe; Hirotada Kobayashi; Keiji Matsumoto; Ben Toner; Thomas Vidick

2007-11-21T23:59:59.000Z

265

Study of Pu consumption in advanced light water reactors: Evaluation of GE advanced boiling water reactor plants - compilation of Phase 1B task reports  

SciTech Connect (OSTI)

This report contains an extensive evaluation of GE advanced boiling water reactor plants prepared for United State Department of Energy. The general areas covered in this report are: core and system performance; fuel cycle; infrastructure and deployment; and safety and environmental approval.

NONE

1993-09-15T23:59:59.000Z

266

On the mathematical treatment of the Born-Oppenheimer approximation.  

E-Print Network [OSTI]

On the mathematical treatment of the Born-Oppenheimer approximation. Thierry Jecko AGM, UMR 8088 du the main ideas used by mathematicians to show the accuracy of the Born-Oppenheimer approximation of the approximation in Chemistry. We contribute in this way to the discussion on the Born-Oppenheimer approximation

Paris-Sud XI, Université de

267

MSci Project 20142015 Dr Myrta Gruning Efficient diagonalisation of large Random-Phase Approximation  

E-Print Network [OSTI]

larger and more complex systems of interest for several applications, ranging from photovoltaics to art of non-Hermitian matrices, the Random-Phase Approx- imation (RPA) matrices. The size of those matrices matrix. However, such an approximation has been showed to breakdown for systems such as nanotubes

Paxton, Anthony T.

268

Extended-range tiltable micromirror  

DOE Patents [OSTI]

A tiltable micromirror device is disclosed in which a micromirror is suspended by a progressive linkage with an electrostatic actuator (e.g. a vertical comb actuator or a capacitive plate electrostatic actuator) being located beneath the micromirror. The progressive linkage includes a pair of torsion springs which are connected together to operate similar to a four-bar linkage with spring joints. The progressive linkage provides a non-linear spring constant which can allow the micromirror to be tilted at any angle within its range substantially free from any electrostatic instability or hysteretic behavior.

Allen, James J. (Albuquerque, NM); Wiens, Gloria J. (Newberry, FL); Bronson, Jessica R. (Gainesville, FL)

2009-05-05T23:59:59.000Z

269

Range Fuels | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentrating Solar PowerstoriesNrelPartnerType Jump to:Co JumpRETScreen Logo: Range Fuels Name:

270

APPROXIMATE DYNAMIC PROGRAMMING--II: ALGORITHMS  

E-Print Network [OSTI]

. These problems range from relatively low-dimensional applications to very high- dimensional industrial problems of uncertainty. A short list of applications, which illustrate different prob- lem classes, include the following of Go. · Controlling a Device. This might be a robot or unmanned aerial vehicle, but there is a need

Powell, Warren B.

271

Approximate Dynamic Programming -II: Warren B. Powell  

E-Print Network [OSTI]

, recently, the Chinese game of Go. · Controlling a device - This might be a robot or unmanned aerial vehicle, but there is a need for autonomous devices to manage themselves for tasks ranging from vacuuming the floor are managing blood inventories, financial portfolios or fleets of vehicles, we often have to move, transform

Powell, Warren B.

272

Summary and bibliography of safety-related events at boiling-water nuclear power plants as reported in 1980  

SciTech Connect (OSTI)

This document presents a bibliography that contains 100-word abstracts of event reports submitted to the US Nuclear Regulatory Commission concerning operational events that occurred at boiling-water-reactor nuclear power plants in 1980. The 1547 abstracts included on microfiche in this bibliography describe incidents, failures, and design or construction deficiencies that were experienced at the facilities. These abstracts are arranged alphabetically by reactor name and then chronologically for each reactor. Full-size keyword and permuted-title indexes to facilitate location of individual abstracts are provided following the text. Tables that summarize the information contained in the bibliography are also provided. The information in the tables includes a listing of the equipment items involved in the reported events and the associated number of reports for each item. Similar information is given for the various kinds of instrumentation and systems, causes of failures, deficiencies noted, and the time of occurrence (i.e., during refueling, operation, testing, or construction).

McCormack, K.E.; Gallaher, R.B.

1982-03-01T23:59:59.000Z

273

Results and phenomena observed from the DF-4 BWR (boiling water reactor) control blade-channel box test  

SciTech Connect (OSTI)

The DF-4 in-pile fuel damage experiment, one of a series of tests performed as part of the USNRC's internationally sponsored severe fuel damage (SFD) program, and carried out at Sandia National Laboratories, addressed the behavior of boiling water reactor (BWR) fuel canisters and control blades in the high temperature environment of an unrecovered loss of coolant accident. The DF-4 test is described in some detail herein and results from the experiment are presented. Significant results from prior experiments in the series are also summarized. Important findings from the DF-4 test include the low temperature melting of the stainless steel control blade caused by reaction with the B/sub 4/C, and the subsequent low temperature attack of the Zr-4 channel box by the relocating molten blade components. This early melt and relocation phenomena could significantly influence the progression of meltdown in BWRs and should be considered in SFD accident analyses. 14 refs., 9 figs.

Gauntt, R.O.; Gasser, R.D.; Fryer, C.P.; Walker, J.V.

1988-01-01T23:59:59.000Z

274

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

275

Live Fire Range Environmental Assessment  

SciTech Connect (OSTI)

The Central Training Academy (CTA) is a DOE Headquarters Organization located in Albuquerque, New Mexico, with the mission to effectively and efficiently educate and train personnel involved in the protection of vital national security interests of DOE. The CTA Live Fire Range (LFR), where most of the firearms and tactical training occurs, is a complex separate from the main campus. The purpose of the proposed action is to expand the LFR to allow more options of implementing required training. The Department of Energy has prepared this Environmental Assessment (EA) for the proposed construction and operation of an expanded Live Fire Range Facility at the Central Training Academy in Albuquerque, New Mexico. Based on the analysis in the EA, DOE has determined that the proposed action is not a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act (NEPA) of 1969. Therefore, the preparation of an environmental impact statement is not required and DOE is issuing this Finding of No Significant Impact (FONSI).

None

1993-08-01T23:59:59.000Z

276

Investigation of the physical and numerical foundations of two-fluid representation of sodium boiling with applications to LMFBR experiments  

SciTech Connect (OSTI)

This work involves the development of physical models for the constitutive relations of a two-fluid, three-dimensional sodium boiling code, THERMIT-6S. The code is equipped with a fluid conduction model, a fuel pin model, and a subassembly wall model suitable for stimulating LMFBR transient events. Mathematically rigorous derivations of time-volume averaged conservation equations are used to establish the differential equations of THERMIT-6S. These equations are then discretized in a manner identical to the original THERMIT code. A virtual mass term is incorporated in THERMIT-6S to solve the ill-posed problem. Based on a simplified flow regime, namely cocurrent annular flow, constitutive relations for two-phase flow of sodium are derived. The wall heat transfer coefficient is based on momentum-heat transfer analogy and a logarithmic law for liquid film velocity distribution. A broad literature review is given for two-phase friction factors. It is concluded that entrainment can account for some of the discrepancies in the literature. Mass and energy exchanges are modelled by generalization of the turbulent flux concept. Interfacial drag coefficients are derived for annular flows with entrainment. Code assessment is performed by simulating three experiments for low flow-high power accidents and one experiment for low flow/low power accidents in the LMFBR. While the numerical results for pre-dryout are in good agreement with the data, those for post-dryout reveal the need for improvement of the physical models. The benefits of two-dimensional non-equilibrium representation of sodium boiling are studied.

No, H.C.; Kazimi, M.S.

1983-03-01T23:59:59.000Z

277

Semiclassical approximation to supersymmetric quantum gravity  

SciTech Connect (OSTI)

We develop a semiclassical approximation scheme for the constraint equations of supersymmetric canonical quantum gravity. This is achieved by a Born-Oppenheimer type of expansion, in analogy to the case of the usual Wheeler-DeWitt equation. The formalism is only consistent if the states at each order depend on the gravitino field. We recover at consecutive orders the Hamilton-Jacobi equation, the functional Schroedinger equation, and quantum gravitational correction terms to this Schroedinger equation. In particular, the following consequences are found: (i) the Hamilton-Jacobi equation and therefore the background spacetime must involve the gravitino, (ii) a (many-fingered) local time parameter has to be present on super Riem {sigma} (the space of all possible tetrad and gravitino fields) (iii) quantum supersymmetric gravitational corrections affect the evolution of the very early Universe. The physical meaning of these equations and results, in particular, the similarities to and differences from the pure bosonic case, are discussed.

Kiefer, Claus; Lueck, Tobias; Moniz, Paulo [Institut fuer Theoretische Physik, Universitaet zu Koeln, Zuelpicher Strasse 77, 50937 Cologne (Germany); Astronomy Unit, School of Mathematical Sciences, Queen Mary College, University of London, Mile End Road, London E1 4NS (United Kingdom)

2005-08-15T23:59:59.000Z

278

Gamow peak approximation near strong resonances  

E-Print Network [OSTI]

We discuss the most effective energy range for charged particle induced reactions in a plasma environment at a given plasma temperature. The correspondence between the plasma temperature and the most effective energy should be modified from the one given by the Gamow peak energy, in the presence of a significant incident-energy dependence in the astrophysical S-factor as in the case of resonant reactions. The suggested modification of the effective energy range is important not only in thermonuclear reactions at high temperature in the stellar environment, e.g., in advanced burning stages of massive stars and in explosive stellar environment, as it has been already claimed, but also in the application of the nuclear reactions driven by ultra-intense laser pulse irradiations.

Kimura, Sachie

2013-01-01T23:59:59.000Z

279

Wide-range voltage modulation  

SciTech Connect (OSTI)

The Superconducting Super Collider`s Medium Energy Booster Abort (MEBA) kicker modulator will supply a current pulse to the abort magnets which deflect the proton beam from the MEB ring into a designated beam stop. The abort kicker will be used extensively during testing of the Low Energy Booster (LEB) and the MEB rings. When the Collider is in full operation, the MEBA kicker modulator will abort the MEB beam in the event of a malfunction during the filling process. The modulator must generate a 14-{mu}s wide pulse with a rise time of less than 1 {mu}s, including the delay and jitter times. It must also be able to deliver a current pulse to the magnet proportional to the beam energy at any time during ramp-up of the accelerator. Tracking the beam energy, which increases from 12 GeV at injection to 200 GeV at extraction, requires the modulator to operate over a wide range of voltages (4 kV to 80 kV). A vacuum spark gap and a thyratron have been chosen for test and evaluation as candidate switches for the abort modulator. Modulator design, switching time delay, jitter and pre-fire data are presented.

Rust, K.R.; Wilson, J.M.

1992-06-01T23:59:59.000Z

280

Adaptive approximation of higher order posterior statistics  

SciTech Connect (OSTI)

Filtering is an approach for incorporating observed data into time-evolving systems. Instead of a family of Dirac delta masses that is widely used in Monte Carlo methods, we here use the Wiener chaos expansion for the parametrization of the conditioned probability distribution to solve the nonlinear filtering problem. The Wiener chaos expansion is not the best method for uncertainty propagation without observations. Nevertheless, the projection of the system variables in a fixed polynomial basis spanning the probability space might be a competitive representation in the presence of relatively frequent observations because the Wiener chaos approach not only leads to an accurate and efficient prediction for short time uncertainty quantification, but it also allows to apply several data assimilation methods that can be used to yield a better approximate filtering solution. The aim of the present paper is to investigate this hypothesis. We answer in the affirmative for the (stochastic) Lorenz-63 system based on numerical simulations in which the uncertainty quantification method and the data assimilation method are adaptively selected by whether the dynamics is driven by Brownian motion and the near-Gaussianity of the measure to be updated, respectively.

Lee, Wonjung, E-mail: leew@maths.ox.ac.uk

2014-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "approximate boiling range" 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

Coulomb crystals in the harmonic lattice approximation  

E-Print Network [OSTI]

The dynamic structure factor ${\\tilde S}({\\bf k},\\omega)$ and the two-particle distribution function $g({\\bf r},t)$ of ions in a Coulomb crystal are obtained in a closed analytic form using the harmonic lattice (HL) approximation which takes into account all processes of multi-phonon excitation and absorption. The static radial two-particle distribution function $g(r)$ is calculated for classical ($T \\gtrsim \\hbar \\omega_p$, where $\\omega_p$ is the ion plasma frequency) and quantum ($T \\ll \\hbar \\omega_p$) body-centered cubic (bcc) crystals. The results for the classical crystal are in a very good agreement with extensive Monte Carlo (MC) calculations at $1.5 \\lesssim r/a \\lesssim 7$, where $a$ is the ion-sphere radius. The HL Coulomb energy is calculated for classical and quantum bcc and face-centered cubic crystals, and anharmonic corrections are discussed. The inelastic part of the HL static structure factor $S''(k)$, averaged over orientations of wave-vector {\\bf k}, is shown to contain pronounced singularities at Bragg diffraction positions. The type of the singularities is different in classical and quantum cases. The HL method can serve as a useful tool complementary to MC and other numerical methods.

D. A. Baiko; D. G. Yakovlev; H. E. De Witt; W. L. Slattery

1999-12-23T23:59:59.000Z

282

Approximate Weighted Matching On Emerging Manycore and Multithreaded Architectures  

SciTech Connect (OSTI)

Graph matching is a prototypical combinatorial problem with many applications in computer science and scientific computing, but algorithms for computing optimal matchings are challenging to parallelize. Approximate matching algorithms provide an alternate route for parallelization, and in many contexts compute near-optimal matchings for large-scale graphs. We present sharedmemory parallel implementations for computing half-approximate weighted matching on state-of-the-art multicore (Intel Nehalem and AMD Magny-Cours), manycore (Nvidia Tesla and Nvidia Fermi) and massively multithreaded (Cray XMT) platforms. We provide two implementations: the first implementation uses shared work queues, and is suited to all these platforms; the second implementation is based on dataflow principles, and exploits the architectural features of the Cray XMT. Using a carefully chosen dataset that exhibits characteristics from a wide range of real-world applications, we show scalable performance across different platforms. In particular, for one instance of the input, an R-MAT graph (RMAT-G), we show speedups of: about 32 on 48 cores of an AMD Magny-Cours; 7 on 8 cores of Intel Nehalem; 3 on Nvidia Tesla and 10 on Nvidia Fermi relative to one core of Intel Nehalem; and 60 on 128 processors of Cray XMT. We demonstrate good weak and strong scaling for graphs with up to a billion edges using up to 12, 800 threads. Given the breadth of this work, we focus on simplicity and portability of software rather than excessive fine-tuning for each platform. To the best of our knowledge, this is the first such large-scale study of the half-approximate weighted matching problem on shared-memory platforms. Driven by the critical enabling role of combinatorial algorithms such as matching in scientific computing and the emergence of informatics applications, there is a growing demand to support irregular computations on current and future computing platforms. In this context, we evaluate the capability of emerging multithreaded platforms to tolerate latency induced by irregular memory access patterns, and to support fine-grained parallelism via light-weight synchronization mechanisms. By contrasting the architectural features of these platforms against the Cray XMT, which is specifically designed to support irregular memory-intensive applications, we delineate the impact of these choices on performance.

Halappanavar, Mahantesh; Feo, John T.; Villa, Oreste; Tumeo, Antonino; Pothen, Alex

2012-11-30T23:59:59.000Z

283

On the approximations of the distribution function of fusion alpha particles  

SciTech Connect (OSTI)

The solution of the drift-kinetic equation for fusion-born alpha particles is derived in the limit of dominant parallel streaming, and it is related to the usual slowing-down distribution function. The typical approximations of the fast tail of fusion-born alpha particles are briefly compared and discussed. In particular, approximating the distribution function of fast-alpha particles with an “equivalent” Maxwellian is inaccurate to describe absorption of radio-frequency waves in the ion-cyclotron range of frequencies.

Bilato, R., E-mail: roberto.bilato@ipp.mpg.de; Brambilla, M.; Poli, E. [Max Planck Institute for Plasma Physics, EURATOM Association, Boltzmannstr. 2, 85748 Garching (Germany)

2014-10-15T23:59:59.000Z

284

Three fast computational approximation methods in hypersonic aerothermodynamics  

E-Print Network [OSTI]

Three fast computational approximation methods in hypersonic aerothermodynamics V.V. Riabov* Rivier analyzed to study nonequilibrium hypersonic viscous flows near blunt bodies. These approximations allow; Nonequilibrium hypersonic flows 1. Introduction Numerous methods [1,2] that require significant computational

Riabov, Vladimir V.

285

Approximate Linear Programming for Firstorder MDPs Scott Sanner  

E-Print Network [OSTI]

, the bounds that we derive for approximation error apply equally to all domain instantiations (i.eApproximate Linear Programming for First­order MDPs Scott Sanner University of Toronto Department

Sanner, Scott

286

Bond selective chemistry beyond the adiabatic approximation  

SciTech Connect (OSTI)

One of the most important challenges in chemistry is to develop predictive ability for the branching between energetically allowed chemical reaction pathways. Such predictive capability, coupled with a fundamental understanding of the important molecular interactions, is essential to the development and utilization of new fuels and the design of efficient combustion processes. Existing transition state and exact quantum theories successfully predict the branching between available product channels for systems in which each reaction coordinate can be adequately described by different paths along a single adiabatic potential energy surface. In particular, unimolecular dissociation following thermal, infrared multiphoton, or overtone excitation in the ground state yields a branching between energetically allowed product channels which can be successfully predicted by the application of statistical theories, i.e. the weakest bond breaks. (The predictions are particularly good for competing reactions in which when there is no saddle point along the reaction coordinates, as in simple bond fission reactions.) The predicted lack of bond selectivity results from the assumption of rapid internal vibrational energy redistribution and the implicit use of a single adiabatic Born-Oppenheimer potential energy surface for the reaction. However, the adiabatic approximation is not valid for the reaction of a wide variety of energetic materials and organic fuels; coupling between the electronic states of the reacting species play a a key role in determining the selectivity of the chemical reactions induced. The work described below investigated the central role played by coupling between electronic states in polyatomic molecules in determining the selective branching between energetically allowed fragmentation pathways in two key systems.

Butler, L.J. [Univ. of Chicago, IL (United States)

1993-12-01T23:59:59.000Z

287

Regular Type III and Type N Approximate Solutions  

E-Print Network [OSTI]

New type III and type N approximate solutions which are regular in the linear approximation are shown to exist. For that, we use complex transformations on self-dual Robinson-Trautman metrics rather then the classical approach. The regularity criterion is the boundedness and vanishing at infinity of a scalar obtained by saturating the Bel-Robinson tensor of the first approximation by a time-like vector which is constant with respect to the zeroth approximation.

Philip Downes; Paul MacAllevey; Bogdan Nita; Ivor Robinson

2001-05-18T23:59:59.000Z

288

Optimization Online - Approximation of rank function and its ...  

E-Print Network [OSTI]

Jul 10, 2011 ... Particularly, with two families of approximation functions, we ... Citation: Department of Mathematics, South China University of Technology, ...

shujun Bi

2011-07-10T23:59:59.000Z

289

On the mathematical treatment of the Born-Oppenheimer approximation.  

E-Print Network [OSTI]

On the mathematical treatment of the Born-Oppenheimer approximation. Thierry Jecko AGM, UMR 8088 du the main ideas used by mathematicians to show the accuracy of the Born-Oppenheimer approximation in this way to the discussion on the Born-Oppenheimer approximation initiated in [SW]. The paper neither

290

On the mathematical treatment of the Born-Oppenheimer approximation.  

E-Print Network [OSTI]

On the mathematical treatment of the Born-Oppenheimer approximation. Thierry Jecko AGM, UMR 8088 du the main ideas used by mathematicians to show the accuracy of the Born-Oppenheimer approximation in this way to the discussion on the Born-Oppenheimer approximation initiated in [SW1]. The paper neither

Paris-Sud XI, Université de

291

SUBTRACTING A BEST RANK-1 APPROXIMATION MAY INCREASE TENSOR RANK  

E-Print Network [OSTI]

SUBTRACTING A BEST RANK-1 APPROXIMATION MAY INCREASE TENSOR RANK Alwin Stegeman Heymans Institute, fax: +33 4 92 94 28 98, pcomon@unice.fr ABSTRACT Is has been shown that a best rank-R approximation be solved by consecutively computing and substracting best rank-1 approximations. The reason

Paris-Sud XI, Université de

292

Smoluchowski-Kramers approximation in the case of variable friction  

E-Print Network [OSTI]

We consider the small mass asymptotics (Smoluchowski-Kramers approximation) for the Langevin equation with a variable friction coefficient. The limit of the solution in the classical sense does not exist in this case. We study a modification of the Smoluchowski-Kramers approximation. Some applications of the Smoluchowski-Kramers approximation to problems with fast oscillating or discontinuous coefficients are considered.

Mark Freidlin; Wenqing Hu

2012-03-03T23:59:59.000Z

293

Testing the accuracy of radiative cooling approximations in SPH simulations  

E-Print Network [OSTI]

Hydrodynamical simulations of star formation have stimulated a need to develop fast and robust algorithms for evaluating radiative cooling. Here we undertake a critical evaluation of what is currently a popular method for prescribing cooling in SPH simulations, i.e. the polytropic cooling due originally to Stamatellos et al. This method uses the local density and potential to estimate the column density and optical depth to each particle and then uses these quantities to evaluate an approximate expression for the net radiative cooling. We evaluate the algorithm by considering both spherical and disc-like systems with analytic density and temperature structures. In spherical systems, the total cooling rate computed by the method is within around 20 for the astrophysically relevant case of opacity dominated by ice grains and is correct to within a factor of order unity for a range of opacity laws. In disc geometry, however, the method systematically under-estimates the cooling by a large factor at all heights i...

Wilkins, Daniel R

2011-01-01T23:59:59.000Z

294

Standard test method for evaluating stress-corrosion cracking of stainless alloys with different nickel content in boiling acidified sodium chloride solution  

E-Print Network [OSTI]

1.1 This test method describes a procedure for conducting stress-corrosion cracking tests in an acidified boiling sodium chloride solution. This test method is performed in 25% (by mass ) sodium chloride acidified to pH 1.5 with phosphoric acid. This test method is concerned primarily with the test solution and glassware, although a specific style of U-bend test specimen is suggested. 1.2 This test method is designed to provide better correlation with chemical process industry experience for stainless steels than the more severe boiling magnesium chloride test of Practice G36. Some stainless steels which have provided satisfactory service in many environments readily crack in Practice G36, but have not cracked during interlaboratory testing using this sodium chloride test method. 1.3 This boiling sodium chloride test method was used in an interlaboratory test program to evaluate wrought stainless steels, including duplex (ferrite-austenite) stainless and an alloy with up to about 33% nickel. It may also b...

American Society for Testing and Materials. Philadelphia

2000-01-01T23:59:59.000Z

295

Preliminary design study of small long life boiling water reactor (BWR) with tight lattice thorium nitride fuel  

SciTech Connect (OSTI)

Neutronic performance of small long-life boiling water reactors (BWR) with thorium nitride based fuel has been performed. A recent study conducted on BWR in tight lattice environments (with a lower moderator percentage) produces small power reactor which has some specifications, i.e. 10 years operation time, power density of 19.1 watt/cc and maximum excess reactivity of about 4%. This excess reactivity value is smaller than standard reactivity of conventional BWR. The use of hexagonal geometry on the fuel cell of BWR provides a substantial effect on the criticality of the reactor to obtain a longer operating time. Supported by a tight concept lattice where the volume fraction of the fuel is greater than the moderator and fuel, Thorium Nitride give good results for fuel cell design on small long life BWR. The excess reactivity of the reactor can be reduced with the addition of gadolinium as burnable poisons. Therefore the hexagonal tight lattice fuel cell design of small long life BWR that has a criticality more than 20 years of operating time has been obtained.

Trianti, Nuri, E-mail: nuri.trianti@gmail.com, E-mail: szaki@fi.itba.c.id; Su'ud, Zaki, E-mail: nuri.trianti@gmail.com, E-mail: szaki@fi.itba.c.id; Arif, Idam, E-mail: nuri.trianti@gmail.com, E-mail: szaki@fi.itba.c.id [Nuclear Physics and Biophysics Research Group, Faculty of Mathematics and Natural Science, Bandung Institute of Technology (Ganesha 10 Bandung, Indonesia) (Indonesia); Riyana, EkaSapta [Nuclear Energy Regulatory Agency (BAPETEN) (Indonesia)

2014-09-30T23:59:59.000Z

296

Load follow simulation of three-dimensional boiling water reactor core by PACS-32 parallel microprocessor system  

SciTech Connect (OSTI)

The three-dimensional boiling water reactor (BWR) core following the daily load was simulated by the use of the processor array for continuum simulation (PACS-32), a newly developed parallel microprocessor system. The PACS system consists of 32 processing units (PUs) (microprocessors) and has a multiinstruction, multidata type architecture, being optimum to the numerical simulation of the partial differential equations. The BWR core model includes the modified twogroup finite difference, coarse-mesh model for neutronics, steady-state model for thermohydraulics, criticality control by core coolant flow, and the time-dependent solution of iodine-xenon dynamics with constant flux level. The analysis of the parallel processing program revealed that the overhead is independent from the number of PUs and that the efficiency of PUs, i.e., the ratio of effective calculation over total, amounts to 75%, even up to 90% if it is limited to the core part. Simulation was made on the daily load follow for 144 h including the weekend, which took 1.3 central processing unit hours by the PACS system. The PACS system demonstrated a computation speed nearly one-tenth that of the large-scale high-speed general purpose computer, with a 25 times better cost performance ratio and showed that the system could be used as the pratical BWR core simulator with more complicated core models.

Hoshino, T.; Shirakawa, T.

1982-03-01T23:59:59.000Z

297

Summary and bibliography of safety-related events at boiling-water nuclear power plants as reported in 1979  

SciTech Connect (OSTI)

This document presents a bibliography that contains 100-word abstracts of event reports submitted to the US Nuclear Regulatory Commission concerning operational events that occurred at boiling-water-reactor nuclear power plants in 1979. The 1345 abstracts included on microfiche in this bibliography describe incidents, failures, and design or construction deficiencies that were experienced at the facilities. These abstracts are arranged alphabetically by reactor name and then chronologically for each reactor. Keyword and permuted-title indexes to facilitate location of individual abstracts are provided in full size following the text. Tables that summarize the information contained in the bibliography are also provided. The information in the tables includes a listing of the equipment items involved in the reported events and the associated number of reports for each item. Similar information is given for the various kinds of instrumentation and systems, causes of the failures, deficiencies noted, and the time of occurrence (i.e., during refueling, operation, testing, or construction). Some of the more interesting events that occurred during the year are reviewed in detail. 32 refs.

Scott, R.L.; Gallaher, R.B.

1981-06-01T23:59:59.000Z

298

Study of Pu consumption in Advanced Light Water Reactors. Evaluation of GE Advanced Boiling Water Reactor plants  

SciTech Connect (OSTI)

Timely disposal of the weapons plutonium is of paramount importance to permanently safeguarding this material. GE`s 1300 MWe Advanced Boiling Water Reactor (ABWR) has been designed to utilize fill] core loading of mixed uranium-plutonium oxide fuel. Because of its large core size, a single ABWR reactor is capable of disposing 100 metric tons of plutonium within 15 years of project inception in the spiking mode. The same amount of material could be disposed of in 25 years after the start of the project as spent fuel, again using a single reactor, while operating at 75 percent capacity factor. In either case, the design permits reuse of the stored spent fuel assemblies for electrical energy generation for the remaining life of the plant for another 40 years. Up to 40 percent of the initial plutonium can also be completely destroyed using ABWRS, without reprocessing, either by utilizing six ABWRs over 25 years or by expanding the disposition time to 60 years, the design life of the plants and using two ABWRS. More complete destruction would require the development and testing of a plutonium-base fuel with a non-fertile matrix for an ABWR or use of an Advanced Liquid Metal Reactor (ALMR). The ABWR, in addition, is fully capable of meeting the tritium target production goals with already developed target technology.

Not Available

1993-05-13T23:59:59.000Z

299

Radar range measurements in the atmosphere.  

SciTech Connect (OSTI)

The earth's atmosphere affects the velocity of propagation of microwave signals. This imparts a range error to radar range measurements that assume the typical simplistic model for propagation velocity. This range error is a function of atmospheric constituents, such as water vapor, as well as the geometry of the radar data collection, notably altitude and range. Models are presented for calculating atmospheric effects on radar range measurements, and compared against more elaborate atmospheric models.

Doerry, Armin Walter

2013-02-01T23:59:59.000Z

300

Range Condition: Key to Sustained Ranch Productivity  

E-Print Network [OSTI]

species composition is the criteria used to make this determination. Range condition is evaluated for each range site on a ranch. Range sites are areas with the potential for producing similar amounts and kinds of vegetation (for example, shallow hillside... site, deep upland site, draw site, etc.). Sites are determined by climatic, soil, topographic and vegetation features. A complete listing and description of all range sites on a ranch can be obtained from the Soil Conservation Service (SCS). Range...

McGinty, Allan; White, Larry D.

2000-04-25T23:59:59.000Z

Note: This page contains sample records for the topic "approximate boiling range" 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.


301

Short-range correlations and neutrinoless double beta decay  

E-Print Network [OSTI]

In this work we report on the effects of short-range correlations upon the matrix elements of neutrinoless double beta decay. We focus on the calculation of the matrix elements of the neutrino-mass mode of neutrinoless double beta decays of 48Ca and 76Ge. The nuclear-structure components of the calculation, that is the participant nuclear wave functions, have been calculated in the shell-model scheme for 48Ca and in the proton-neutron quasiparticle random-phase approximation (pnQRPA) scheme for 76Ge. We compare the traditional approach of using the Jastrow correlation function with the more complete scheme of the unitary correlation operator method (UCOM). Our results indicate that the Jastrow method vastly exaggerates the effects of short-range correlations on the neutrinoless double beta decay nuclear matrix elements.

M. Kortelainen; O. Civitarese; J. Suhonen; J. Toivanen

2007-01-18T23:59:59.000Z

302

On Cartesian trees and range minimum queries  

E-Print Network [OSTI]

We present new results on Cartesian trees with applications in range minimum queries and bottleneck edge queries. We introduce a cache-oblivious Cartesian tree for solving the range minimum query problem, a Cartesian tree ...

Demaine, Erik D.

303

Viking Range: Order (2014-CE-23014)  

Broader source: Energy.gov [DOE]

DOE ordered Viking Range, LLC to pay a $8,000 civil penalty after finding Viking Range had failed to certify that certain models of cooking products comply with the applicable energy conservation standards.

304

American Range: Order (2014-CE-23006)  

Broader source: Energy.gov [DOE]

DOE ordered American Range Corporation to pay a $8,000 civil penalty after finding American Range had failed to certify that certain models of cooking products comply with the applicable energy conservation standards.

305

Outcome-Space Outer Approximation Algorithm for Linear ...  

E-Print Network [OSTI]

Jul 20, 2007 ... This paper presents an outcome-space outer approximation algo- rithm for globally solving the linear multiplicative programming prob- lem.

2007-07-20T23:59:59.000Z

306

Bethe free-energy approximations for disordered quantum systems  

E-Print Network [OSTI]

Given a locally consistent set of reduced density matrices, we construct approximate density matrices which are globally consistent with the local density matrices we started from when the trial density matrix has a tree structure. We employ the cavity method of statistical physics to find the optimal density matrix representation by slowly decreasing the temperature in an annealing algorithm, or by minimizing an approximate Bethe free energy depending on the reduced density matrices and some cavity messages originated from the Bethe approximation of the entropy. We obtain the classical Bethe expression for the entropy within a naive (mean-field) approximation of the cavity messages, which is expected to work well at high temperatures. In the next order of the approximation, we obtain another expression for the Bethe entropy depending only on the diagonal elements of the reduced density matrices. In principle, we can improve the entropy approximation by considering more accurate cavity messages in the Bethe approximation of the entropy. We compare the annealing algorithm and the naive approximation of the Bethe entropy with exact and approximate numerical simulations for small and large samples of the random transverse Ising model on random regular graphs.

I. Biazzo; A. Ramezanpour

2014-07-08T23:59:59.000Z

307

approximate analytical structural: Topics by E-print Network  

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

developed method has been extended to a nonlocal equation arising in steady water wave propagation in two dimensions. We obtain analyic approximation of steady water wave...

308

E-Print Network 3.0 - approximation descriptions microscopiques...  

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

de l'approximation locale. Ce calcul est entirement... :lpmmc.grenoble.cnrs.frspip.php?article404 Description : Les polaritons de cavit sont des quasiparticules hybrides...

309

On Low Rank Matrix Approximations with Applications to Synthesis ...  

E-Print Network [OSTI]

a given matrix by a matrix of specified (low rank) in the uniform norm. ... Note that in the existing literature on low rank approximation of matrices the empha-.

2011-05-23T23:59:59.000Z

310

Finding approximately rank-one submatrices with the nuclear norm ...  

E-Print Network [OSTI]

We propose a convex optimization formulation with the nuclear norm and l1-norm to find a large approximately rank-one submatrix of a given nonnegative matrix ...

2010-11-08T23:59:59.000Z

311

Finding approximately rank-one submatrices with the nuclear norm ...  

E-Print Network [OSTI]

Nov 8, 2010 ... Abstract: We propose a convex optimization formulation with the nuclear norm and $\\ell_1$-norm to find a large approximately rank-one ...

Xuan Vinh Doan

2010-11-08T23:59:59.000Z

312

aerodynamic response approximation: Topics by E-print Network  

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

Page Topic Index 1 Managing Approximate Models in Evolutionary Aerodynamic Design Optimization Computer Technologies and Information Sciences Websites Summary: algorithm to a...

313

Better approximation guarantees for job-shop scheduling  

SciTech Connect (OSTI)

Job-shop scheduling is a classical NP-hard problem. Shmoys, Stein & Wein presented the first polynomial-time approximation algorithm for this problem that has a good (polylogarithmic) approximation guarantee. We improve the approximation guarantee of their work, and present further improvements for some important NP-hard special cases of this problem (e.g., in the preemptive case where machines can suspend work on operations and later resume). We also present NC algorithms with improved approximation guarantees for some NP-hard special cases.

Goldberg, L.A.; Paterson, M. [Univ. of Warwick, Conventry (United Kingdom); Srinivasan, A. [National Univ. of Singapore (Singapore)] [and others

1997-06-01T23:59:59.000Z

314

An Outer-Inner Approximation for separable MINLPs  

E-Print Network [OSTI]

In this paper, we propose several improvements to outer approximation for a subclass of ..... The third and last ingredient, is a procedure for finding a first feasible ...

2011-06-03T23:59:59.000Z

315

approximate block newton: Topics by E-print Network  

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

Abstract An extended product-form approximation, based on the principle of maximum entropy (ME), is characterised Ould-Khaoua, Mohamed 28 Low-lying dipole response...

316

Range Fuels Commercial-Scale Biorefinery  

Broader source: Energy.gov [DOE]

The Range Fuels commercial-scale biorefinery will use a variety of feedstocks to create cellulosic ethanol, methanol, and power.

317

A phenomenological model of thermal-hydraulics of convective boiling during the quenching of hot rod bundles  

SciTech Connect (OSTI)

After completion of the thermal-hydraulic model developed in a companion paper, the authors performed developmental assessment calculation of the model using steady-state and transient post-critical heat flux (CHF) data. This paper discusses the results of those calculations. The overall interfacial drag model predicted reasonable drag coefficients for both the nucleate boiling and the inverted annular flow (IAF) regimes. The predicted pressure drops agreed reasonably well with the measured data of two transient experiments, CCTF Run 14 and a Lehigh reflood test. The thermal-hydraulic model for post-CHF convective heat transfer predicted the rewetting velocities reasonably well for both experiments. The predicted average slope of the wall temperature traces for these tests showed reasonable agreement with the measured data, indicating that the transient-calculated precursory cooling rates agreed with measured data. The hot-patch model, in conjunction with the other thermal-hydraulic models, was capable of modeling the Winfrith post-CHF hot-patch experiments. The hot-patch model kept the wall temperatures at the specified levels in the hot-patch regions and did not allow any quench-front propagation from either the bottom or the top of the test section. The interfacial heat-transfer model tended to slightly underpredict the vapor temperatures. The maximum difference between calculated and measured vapor temperatures was 20%, with a 10% difference for the remainder of the runs considered. The wall-to-fluid heat transfer was predicted reasonably well, and the predicted wall temperatures were in reasonable agreement with measured data with a maximum relative error of less than 13%.

Unal, C.; Nelson, R.

1991-01-01T23:59:59.000Z

318

Born-Oppenheimer approximation for a harmonic molecule  

E-Print Network [OSTI]

We apply the Born-Oppenheimer approximation to a harmonic diatomic molecule with one electron. We compare the exact and approximate results not only for the internal degrees of freedom but also for the motion of the center of mass. We address the problem of identical nuclei and discuss other applications of the model and its limitations.

Francisco M. Fernandez

2008-10-13T23:59:59.000Z

319

The Born-Oppenheimer Approximation C. David Sherrill  

E-Print Network [OSTI]

The Born-Oppenheimer Approximation C. David Sherrill School of Chemistry and Biochemistry Georgia as a product of nuclear and elec- tronic terms, (r, R) = (r)(R). We thus introduce the Born-Oppenheimer that the total wavefunction is given as (r; R)(R). The Born-Oppenheimer approximation rests on the fact

Sherrill, David

320

Energy Content of Colliding Plane Waves using Approximate Noether Symmetries  

E-Print Network [OSTI]

This paper is devoted to study the energy content of colliding plane waves using approximate Noether symmetries. For this purpose, we use approximate Lie symmetry method of Lagrangian for differential equations. We formulate the first-order perturbed Lagrangian for colliding plane electromagnetic and gravitational waves. It is shown that in both cases, there does not exist

M. Sharif; Saira Waheed

2011-09-19T23:59:59.000Z

Note: This page contains sample records for the topic "approximate boiling range" 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

Parallel algorithms for approximation of distance maps on parametric surfaces  

E-Print Network [OSTI]

results demonstrate up to four orders of magnitude improvement in execution time compared to the state(n) numerical algorithm for first-order approximation of geodesic distances on geometry images, where n charts, parallel algorithms, GPU, SIMD 1. INTRODUCTION Approximation of geodesic distances on curved

Kimmel, Ron

322

Neural Network-Based Accelerators for Transcendental Function Approximation  

E-Print Network [OSTI]

Neural Network-Based Accelerators for Transcendental Function Approximation Schuyler Eldridge accelerators has the potential to sustain the his- toric energy and performance improvements of computing systems. We propose the use of NN-based accelerators to approximate mathematical functions in the GNU C

Joshi, Ajay

323

APPROXIMATE HAMILTON DECOMPOSITIONS OF ROBUSTLY EXPANDING REGULAR DIGRAPHS  

E-Print Network [OSTI]

APPROXIMATE HAMILTON DECOMPOSITIONS OF ROBUSTLY EXPANDING REGULAR DIGRAPHS DERYK OSTHUS and is a robust outexpander has an approximate decomposition into edge-disjoint Hamilton cycles, i.e. G contains a set of r -o(r) edge-disjoint Hamilton cycles. Here G is a robust outexpander if for every set S which

Osthus, Deryk

324

Absolute Approximation of Tukey Depth: Theory and Experiments  

E-Print Network [OSTI]

Absolute Approximation of Tukey Depth: Theory and Experiments Dan Chen School of Computer Science¨ur Theoretische Informatik Abstract A Monte Carlo approximation algorithm for the Tukey depth problem in high. Keywords: Tukey depth, computational geometry 1. Introduction Tukey depth is also known as location depth

Morin, Pat

325

HEREDITARY APPROXIMATION PROPERTY W. B. JOHNSON AND A. SZANKOWSKI  

E-Print Network [OSTI]

HEREDITARY APPROXIMATION PROPERTY W. B. JOHNSON AND A. SZANKOWSKI Abstract. If X is a Banach space approximation property, trace formula. Johnson was supported in part by NSF DMS-0500292, DMS-1001321, and the U.S.-Israel Binational Science Foundation. 1 #12;2 W. B. JOHNSON AND A. SZANKOWSKI (S) Is there a HAPpy space that has

Johnson, William B.

326

Vehicle Sharing System Pricing Regulation: A Fluid Approximation  

E-Print Network [OSTI]

Vehicle Sharing System Pricing Regulation: A Fluid Approximation Ariel Waserhole 1,2 Vincent Jost2 This paper gives a fluid approximation for a Vehicle Sharing System Pricing problem (VSS-P). 1. The VSS benchmark and an experimental protocol is created for the general Vehicle Sharing System optimization

327

Approximation of Harmonic Maps and Wave Maps Soren Bartels  

E-Print Network [OSTI]

Approximation of Harmonic Maps and Wave Maps S¨oren Bartels Partial differential equations to certain boundary condtions. If X = then critical points u : N are called harmonic maps into N, ·) = u0, tu(0, ·) = v0. To approximate harmonic maps or wave maps we consider a regular triangula- tion

Bartels, Soeren

328

Local Approximation of the Efficient Frontier in Robust Design  

E-Print Network [OSTI]

Local Approximation of the Efficient Frontier in Robust Design Jinhuan Zhang, Graduate Assistant as an approximation of the efficient frontier to explore alternative robust design solutions. The proposed procedure, and for efficient frontiers with both convex and nonconvex behaviors. This quadratic utility function provides

Chen, Wei

329

New approximation for free surface flow of groundwater: capillarity correction  

E-Print Network [OSTI]

capillarity correction for free surface groundwater flow as modelled by the Boussinesq equation is re; Shallow flow expansion; Simplified approximation 1. Introduction Groundwater heads in coastal aquifersNew approximation for free surface flow of groundwater: capillarity correction D.-S. Jeng a,*, B

Walter, M.Todd

330

Tonopah Test Range capabilities: technical manual  

SciTech Connect (OSTI)

This manual describes Tonopah Test Range (TTR), defines its testing capabilities, and outlines the steps necessary to schedule tests on the Range. Operated by Sandia National Laboratories, TTR is a major test facility for DOE-funded weapon programs. The Range presents an integrated system for ballistic test vehicle tracking and data acquisition. Multiple radars, optical trackers, telemetry stations, a central computer complex, and combined landline/RF communications systems assure full Range coverage for any type of test. Range operations are conducted by a department within Sandia's Field Engineering Directorate. While the overall Range functions as a complete system, it is operationally divided into the Test Measurements, Instrumentation Development, and Range Operations divisions. The primary function of TTR is to support DOE weapons test activities. Management, however, encourages other Government agencies and their contractors to schedule tests on the Range which can make effective use of its capabilities. Information concerning Range use by organizations outside of DOE is presented. Range instrumentation and support facilities are described in detail. This equipment represents the current state-of-the-art and reflects a continuing commitment by TTR management to field the most effective tracking and data acquisition system available.

Manhart, R.L.

1982-11-01T23:59:59.000Z

331

Quantitative Assessment of Range Fluctuations in Charged Particle Lung Irradiation  

SciTech Connect (OSTI)

Purpose: Water equivalent path length (WEL) variations due to respiration can change the range of a charged particle beam and result in beam overshoot to critical organs or beam undershoot to tumor. We have studied range fluctuations by analyzing four-dimensional computed tomography data and quantitatively assessing potential beam overshoot. Methods and Materials: The maximal intensity volume is calculated by combining the gross tumor volume contours at each respiratory phase in the four-dimensional computed tomography study. The first target volume calculates the maximal intensity volume for the entire respiratory cycle (internal target volume [ITV]-radiotherapy [RT]), and the second target volume is the maximal intensity volume corresponding to gated RT (gated-RT, {approx}30% phase window around exhalation). A compensator at each respiratory phase is calculated. Two 'composite' compensators for ITV-RT and gated-RT are then designed by selecting the minimal compensator depth at the respective respiratory phase. These compensators are then applied to the four-dimensional computed tomography data to estimate beam penetration. Analysis metrics include range fluctuation and overshoot volume, both as a function of gantry angle. We compared WEL fluctuations observed in treating the ITV-RT versus gated-RT in 11 lung patients. Results: The WEL fluctuations were <21.8 mm-WEL and 9.5 mm-WEL for ITV-RT and gated-RT, respectively for all patients. Gated-RT reduced the beam overshoot volume by approximately a factor of four compared with ITV-RT. Such range fluctuations can affect the efficacy of treatment and result in an excessive dose to a distal critical organ. Conclusion: Time varying range fluctuation analysis provides information useful for determining appropriate patient-specific treatment parameters in charged particle RT. This analysis can also be useful for optimizing planning and delivery.

Mori, Shinichiro [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States)], E-mail: shinshin@nirs.go.jp; Wolfgang, John; Lu, H.-M.; Schneider, Robert; Choi, Noah C.; Chen, George T.Y. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States)

2008-01-01T23:59:59.000Z

332

An improved thin film approximation to accurately determine the optical conductivity of graphene from infrared transmittance  

SciTech Connect (OSTI)

This work presents an improved thin film approximation to extract the optical conductivity from infrared transmittance in a simple yet accurate way. This approximation takes into account the incoherent reflections from the backside of the substrate. These reflections are shown to have a significant effect on the extracted optical conductivity and hence on derived parameters as carrier mobility and density. By excluding the backside reflections, the error for these parameters for typical chemical vapor deposited (CVD) graphene on a silicon substrate can be as high as 17% and 45% for the carrier mobility and density, respectively. For the mid- and near-infrared, the approximation can be simplified such that the real part of the optical conductivity is extracted without the need for a parameterization of the optical conductivity. This direct extraction is shown for Fourier transform infrared (FTIR) transmittance measurements of CVD graphene on silicon in the photon energy range of 370–7000?cm{sup ?1}. From the real part of the optical conductivity, the carrier density, mobility, and number of graphene layers are determined but also residue, originating from the graphene transfer, is detected. FTIR transmittance analyzed with the improved thin film approximation is shown to be a non-invasive, easy, and accurate measurement and analysis method for assessing the quality of graphene and can be used for other 2-D materials.

Weber, J. W.; Bol, A. A. [Department of Applied Physics, Eindhoven University of Technology, Den Dolech 2, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Sanden, M. C. M. van de [Department of Applied Physics, Eindhoven University of Technology, Den Dolech 2, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Dutch Institute for Fundamental Energy Research (DIFFER), Nieuwegein (Netherlands)

2014-07-07T23:59:59.000Z

333

Range of joint motion in college males  

E-Print Network [OSTI]

. These include the fact that there is little agreement as to the definition and limits of normal f1exibility. It was also found that the range of joint motion is highly specific and that measurement of one body joint cannot be used to predict the range... many of the problems outlined by Holland. There have been several techniques developed for measuring range of' joint motion. Adrian (1968), The American Academy of Orthopedic Surgeons (1968), Ayoub (1972), Clarke (1975), Dempster (1955), Garrett...

Houy, David Richard

1982-01-01T23:59:59.000Z

334

Range Design Criteria- June 4, 2012  

Broader source: Energy.gov [DOE]

This document contains the currently-approved firearms "Range Design Criteria" referred to on DOE O 473.3, Protection Program Operations

335

Environmental Assessment for Authorizing the Puerto Rico Electric Power Authority (PREPA) to allow Public Access to the Boiling Nuclear Superheat (BONUS) Reactor Building, Rincon, Puerto Rico  

SciTech Connect (OSTI)

The U.S. Department of Energy (DOE) proposes to consent to a proposal by the Puerto Rico Electric Power Authority (PREPA) to allow public access to the Boiling Nuclear Superheat (BONUS) reactor building located near Rincon, Puerto Rico for use as a museum. PREPA, the owner of the BONUS facility, has determined that the historical significance of this facility, as one of only two reactors of this design ever constructed in the world, warrants preservation in a museum, and that this museum would provide economic benefits to the local community through increased tourism. Therefore, PREPA is proposing development of the BONUS facility as a museum.

N /A

2003-02-24T23:59:59.000Z

336

Usefulness of bound-state approximations in reaction theory  

SciTech Connect (OSTI)

A bound-state approximation when applied to certain operators, such as the many-body resolvent operator for a two-body fragmentation channel, in many-body scattering equations, reduces such equations to equivalent two-body scattering equations which are supposed to provide a good description of the underlying physical process. In this paper we test several variants of bound-state approximations in the soluble three-boson Amado model and find that such approximations lead to weak and unacceptable kernels for the equivalent two-body scattering equations and hence to a poor description of the underlying many-body process.

Adhikari, S.K.

1981-08-01T23:59:59.000Z

337

Approximating Probability Density Functions with Mixtures of Truncated Exponentials  

E-Print Network [OSTI]

). Thus, the parameters to be estimated are a 0k , a 1k , a 2k ,a 3k , b (j) 1k ,b (j) 2k and b (j) 3k . Define ? ? (k) (x;? mk ) (abbreviated ? ? (k) (x)) as the initial MTE approximation for PDF f X (x) in interval D k .To estimate the parameters ? mk... = {a 0mk ,a 1mk ,a 2mk ,a 3mk ,b (j) 1mk ,b (j) 2mk ,b (j) 3mk } in (1), the discrete approximation to KL divergence between the standard PDF and the MTE approximation is minimized sub- ject to continuity, probability mass and non-negativity constraints...

Cobb, Barry R.; Shenoy, Prakash P.; Rumi, Rafael

2004-07-01T23:59:59.000Z

338

AdS/CFT correspondence beyond its supergravity approximation  

E-Print Network [OSTI]

We will study the AdS/CFT correspondence beyond its supergravity approximation by deforming an effective field theory on AdS by string length scale effects. We will explicitly show that the conformal dimensions of both the relevant and the irrelevant operators receive correction from these string theory effects going beyond its supergravity approximation. However, as is expected from the full string theory on AdS (not just its supergravity approximation) being dual to the $\\mathcal{N}=4$ super-Yang-Mills theory, the conformal dimension of marginal operators do not receive any such corrections.

Mir Faizal; Ahmed Farag Ali; Ali Nassar

2014-05-18T23:59:59.000Z

339

Battery Electric Vehicles: Range Optimization and Diversification for the U.S. Drivers  

SciTech Connect (OSTI)

Properly selecting the driving range is critical for accurately predicting the market acceptance and the resulting social benefits of BEVs. Analysis of transportation technology transition could be biased against battery electric vehicles (BEV) and mislead policy making, if BEVs are not represented with optimal ranges. This study proposes a coherent method to optimize the BEV driving range by minimizing the range-related cost, which is formulated as a function of range, battery cost, energy prices, charging frequency, access to backup vehicles, and the cost and refueling hassle of operating the backup vehicle. This method is implemented with a sample of 36,664 drivers, representing U.S. new car drivers, based on the 2009 National Household Travel Survey data. Key findings are: 1) Assuming the near term (2015) battery cost at $405/kWh, about 98% of the sampled drivers are predicted to prefer a range below 200 miles, and about 70% below 100 miles. The most popular 20-mile band of range is 57 to77 miles, unsurprisingly encompassing the Leaf s EPA-certified 73-mile range. With range limited to 4 or 7 discrete options, the majority are predicted to choose a range below 100 miles. 2) Found as a statistically robust rule of thumb, the BEV optimal range is approximately 0.6% of one s annual driving distance. 3) Reducing battery costs could motivate demand for larger range, but improving public charging may cause the opposite. 4) Using a single range to represent BEVs in analysis could significantly underestimate their competitiveness e.g. by $3226/vehicle if BEVs are represented with 73-mile range only or by $7404/BEV if with 150-mile range only. Range optimization and diversification into 4 or 7 range options reduce such analytical bias by 78% or 90%, respectively.

Lin, Zhenhong [ORNL] [ORNL

2012-01-01T23:59:59.000Z

340

Photometric Calibration of High Dynamic Range Cameras  

E-Print Network [OSTI]

calibration of cameras with a dynamic range of more than six orders of magnitude such as complex camera re with a total dynamic range of 8 orders of luminance magnitude. Three acquisitions: without filter, using to the measurements of 6 gray patches of GretagMacbeth ColorChecker chart under 6 different illumination conditions. 0

Durand, Frédo

Note: This page contains sample records for the topic "approximate boiling range" 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

The Joint Essential Numerical Range of operators  

E-Print Network [OSTI]

The Joint Essential Numerical Range of operators: Convexity and Related Results Chi-Kwong Li Classification 47A12, 47A13, 47A55. Keywords Joint essential numerical range, self-adjoint operator, Hilbert the joint behavior of several operators A1, . . . , Am. One may see [1, 5, 12, 14, 15, 16, 19, 23, 28, 31

Li, Chi-Kwong

342

Flux-Limited Diffusion Approximation Models of Giant Planet Formation by Disk Instability  

E-Print Network [OSTI]

Both core accretion and disk instability appear to be required as formation mechanisms in order to explain the entire range of giant planets found in extrasolar planetary systems. Disk instability is based on the formation of clumps in a marginally-gravitationally unstable protoplanetary disk. These clumps can only be expected to contract and survive to become protoplanets if they are able to lose thermal energy through a combination of convection and radiative cooling. Here we present several new three dimensional, radiative hydrodynamics models of self-gravitating protoplanetary disks, where radiative transfer is handled in the flux-limited diffusion approximation. We show that while the flux-limited models lead to higher midplane temperatures than in a diffusion approximation model without the flux-limiter, the difference in temperatures does not appear to be sufficiently high to have any significant effect on the formation of self-gravitating clumps. Self-gravitating clumps form rapidly in the models both...

Boss, Alan P

2008-01-01T23:59:59.000Z

343

Efficient Approximation of Diagonal Unitaries over the Clifford+T Basis  

E-Print Network [OSTI]

We present an algorithm for the approximate decomposition of diagonal operators, focusing specifically on decompositions over the Clifford+$T$ basis, that minimize the number of phase-rotation gates in the synthesized approximation circuit. The equivalent $T$-count of the synthesized circuit is bounded by $k \\, C_0 \\log_2(1/\\varepsilon) + E(n,k)$, where $k$ is the number of distinct phases in the diagonal $n$-qubit unitary, $\\varepsilon$ is the desired precision, $C_0$ is a quality factor of the implementation method ($1total entanglement cost (in $T$ gates). We determine an optimal decision boundary in $(k,n,\\varepsilon)$-space where our decomposition algorithm achieves lower entanglement cost than previous state-of-the-art techniques. Our method outperforms state-of-the-art techniques for a practical range of $\\varepsilon$ values and diagonal operators and can reduce the number of $T$ gates exponentially in $n$ when $k << 2^n$.

Jonathan Welch; Alex Bocharov; Krysta M. Svore

2014-12-22T23:59:59.000Z

344

Dispersed flow film boiling  

E-Print Network [OSTI]

Dispersed flow consists of small liquid droplets entrained in a flowing vapor. This flow regime can occur in cryogenic equipment, in steam generators, and during nuclear reactor loss of coolant accidents. A theoretical ...

Yoder, Graydon L.

1980-01-01T23:59:59.000Z

345

On the mathematical treatment of the Born-Oppenheimer approximation  

E-Print Network [OSTI]

Motivated by a paper by B.T. Sutcliffe and R.G. Woolley, we present the main ideas used by mathematicians to show the accuracy of the Born-Oppenheimer approximation for molecules. Based on mathematical works on this approximation for molecular bound states, in scattering theory, in resonance theory, and for short time evolution, we give an overview of some rigourous results obtained up to now. We also point out the main difficulties mathematicians are trying to overcome and speculate on further developments. The mathematical approach does not fit exactly to the common use of the approximation in Physics and Chemistry. We criticize the latter and comment on the differences, contributing in this way to the discussion on the Born-Oppenheimer approximation initiated by B.T. Sutcliffe and R.G. Woolley. The paper neither contains mathematical statements nor proofs. Instead we try to make accessible mathematically rigourous results on the subject to researchers in Quantum Chemistry or Physics.

Thierry Jecko

2014-04-24T23:59:59.000Z

346

Numerical Test of Born-Oppenheimer Approximation in Chaotic Systems  

E-Print Network [OSTI]

We study the validity of the Born-Oppenheimer approximation in chaotic dynamics. Using numerical solutions of autonomous Fermi accelerators, we show that the general adiabatic conditions can be interpreted as the narrowness of the chaotic region in phase space.

Jeong-Bo Shim; Mahir S. Hussein; Martina Hentschel

2009-08-04T23:59:59.000Z

347

The local potential approximation in the background field formalism  

E-Print Network [OSTI]

Working within the familiar local potential approximation, and concentrating on the example of a single scalar field in three dimensions, we show that the commonly used approximation method of identifying the total and background fields, leads to pathologies in the resulting fixed point structure and the associated spaces of eigenoperators. We then show how a consistent treatment of the background field through the corresponding modified shift Ward identity, can cure these pathologies, restoring universality of physical quantities with respect to the choice of dependence on the background field, even within the local potential approximation. Along the way we point out similarities to what has been previously found in the f(R) approximation in asymptotic safety for gravity.

I. Hamzaan Bridle; Juergen A. Dietz; Tim R. Morris

2014-03-20T23:59:59.000Z

348

APPROXIMATE HARTREE TYPE WAVE FUNCTIONS AND MATRIX ELEMENTS FOR...  

Office of Scientific and Technical Information (OSTI)

APPROXIMATE HARTREE TYPE WAVE FUNCTIONS AND MATRIX ELEMENTS FOR THE K AND L SHELLS OF ATOMS AND IONS Re-direct Destination: Temp Data Fields Meyerott, R.E. Temp Data Storage 3:...

349

A multiscale approximation algorithm for the cardinality constrained knapsack problem  

E-Print Network [OSTI]

I develop a multiscale approximation algorithm for the cardinality constrained knapsack problem. The algorithm consists of three steps: a rounding and reduction step where a hierarchical representation of the problem data ...

Krishnan, Bharath Kumar

2006-01-01T23:59:59.000Z

350

Generalized eikonal approximation for strong-field ionization  

E-Print Network [OSTI]

We develop the eikonal perturbation theory to describe the strong-field ionization by finite laser pulses. This approach in the first order with respect to the binding potential (the so-called generalized eikonal approximation) avoids a singularity at the potential center. Thus, in contrast to the ordinary eikonal approximation, it allows to treat rescattering phenomena in terms of quantum trajectories. We demonstrate how the first Born approximation and its domain of validity follow from eikonal perturbation theory. Using this approach, we study the coherent diffraction patterns in photoelectron energy spectra and their modifications induced by the interaction of photoelectrons with the atomic potential. Along with these first results, we discuss the prospects of using the generalized eikonal approximation to study strong-field ionization from multi-centered atomic systems and to study other strong-field phenomena.

Vélez, F Cajiao; Kami?ski, J Z

2015-01-01T23:59:59.000Z

351

Human sciences The human sciences database contains approximately 254 academic  

E-Print Network [OSTI]

Human sciences The human sciences database contains approximately 254 academic journals and statistical reports on the following subjects: (comparative literature, theology, history and geography, education, psychology, arts, languages and Library Science) Social sciences The social sciences database

352

Penumbra Maps: Approximate Soft Shadows in Real-Time  

E-Print Network [OSTI]

;Penumbra Map Assumptions · A hard shadow is a reasonable approximation for a shadow's umbra · Object silhouettes remain constant over light's surface #12;Key Insight · When using a hard shadow as the umbra, all

Wyman, Chris

353

Approximate Dynamic Programming with Affine ADDs Scott Sanner  

E-Print Network [OSTI]

Approximate Dynamic Programming with Affine ADDs Scott Sanner NICTA and ANU Canberra, Australia and Multiagent Systems (AAMAS 2010), van der Hoek, Kaminka, Lespérance, Luck and Sen (eds.), May, 10­14, 2010

Sanner, Scott

354

SPLITTING MANIFOLD APPROXIMATE FIBRATIONS J. L. BRYANT AND P. KIRBY  

E-Print Network [OSTI]

SPLITTING MANIFOLD APPROXIMATE FIBRATIONS J. L. BRYANT AND P. KIRBY Abstract. Suppose M, embeddings. Partially supported by NSF grant DMS-9626624. 1 #12; 2 J. L. BRYANT AND P. KIRBY 2. Definitions

Aluffi, Paolo

355

Approximate Associative Memristive Memory for Energy-Efficient GPUs  

E-Print Network [OSTI]

Approximate Associative Memristive Memory for Energy-Efficient GPUs Abbas Rahimi, Amirali Ghofrani at the architectural and algorithmic levels. At the hardware level, energy-efficiency techniques that employ voltage

Liebling, Michael

356

Approximation algorithms for grammar-based data compression  

E-Print Network [OSTI]

This thesis considers the smallest grammar problem: find the smallest context-free grammar that generates exactly one given string. We show that this problem is intractable, and so our objective is to find approximation ...

Lehman, Eric (Eric Allen), 1970-

2002-01-01T23:59:59.000Z

357

Regularity and approximation of systems arising in electromagnetic interrogation of  

E-Print Network [OSTI]

Regularity and approximation of systems arising in electromagnetic interrogation of dielectric describes the electromagnetic interrogation of dielectric materials. We address the well describing the electromagnetic in- terrogation of dielectric materials. Let E and H be the intensities

358

Approximate translation : media, narrative, and experience in urban design  

E-Print Network [OSTI]

Approximate translation is developed as a design process through which the place-embedded history of an urban environment can be understood, allowing for better design and intervention in that urban environment. Generally, ...

Crisman, Jonathan

2013-01-01T23:59:59.000Z

359

Approximating the Minimum Spanning Tree Weight in Sublinear Time  

E-Print Network [OSTI]

Approximating the Minimum Spanning Tree Weight in Sublinear Time Bernard Chazelle #3; Ronitt a parameter 0 minimum spanning tree- components algorithm picks O(1=#15; 2 ) vertices in the graph and then grows \\local spanning trees" whose

Trevisan, Luca

360

Adaptive Gaussian Predictive Process Approximation Surya T Tokdar  

E-Print Network [OSTI]

exploration of Gaussian process models, including Bayesian treatments. For theoreti- cal details on commonAdaptive Gaussian Predictive Process Approximation Surya T Tokdar Duke University Abstract We address the issue of knots selection for Gaussian predictive process methodology. Predictive process

West, Mike

Note: This page contains sample records for the topic "approximate boiling range" 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

Approximate dynamic programming with applications in multi-agent systems  

E-Print Network [OSTI]

This thesis presents the development and implementation of approximate dynamic programming methods used to manage multi-agent systems. The purpose of this thesis is to develop an architectural framework and theoretical ...

Valenti, Mario J. (Mario James), 1976-

2007-01-01T23:59:59.000Z

362

PLASMA Approximate Dynamic Programming finally cracks the locomotive optimization problem  

E-Print Network [OSTI]

PLASMA ­ Approximate Dynamic Programming finally cracks the locomotive optimization problem schedules and new operating policies. PLASMA is currently running at Norfolk Southern for strategic of PLASMA: Each locomotive is modeled individually, making it possible to capture both horsepower

Powell, Warren B.

363

The time-dependent Born-Oppenheimer approximation  

E-Print Network [OSTI]

We explain why the conventional argument for deriving the time-dependent Born-Oppenheimer approximation is incomplete and review recent mathematical results, which clarify the situation and at the same time provide a systematic scheme for higher order corrections. We also present a new elementary derivation of the correct second-order time-dependent Born-Oppenheimer approximation and discuss as applications the dynamics near a conical intersection of potential surfaces and reactive scattering.

Gianluca Panati; Herbert Spohn; Stefan Teufel

2007-12-28T23:59:59.000Z

364

Inverse bremsstrahlung heating rate in xenon clusters in the eikonal approximation  

SciTech Connect (OSTI)

We report inverse bremsstrahlung (IB) heating rates in the eikonal approximation (EA). The present analysis is performed using the plasma-screened Rogers and Debye potentials for Xe clusters with two different charge states (6 and 10). We compare the eikonal results with the first Born approximation (FBA) and classical-simulation (CL-sim) (Moll et al., Phys. Plasmas 19, 033303 (2012)) calculations for clusters in infrared light. Calculations have been performed for the field strength of 2.6 Multiplication-Sign 10{sup 8} V/cm. We find that compared to the FBA and CL-sim methods, the IB heating rate in the EA is less sensitive to the choice of the two potentials considered here. The present EA calculation shows that the influence of the inner structure of atomic ion on the heating rate is more prominent for the smaller ion charge (Xe{sup 6+}). In the case of low laser field approximation based on the elastic transport cross sections, it is seen that in contrast to the FBA and classical methods, the heating rate predicted by the EA does not deviate much all over the range of mean kinetic energy of electrons (20-500 eV) considered here for both the charge states of xenon (Xe{sup 6+} and Xe{sup 10+}). Furthermore, for the Rogers potential, EA is found to be in closer agreement with the classical method than the FBA. We also compare the results of the IB heating rate using the present and low-field approximation approaches to the above three methods and observe that the magnitudes of the IB heating rate calculated in the low field approximation are, in general, higher than the corresponding values predicted by the present approach for both the electron-ion potentials.

Dey, R. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, Boltzmannstr. 2, 85748 Garching (Germany); Roy, A. C. [School of Mathematical Sciences, Ramakrishna Mission Vivekananda University, Belur Math, 711202 West Bengal (India)

2013-03-15T23:59:59.000Z

365

Neutron scattering and extra short range interactions  

E-Print Network [OSTI]

The available data on neutron scattering were analyzed to constrain a hypothetical new short-range interaction. We show that these constraints are several orders of magnitude better than those usually cited in the range between 1 pm and 5 nm. This distance range occupies an intermediate space between collider searches for strongly coupled heavy bosons and searches for new weak macroscopic forces. We emphasise the reliability of the neutron constraints in so far as they provide several independent strategies. We have identified the most promising way to improve them.

V. V. Nesvizhevsky; G. Pignol; K. V. Protasov

2007-11-14T23:59:59.000Z

366

Techniques for optically compressing light intensity ranges  

DOE Patents [OSTI]

A pin hole camera assembly for use in viewing an object having a relatively large light intensity range, for example a crucible containing molten uranium in an atomic vapor laser isotope separator (AVLIS) system is disclosed herein. The assembly includes means for optically compressing the light intensity range appearing at its input sufficient to make it receivable and decipherable by a standard video camera. A number of different means for compressing the intensity range are disclosed. These include the use of photogray glass, the use of a pair of interference filters, and the utilization of a new liquid crystal notch filter in combination with an interference filter. 18 figs.

Rushford, M.C.

1989-03-28T23:59:59.000Z

367

Shorter Tours by Nicer Ears 7/5-approximation for graphic TSP,  

E-Print Network [OSTI]

case called Graphic TSP: approximation ratio 1.5 - (Gharan, Saberi, Singh [2011]) approximation ratio 1, Saberi, Singh [2011]) approximation ratio 1.461 (M¨omke, Svensson [2011]) approximation ratio 1

Vygen, Jens

368

Long Range Campus Development Plan Existing Conditions  

E-Print Network [OSTI]

design solutions and in serving members of the larger community. The Long Range Campus Development Plan environments and year-round recreation opportunities. During the summer season, daylight lasts into the evening

Maxwell, Bruce D.

369

Long range transport of acid rain precursors  

E-Print Network [OSTI]

A model of the long range transport of primary and secondary pollutants derived by Fay and Rosenzweig (1) is applied to the problem of the transport of acid rain precursors. The model describes the long term average (annual ...

Fay, James A.

1983-01-01T23:59:59.000Z

370

Systematic ranging and late warning asteroid impacts  

E-Print Network [OSTI]

We describe systematic ranging, an orbit determination technique especially suitable to assess the near-term Earth impact hazard posed by newly discovered asteroids. For these late warning cases, the time interval covered by the observations is generally short, perhaps a few hours or even less, which leads to severe degeneracies in the orbit estimation process. The systematic ranging approach gets around these degeneracies by performing a raster scan in the poorly-constrained space of topocentric range and range rate, while the plane of sky position and motion are directly tied to the recorded observations. This scan allows us to identify regions corresponding to collision solutions, as well as potential impact times and locations. From the probability distribution of the observation errors, we obtain a probability distribution in the orbital space and then estimate the probability of an Earth impact. We show how this technique is effective for a number of examples, including 2008 TC3 and 2014 AA, the only tw...

Farnocchia, D; Micheli, M

2015-01-01T23:59:59.000Z

371

Long range interactions in nanoscale science  

E-Print Network [OSTI]

Our understanding of the “long range” electrodynamic, electrostatic, and polar interactions that dominate the organization of small objects at separations beyond an interatomic bond length is reviewed. From this basic-forces ...

Rajter, Richard F.

372

Programmable near-infrared ranging system  

DOE Patents [OSTI]

A high angular resolution ranging system particularly suitable for indoor plications involving mobile robot navigation and collision avoidance uses a programmable array of light emitters that can be sequentially incremented by a microprocessor. A plurality of adjustable level threshold detectors are used in an optical receiver for detecting the threshold level of the light echoes produced when light emitted from one or more of the emitters is reflected by a target or object in the scan path of the ranging system.

Everett, Jr., Hobart R. (San Diego, CA)

1989-01-01T23:59:59.000Z

373

Variational principles with Padé approximants for tearing mode analysis  

SciTech Connect (OSTI)

Tearing modes occur in several distinct physical regimes, and it is often important to compute the inner layer response for these modes with various effects. There is a need for an approximate and efficient method of solving the inner layer equations in all these regimes. In this paper, we introduce a method of solving the inner layer equations based on using a variational principle with Padé approximants. For all the regimes considered, the main layer equations to be solved are inhomogeneous, and Padé approximants give a convenient and efficient method of satisfying the correct asymptotic behavior at the edge of the layer. Results using this variational principle—Padé approximant method in three of these regimes is presented. These regimes are the constant-? resistive-inertial (RI) regime, the constant-? viscoresistive regime, and the non-constant-? inviscid tearing regime. The last regime includes the constant-? RI regime and the inertial regime. The results show that reasonable accuracy can be obtained very efficiently with Padé approximants having a small number of parameters.

Cole, Andrew J. [Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027 (United States)] [Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027 (United States); Finn, John M. [Applied Mathematics and Plasma Physics, Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)] [Applied Mathematics and Plasma Physics, Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)

2014-03-15T23:59:59.000Z

374

Anisotropic Homogeneous Cosmologies in the Post-Newtonian Approximation  

E-Print Network [OSTI]

In this paper we explore how far the post-Newtonian theory goes in overcoming the difficulties associated with anisotropic homogeneous cosmologies in the Newtonian approximation. It will be shown that, unlike in the Newtonian case, the cosmological equations of the post-Newtonian approximation are much more in the spirit of general relativity with regard to the nine Bianchi types and issues of singularities. The situations of vanishing rotation and vanishing shear are treated separately. The homogeneous Bianchi I model is considered as an example of a rotation-free cosmology with anisotropy. It is found in the Newtonian approximation that there are arbitrary functions that need to be given for all time if the initial value problem is to be well-posed, while in the post-Newtonian case there is no such need. For the general case of a perfect fluid only the post-Newtonian theory can satisfactorily describe the effects of pressure. This is in accordance with findings in an earlier paper where the post-Newtonian approximation was applied to homogeneous cosmologies. For a shear-free anisotropic homogeneous cosmology the Newtonian theory of Heckmann and Sch\\"ucking is explored. Comparisons with its relativistic and post-Newtonian counterparts are made. In the Newtonian theory solutions exist to which there are no analogues in general relativity. The post-Newtonian approximation may provide a way out.

Tamath Rainsford

2000-07-23T23:59:59.000Z

375

Approximate semi-analytical solutions for the steady-state expansion of a contactor plasma  

E-Print Network [OSTI]

We study the steady-state expansion of a collisionless, electrostatic, quasi-neutral plasma plume into vacuum, with a fluid model. We analyze approximate semi-analytical solutions, that can be used in lieu of much more expensive numerical solutions. In particular, we focus on the earlier studies presented in Parks and Katz (1979), Korsun and Tverdokhlebova (1997), and Ashkenazy and Fruchtman (2001). By calculating the error with respect to the numerical solution, we can judge the range of validity for each solution. Moreover, we introduce a generalization of earlier models that has a wider range of applicability, in terms of plasma injection profiles. We conclude by showing a straightforward way to extend the discussed solutions to the case of a plasma plume injected with non-null azimuthal velocity.

Camporeale, E; MacDonald, E A

2015-01-01T23:59:59.000Z

376

Laser Range Finder Objective: Use a forward pointing laser range finder to  

E-Print Network [OSTI]

Laser Range Finder Objective: Use a forward pointing laser range finder to detect and avoid obstacles. Principle Investigators: Randy Beard, Tim McLain Laser Range Finder Opti-Logic RS400 Laser path, laser detects object. 2. Upon detection, insert cylindrical object into world map and plan path

Wirthlin, Michael J.

377

Non-perturbative QCD amplitudes in quenched and eikonal approximations  

SciTech Connect (OSTI)

Even though approximated, strong coupling non-perturbative QCD amplitudes remain very difficult to obtain. In this article, in eikonal and quenched approximations at least, physical insights are presented that rely on the newly-discovered property of effective locality. The present article also provides a more rigorous mathematical basis for the crude approximations used in the previous derivation of the binding potential of quarks and nucleons. Furthermore, the techniques of Random Matrix calculus along with Meijer G-functions are applied to analyze the generic structure of fermionic amplitudes in QCD. - Highlights: • We discuss the physical insight of effective locality to QCD fermionic amplitudes. • We show that an unavoidable delta function goes along with the effective locality property. • The generic structure of QCD fermion amplitudes is obtained through Random Matrix calculus.

Fried, H.M. [Physics Department, Brown University, Providence, RI 02912 (United States); Grandou, T., E-mail: Thierry.Grandou@inln.cnrs.fr [Université de Nice-Sophia Antipolis, Institut Non Linéaire de Nice, UMR 6618 CNRS 7335, 1361 routes des Lucioles, 06560 Valbonne (France); Sheu, Y.-M., E-mail: ymsheu@alumni.brown.edu [Université de Nice-Sophia Antipolis, Institut Non Linéaire de Nice, UMR 6618 CNRS 7335, 1361 routes des Lucioles, 06560 Valbonne (France)

2014-05-15T23:59:59.000Z

378

Analytical approximations for x-ray cross sections III  

SciTech Connect (OSTI)

This report updates our previous work that provided analytical approximations to cross sections for both photoelectric absorption of photons by atoms and incoherent scattering of photons by atoms. This representation is convenient for use in programmable calculators and in computer programs to evaluate these cross sections numerically. The results apply to atoms of atomic numbers between 1 and 100 and for photon energiesgreater than or equal to10 eV. The photoelectric cross sections are again approximated by four-term polynomials in reciprocal powers of the photon energy. There are now more fitting intervals, however, than were used previously. The incoherent-scattering cross sections are based on the Klein-Nishina relation, but use simpler approximate equations for efficient computer evaluation. We describe the averaging scheme for applying these atomic results to any composite material. The fitting coefficients are included in tables, and the cross sections are shown graphically. 100 graphs, 1 tab.

Biggs, F; Lighthill, R

1988-08-01T23:59:59.000Z

379

Perturbative stability of the approximate Killing field eigenvalue problem  

E-Print Network [OSTI]

An approximate Killing field may be defined on a compact, Riemannian geometry by solving an eigenvalue problem for a certain elliptic operator. This paper studies the effect of small perturbations in the Riemannian metric on the resulting vector field. It shows that small metric perturbations, as measured using a Sobolev-type supremum norm on the space of Riemannian geometries on a fixed manifold, yield small perturbations in the approximate Killing field, as measured using a Hilbert-type square integral norm. It also discusses applications to the problem of computing the spin of a generic black hole in general relativity.

Christopher Beetle; Shawn Wilder

2013-12-31T23:59:59.000Z

380

Dynamical entanglement versus symmetry and dynamics of classical approximations  

SciTech Connect (OSTI)

It is shown that dynamical entanglement between two qubits depends on the symmetry of the quantum model. On the other hand, the latter is reflected in the qualitative properties of the dynamics of a classical approximation of the quantum system. For generic separable pure initial states, the dynamical entanglement is larger if the system is less symmetric and its classical approximation is chaotic. The influence of different types of Markov environments on the established relation between the dynamical entanglement, symmetry and the classical dynamics is also studied.

Buric, Nikola [Department of Physics and Mathematics, Faculty of Pharmacy, University of Beograd, Vojvode Stepe 450, 11000 Belgrade (Serbia and Montenegro)

2006-05-15T23:59:59.000Z

Note: This page contains sample records for the topic "approximate boiling range" 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

On the approximation of crack shapes found during inservice inspection  

SciTech Connect (OSTI)

This paper addresses the characterization of axial internal flaw found during inservice inspection of a pipe. J-integral distribution for various flaw shapes is obtained using line spring finite, element method. The peak J-value and its distribution across the crack is found to be characteristic feature of each shape. The triangular shape yields peak J-value away from the center, the point of depth. The elliptic approximation results in large overestimate of J-value for unsymmetric flaws. Triangular approximation is recommended for such flaws so that further service can be obtained from the component.

Bhate, S.R.; Chawla, D.S.; Kushwaha, H.S. [Bhabha Atomic Research Centre, Bombay (India)] [and others

1997-04-01T23:59:59.000Z

382

Extended range radiation dose-rate monitor  

DOE Patents [OSTI]

An extended range dose-rate monitor is provided which utilizes the pulse pileup phenomenon that occurs in conventional counting systems to alter the dynamic response of the system to extend the dose-rate counting range. The current pulses from a solid-state detector generated by radiation events are amplified and shaped prior to applying the pulses to the input of a comparator. The comparator generates one logic pulse for each input pulse which exceeds the comparator reference threshold. These pulses are integrated and applied to a meter calibrated to indicate the measured dose-rate in response to the integrator output. A portion of the output signal from the integrator is fed back to vary the comparator reference threshold in proportion to the output count rate to extend the sensitive dynamic detection range by delaying the asymptotic approach of the integrator output toward full scale as measured by the meter.

Valentine, Kenneth H. (Knoxville, TN)

1988-01-01T23:59:59.000Z

383

Supersymmetric inversion of effective-range expansions  

E-Print Network [OSTI]

A complete and consistent inversion technique is proposed to derive an accurate interaction potential from an effective-range function for a given partial wave in the neutral case. First, the effective-range function is Taylor or Pad\\'e expanded, which allows high precision fitting of the experimental scattering phase shifts with a minimal number of parameters on a large energy range. Second, the corresponding poles of the scattering matrix are extracted in the complex wave-number plane. Third, the interaction potential is constructed with supersymmetric transformations of the radial Schr\\"odinger equation. As an illustration, the method is applied to the experimental phase shifts of the neutron-proton elastic scattering in the $^1S_0$ and $^1D_2$ channels on the $[0-350]$ MeV laboratory energy interval.

Bikashkali Midya; Jérémie Evrard; Sylvain Abramowicz; O. L. Ramírez Suárez; Jean-Marc Sparenberg

2015-01-16T23:59:59.000Z

384

Supersymmetric inversion of effective-range expansions  

E-Print Network [OSTI]

A complete and consistent inversion technique is proposed to derive an accurate interaction potential from an effective-range function for a given partial wave in the neutral case. First, the effective-range function is Taylor or Pad\\'e expanded, which allows high precision fitting of the experimental scattering phase shifts with a minimal number of parameters on a large energy range. Second, the corresponding poles of the scattering matrix are extracted in the complex wave-number plane. Third, the interaction potential is constructed with supersymmetric transformations of the radial Schr\\"odinger equation. As an illustration, the method is applied to the experimental phase shifts of the neutron-proton elastic scattering in the $^1S_0$ and $^1D_2$ channels on the $[0-350]$ MeV laboratory energy interval.

Midya, Bikashkali; Abramowicz, Sylvain; Suárez, O L Ramírez; Sparenberg, Jean-Marc

2015-01-01T23:59:59.000Z

385

Flux-Limited Diffusion Approximation Models of Giant Planet Formation by Disk Instability  

E-Print Network [OSTI]

Both core accretion and disk instability appear to be required as formation mechanisms in order to explain the entire range of giant planets found in extrasolar planetary systems. Disk instability is based on the formation of clumps in a marginally-gravitationally unstable protoplanetary disk. These clumps can only be expected to contract and survive to become protoplanets if they are able to lose thermal energy through a combination of convection and radiative cooling. Here we present several new three dimensional, radiative hydrodynamics models of self-gravitating protoplanetary disks, where radiative transfer is handled in the flux-limited diffusion approximation. We show that while the flux-limited models lead to higher midplane temperatures than in a diffusion approximation model without the flux-limiter, the difference in temperatures does not appear to be sufficiently high to have any significant effect on the formation of self-gravitating clumps. Self-gravitating clumps form rapidly in the models both with and without the flux-limiter. These models suggest that the reason for the different outcomes of numerical models of disk instability by different groups cannot be attributed solely to the handling of radiative transfer, but rather appears to be caused by a range of numerical effects and assumptions. Given the observational imperative to have disk instability form at least some extrasolar planets, these models imply that disk instability remains as a viable giant planet formation mechanism.

Alan P. Boss

2008-01-28T23:59:59.000Z

386

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

387

Exchange-correlation energy from pairing matrix fluctuation and the particle-particle random phase approximation  

SciTech Connect (OSTI)

Despite their unmatched success for many applications, commonly used local, semi-local, and hybrid density functionals still face challenges when it comes to describing long-range interactions, static correlation, and electron delocalization. Density functionals of both the occupied and virtual orbitals are able to address these problems. The particle-hole (ph-) Random Phase Approximation (RPA), a functional of occupied and virtual orbitals, has recently known a revival within the density functional theory community. Following up on an idea introduced in our recent communication [H. van Aggelen, Y. Yang, and W. Yang, Phys. Rev. A 88, 030501 (2013)], we formulate more general adiabatic connections for the correlation energy in terms of pairing matrix fluctuations described by the particle-particle (pp-) propagator. With numerical examples of the pp-RPA, the lowest-order approximation to the pp-propagator, we illustrate the potential of density functional approximations based on pairing matrix fluctuations. The pp-RPA is size-extensive, self-interaction free, fully anti-symmetric, describes the strong static correlation limit in H{sub 2}, and eliminates delocalization errors in H{sub 2}{sup +} and other single-bond systems. It gives surprisingly good non-bonded interaction energies – competitive with the ph-RPA – with the correct R{sup ?6} asymptotic decay as a function of the separation R, which we argue is mainly attributable to its correct second-order energy term. While the pp-RPA tends to underestimate absolute correlation energies, it gives good relative energies: much better atomization energies than the ph-RPA, as it has no tendency to underbind, and reaction energies of similar quality. The adiabatic connection in terms of pairing matrix fluctuation paves the way for promising new density functional approximations.

Aggelen, Helen van [Department of Inorganic and Physical Chemistry, Ghent University, Ghent (Belgium) [Department of Inorganic and Physical Chemistry, Ghent University, Ghent (Belgium); Department of Chemistry, Duke University, Durham, North Carolina 27708 (United States); Yang, Yang [Department of Chemistry, Duke University, Durham, North Carolina 27708 (United States)] [Department of Chemistry, Duke University, Durham, North Carolina 27708 (United States); Yang, Weitao [Department of Chemistry and Department of Physics, Duke University, Durham, North Carolina 27708 (United States)] [Department of Chemistry and Department of Physics, Duke University, Durham, North Carolina 27708 (United States)

2014-05-14T23:59:59.000Z

388

Combining Conjugate Direction Methods with Stochastic Approximation of Gradients  

E-Print Network [OSTI]

Combining Conjugate Direction Methods with Stochastic Approximation of Gradients #3; Nicol N-8092 Zurich, Switzerland http://www.icos.ethz.ch/ Abstract The method of conjugate directions provides from conjugate gra- dient in the stochastic (online) setting, us- ing fast Hessian-gradient products

Schraudolph, Nicol N.

389

Combining Conjugate Direction Methods with Stochastic Approximation of Gradients  

E-Print Network [OSTI]

Combining Conjugate Direction Methods with Stochastic Approximation of Gradients Nicol N-8092 Z¨urich, Switzerland http://www.icos.ethz.ch/ Abstract The method of conjugate directions provides conjugate gra- dient in the stochastic (online) setting, us- ing fast Hessian-gradient products to set up

Schraudolph, Nicol N.

390

APPROXIMATE INVERSE PRECONDITIONING FOR THE CONJUGATE GRADIENT METHOD  

E-Print Network [OSTI]

APPROXIMATE INVERSE PRECONDITIONING FOR THE CONJUGATE GRADIENT METHOD ON A VECTOR COMPUTER Michele definite matrix, by the preconditioned conjugate gradient method (PCG) (see, e.g., [4]). It is well of the conjugate gradient method reduces to computing a matrix­ vector product with G, an operation which offers

Tùma, Miroslav

391

On the mathematical treatment of the Born-Oppenheimer approximation  

SciTech Connect (OSTI)

Motivated by the paper by Sutcliffe and Woolley [“On the quantum theory of molecules,” J. Chem. Phys. 137, 22A544 (2012)], we present the main ideas used by mathematicians to show the accuracy of the Born-Oppenheimer approximation for molecules. Based on mathematical works on this approximation for molecular bound states, in scattering theory, in resonance theory, and for short time evolution, we give an overview of some rigorous results obtained up to now. We also point out the main difficulties mathematicians are trying to overcome and speculate on further developments. The mathematical approach does not fit exactly to the common use of the approximation in Physics and Chemistry. We criticize the latter and comment on the differences, contributing in this way to the discussion on the Born-Oppenheimer approximation initiated by Sutcliffe and Woolley. The paper neither contains mathematical statements nor proofs. Instead, we try to make accessible mathematically rigourous results on the subject to researchers in Quantum Chemistry or Physics.

Jecko, Thierry, E-mail: thierry.jecko@u-cergy.fr [AGM, UMR 8088 du CNRS, Université de Cergy-Pontoise, Département de mathématiques, site de Saint Martin, 2 avenue Adolphe Chauvin, F-95000 Pontoise (France)] [AGM, UMR 8088 du CNRS, Université de Cergy-Pontoise, Département de mathématiques, site de Saint Martin, 2 avenue Adolphe Chauvin, F-95000 Pontoise (France)

2014-05-15T23:59:59.000Z

392

Decoupling electrons and nuclei without the Born-Oppenheimer approximation  

E-Print Network [OSTI]

Decoupling electrons and nuclei without the Born-Oppenheimer approximation Patrick Cassam. The EN-GMFCI is a new paradigm for quantum chemistry that bypasses the tradi- tional Born-Oppenheimer (BO;1 Introduction The Born-Oppenheimer (BO) potential energy surface (PES) is one of the main paradigm of quantum

Paris-Sud XI, Université de

393

Preprint UC Davis Math 199930 A continuum approximation for the  

E-Print Network [OSTI]

Preprint UC Davis Math 1999­30 A continuum approximation for the excitations of the (1; 1 and Shannon Starr Department of Mathematics University of California, Davis Davis, CA 95616­8633, USA bolina, with an appropriate scaling, the energy of low­ lying excitations of the (1; 1; : : : ; 1) interface in the d

394

HEREDITARY APPROXIMATION PROPERTY W. B. JOHNSON AND A. SZANKOWSKI  

E-Print Network [OSTI]

HEREDITARY APPROXIMATION PROPERTY W. B. JOHNSON AND A. SZANKOWSKI Abstract. If X is a Banach space, trace formula. Johnson was supported in part by NSF DMS-0500292, DMS-1001321, and the U.S.-Israel Binational Science Foundation. 1 #12;2 W. B. JOHNSON AND A. SZANKOWSKI subsymmetric basis unless

Johnson, William B.

395

Approximate hedging problem with transaction costs in stochastic volatility markets  

E-Print Network [OSTI]

Approximate hedging problem with transaction costs in stochastic volatility markets Thai Huu Nguyen stochastic volatility markets with transaction costs using a new form for enlarged volatility in Leland between the present setting and high frequency markets with transaction costs. Possibilities to improve

Paris-Sud XI, Université de

396

Approximate Minimum-Energy Multicasting in Wireless Ad Hoc Networks  

E-Print Network [OSTI]

and a set of destination nodes, the problem is to build a minimum-energy multicast tree for the requestApproximate Minimum-Energy Multicasting in Wireless Ad Hoc Networks Weifa Liang, Senior Member, IEEE Abstract--A wireless ad hoc network consists of mobile nodes that are equipped with energy

Liang, Weifa

397

Approximate Solutions and Performance Bounds for the Sensor Placement Problem  

E-Print Network [OSTI]

to place environmental sensors for an area where there are large amounts of distributed solar PV and whereApproximate Solutions and Performance Bounds for the Sensor Placement Problem Muhammad Uddin@cc.tuat.ac.jp Abstract--This paper considers the placement of m sensors at n > m possible locations. Given noisy

Kavcic, Aleksandar

398

Approximation schemes for covering and scheduling on related machines  

E-Print Network [OSTI]

Approximation schemes for covering and scheduling on related machines Yossi Azar1 ,Leah Epstein2 1 Abstract. We consider the problem of assigning a set of jobs to m par- allel related machines so as to maximize the minimum load over the machines. This situation corresponds to a case that a system which con

Azar, Yossi

399

Approximation schemes for covering and scheduling on related machines  

E-Print Network [OSTI]

Approximation schemes for covering and scheduling on related machines Yossi Azar 1 ,Leah Epstein 2­Aviv University. y Abstract. We consider the problem of assigning a set of jobs to m par­ allel related machines so as to maximize the minimum load over the machines. This situation corresponds to a case

Epstein, Leah

400

Di usion Approximation of Radiative Transfer Equations in a Channel  

E-Print Network [OSTI]

direction. 1 #12; 1 Introduction Radiative transport equations were #12;rst used to describe the propagationDi#11;usion Approximation of Radiative Transfer Equations in a Channel Guillaume Bal Department by a di#11;usion equation. However, the thickness of the crust is of the order of the transport mean free

Bal, Guillaume

Note: This page contains sample records for the topic "approximate boiling range" 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

Numerical study on the validity of the diffusion approximation  

E-Print Network [OSTI]

of photons can be accurately modeled by the radiative transport equation (RTE).9,10 Because and the radiative transport as implemented by Monte Carlo simulation in the cases of point and ball sources. Our of the difficulties in handling the RTE directly, the diffusion approximation to the transport equation has been

Virginia Tech

402

Gluon Condensate in Pion Superfluid beyond Mean Field Approximation  

E-Print Network [OSTI]

We study gluon condensate in a pion superfluid, through calculating the equation of state of the system in the Nambu-Jona-Lasinio model. While in mean field approximation the growing pion condensate leads to an increasing gluon condensate, meson fluctuations reduce the gluon condensate and the broken scalar symmetry can be smoothly restored at finite isospin density.

Yin Jiang; Pengfei Zhuang

2011-03-04T23:59:59.000Z

403

L^p Bernstein Inequalities and Radial Basis Function Approximation  

E-Print Network [OSTI]

inequalities are a recent development in the theory of RBF approximation, and on Rd, only L2 results are known for RBFs with algebraically decaying Fourier transforms (e.g. the Sobolev splines and thin-plate splines). We will therefore extend what is known...

Ward, John P.

2012-10-19T23:59:59.000Z

404

Managing Approximate Models in Evolutionary Aerodynamic Design Optimization  

E-Print Network [OSTI]

Managing Approximate Models in Evolutionary Aerodynamic Design Optimization Yaochu Jin yaochu jin­ mization problems that are discontinuous, multi­modal and multi­objective [1, 2]. Aerodynamic structural to high complexity of the aerodynamic analysis and large number of evaluations needed in the evolutionary

Coello, Carlos A. Coello

405

Aqua: A Fast Decision Support System Using Approximate Query Answers  

E-Print Network [OSTI]

commercial relational DBMS. Aqua precomputes synopses (special sta- tistical summaries) of the original data and stores them in the DBMS. It provides approximate an- swers (with quality guarantees) by rewriting on top of any SQL- compliant DBMS managing a data warehouse. Aqua pre- computes statistical summaries

Gibbons, Phillip B.

406

Exact and Approximate Sampling by Systematic Stochastic Search  

E-Print Network [OSTI]

Exact and Approximate Sampling by Systematic Stochastic Search Vikash Mansinghka MIT BCS & CSAIL exact samples over high-dimensional spaces from exact sam- ples over lower-dimensional subspaces. Our do this by generalizing ideas from classic AI search to the stochastic setting. Just as systematic

Tenenbaum, Josh

407

Self-similar and charged spheres in the diffusion approximation  

E-Print Network [OSTI]

We study spherical, charged and self--similar distributions of matter in the diffusion approximation. We propose a simple, dynamic but physically meaningful solution. For such a solution we obtain a model in which the distribution becomes static and changes to dust. The collapse is halted with damped mass oscillations about the absolute value of the total charge.

Barreto, W

1999-01-01T23:59:59.000Z

408

Fractal Inverse Problem: Approximation Formulation and Differential Methods  

E-Print Network [OSTI]

Fractal Inverse Problem: Approximation Formulation and Differential Methods ´Eric Gu´erin1 Introduction 1.1 Fractal Inverse Problem The fractal inverse problem is an important research area with a great number of potential application fields. It consists in finding a fractal model or code that generates

Guérin, Eric

409

Approximating the Minimum Spanning Tree Weight in Sublinear Time  

E-Print Network [OSTI]

Approximating the Minimum Spanning Tree Weight in Sublinear Time #3; Bernard Chazelle y Ronitt a parameter 0 minimum span- ning tree in the graph and then grows \\local spanning trees" whose sizes are speci#12;ed by a stochastic process. From

Goldwasser, Shafi

410

Calculating reactor transfer functions by Pade approximation via Lanczos algorithm  

E-Print Network [OSTI]

Calculating reactor transfer functions by PadeÃ? approximation via Lanczos algorithm Zhifeng Kuang a function of a reactor, i.e. the neutron noise induced by a localised perturbation is calculated in one, *,1 , Imre PaÃ? zsit a , Axel Ruhe b a Department of Reactor Physics, Chalmers University of Technology

Pázsit, Imre

411

On Approximating the Translational Velocity of Vortex Rings  

E-Print Network [OSTI]

from this configuration and the system scaling. Here, the accuracy of this approximation is presented orifice in a flat plate contain a converging radial component of velocity. For both configurations. By this definition, the piston velocity is the average jet velocity passing through the orifice independent

Mohseni, Kamran

412

MARKOV CHAIN APPROXIMATIONS FOR TRANSITION DENSITIES OF LEVY PROCESSES  

E-Print Network [OSTI]

MARKOV CHAIN APPROXIMATIONS FOR TRANSITION DENSITIES OF L´EVY PROCESSES ALEKSANDAR MIJATOVI for the existence of transition densities of X, we establish sharp convergence rates of the normalised probability class with applications in diverse areas such as mathematical finance, risk management, insurance

413

Gerla Giangiacomo Fuzzy logic. Mathematical tools for approximate reasoning. (English)  

E-Print Network [OSTI]

the author's approach to fuzzy control. Based upon a certain version of fuzzified logical programming, viz. Herbrand models for fuzzy logics, the author interprets lists of fuzzy control rules by fuzzy logicGerla Giangiacomo Fuzzy logic. Mathematical tools for approximate reasoning. (English) [B] Trends

Gerla, Giangiacomo

414

LIMIT THEOREMS AND APPROXIMATIONS WITH APPLICATIONS TO INSURANCE RISK AND  

E-Print Network [OSTI]

LIMIT THEOREMS AND APPROXIMATIONS WITH APPLICATIONS TO INSURANCE RISK AND QUEUEING THEORY of philosophy Jose H. Blanchet August 2004 #12;c° Copyright by Jose H. Blanchet 2004 All Rights Reserved ii #12 and quality as a dissertation for the degree of Doctor of Philosophy. Peter W. Glynn (Principal Adviser) I

Blanchet, Jose H.

415

Improved Approximations for Max Set Splitting and Max NAE SAT  

E-Print Network [OSTI]

Improved Approximations for Max Set Splitting and Max NAE SAT #3; Jiawei Zhang and Yinyu Ye y Nanjing, 210093, P.R.China August 16, 2000, Revised January 22, 2001. #3; This research was supported Fudan University, Shanghai, R.R.China. z This work was done while the author was visiting Computational

Ye, Yinyu

416

Compact range for variable-zone measurements  

DOE Patents [OSTI]

A compact range for testing antennas or radar targets includes a source for directing energy along a feedline toward a parabolic reflector. The reflected wave is a spherical wave with a radius dependent on the distance of the source from the focal point of the reflector.

Burnside, Walter D. (Columbus, OH); Rudduck, Roger C. (Columbus, OH); Yu, Jiunn S. (Albuquerque, NM)

1988-01-01T23:59:59.000Z

417

Range Creek Calibrated Dates Beta-202190  

E-Print Network [OSTI]

Range Creek Calibrated Dates 0 200 400 600 800 1000 1200 1400 Beta-202190 Beta-175753 Beta-175755 Beta-235067 Beta-202189 Beta-214831 Beta-202188 Beta-202191 Beta-203630 Beta-214832 Beta-175754 Beta a Carbon-14 calibrated date (95% CI) between 1000 and 1200 C.E. (Figure 5: Beta-235067). The calibrated

Provancher, William

418

Electrical Engineering Technology (EET) LONG RANGE SCHEDULE  

E-Print Network [OSTI]

and Machinery C T C T EET 365W Electrical Power & Machinery Laboratory C C, V V C C, V V EET 370T Energy=Virtual Laboratory, W=Web based This schedule is tentative. All Course offerings are subject to minimum enrollmentElectrical Engineering Technology (EET) LONG RANGE SCHEDULE Course Number and Name Fall 2010 Spr

419

6, 1018310216, 2006 Long-range transport  

E-Print Network [OSTI]

ACPD 6, 10183­10216, 2006 Long-range transport of Asian dust and air pollutants to Taiwan C.-Y. Lin and air pollutants to Taiwan: observed evidence and model simulation C.-Y. Lin 1 , Z. Wang 2 , W.-N. Chen and air pollutants to Taiwan C.-Y. Lin et al. Title Page Abstract Introduction Conclusions References

Boyer, Edmond

420

Gravitomagnetism and the Earth-Mercury range  

E-Print Network [OSTI]

We numerically work out the impact of the general relativistic Lense-Thirring effect on the Earth-Mercury range caused by the gravitomagnetic field of the rotating Sun. The peak-to peak nominal amplitude of the resulting time-varying signal amounts to 1.75 10^1 m over a temporal interval 2 yr. Future interplanetary laser ranging facilities should reach a cm-level in ranging to Mercury over comparable timescales; for example, the BepiColombo mission, to be launched in 2014, should reach a 4.5 - 10 cm level over 1 - 8 yr. We looked also at other Newtonian (solar quadrupole mass moment, ring of the minor asteroids, Ceres, Pallas, Vesta, Trans-Neptunian Objects) and post-Newtonian (gravitoelectric Schwarzschild solar field) dynamical effects on the Earth-Mercury range. They act as sources of systematic errors for the Lense-Thirring signal which, in turn, if not properly modeled, may bias the recovery of some key parameters of such other dynamical features of motion. Their nominal peak-to-peak amplitudes are as large as 4 10^5 m (Schwarzschild), 3 10^2 m (Sun's quadrupole), 8 10^1 m (Ceres, Pallas, Vesta), 4 m (ring of minor asteroids), 8 10^-1 m (Trans-Neptunian Objects). Their temporal patterns are different with respect to that of the gravitomagnetic signal.

Lorenzo Iorio

2011-08-29T23:59:59.000Z

Note: This page contains sample records for the topic "approximate boiling range" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

COLORADO FRONT RANGE SEISMICITY AND SEISMIC HAZARD  

E-Print Network [OSTI]

COLORADO FRONT RANGE SEISMICITY AND SEISMIC HAZARD Anne F. Sheehan University of Colorado at Boulder, 2200 Colorado Avenue, Boulder, CO 80309 John D. Godchaux Trinity University, San Antonio, TX Noah Hughes University of Colorado at Boulder, 2200 Colorado Avenue, Boulder, CO 80309 Key Terms: earthquake

Sheehan, Anne F.

422

Analytical and Experimental Study of The Effects of Non-Condensable in a Passive Condenser System for The Advanced Boiling Water Reactor  

SciTech Connect (OSTI)

The main goal of the project is to study analytically and experimentally condensation heat transfer for the passive condenser system relevant to the safety of next generation nuclear reactor such as Simplified Boiling Water Reactor (BWR). The objectives of this three-year research project are to: (1) obtain experimental data on the phenomenon of condensation of steam in a vertical tube in the presence of non-condensable for flow conditions of PCCS, (2) develop a analytic model for the condensation phenomena in the presence of non-condensable gas for the vertical tube, and (3) assess the RELAP5 computer code against the experimental data. The project involves experiment, theoretical modeling and a thermal-hydraulic code assessment. It involves graduate and undergraduate students' participation providing them with exposure and training in advanced reactor concepts and safety systems

Shripad T. Revankar; Seungmin Oh

2003-09-30T23:59:59.000Z

423

Long-range Rydberg-Rydberg interactions in calcium, strontium and ytterbium  

E-Print Network [OSTI]

Long-range dipole-dipole and quadrupole-quadrupole interactions between pairs of Rydberg atoms are calculated perturbatively for calcium, strontium and ytterbium within the Coulomb approximation. Quantum defects, obtained by fitting existing laser spectroscopic data, are provided for all $S$, $P$, $D$ and $F$ series of strontium and for the $^3P_2$ series of calcium. The results show qualitative differences with the alkali metal atoms, including isotropically attractive interactions of the strontium $^1S_0$ states and a greater rarity of F\\"orster resonances. Only two such resonances are identified, both in triplet series of strontium. The angular dependence of the long range interaction is briefly discussed.

Vaillant, C L; Potvliege, R M

2012-01-01T23:59:59.000Z

424

Long-range Rydberg-Rydberg interactions in calcium, strontium and ytterbium  

E-Print Network [OSTI]

Long-range dipole-dipole and quadrupole-quadrupole interactions between pairs of Rydberg atoms are calculated perturbatively for calcium, strontium and ytterbium within the Coulomb approximation. Quantum defects, obtained by fitting existing laser spectroscopic data, are provided for all $S$, $P$, $D$ and $F$ series of strontium and for the $^3P_2$ series of calcium. The results show qualitative differences with the alkali metal atoms, including isotropically attractive interactions of the strontium $^1S_0$ states and a greater rarity of F\\"orster resonances. Only two such resonances are identified, both in triplet series of strontium. The angular dependence of the long range interaction is briefly discussed.

C. L. Vaillant; M. P. A. Jones; R. M. Potvliege

2012-03-16T23:59:59.000Z

425

Short-Range Nucleon-Nucleon Correlations  

SciTech Connect (OSTI)

Valence-shell nucleon knock-out experiments, such as 12C(e,e'p)11B, measure less strength then is predicted by independent particle shell model calculations. The theoretical solution to this problem is to include the correlations between the nucleons in the nucleus in the calculations. Motivated by these results, many electron scattering experiments have tried to directly observe these correlations in order to gain new insight into the short-range part of the nucleon-nucleon potential. Unfortunately, many competing mechanisms can cause the same observable final-state as an initial-state correlation, making truly isolating the signal extremely challenging. This paper reviews the recent experimental evidence for short-range correlations, as well as explores the possibility that such correlations are responsible for the EMC effect in the 0.3 < xB < 0.7 deep inelastic scattering ratios.

Douglas Higinbotham

2011-10-01T23:59:59.000Z

426

Short-Range Nucleon-Nucleon Correlations  

SciTech Connect (OSTI)

Valence-shell nucleon knock-out experiments, such as {sup 12}C(e,e'p){sup 11}B, measure less strength then is predicted by independent particle shell model calculations. The theoretical solution to this problem is to include the correlations between the nucleons in the nucleus in the calculations. Motivated by these results, many electron scattering experiments have tried to isolate the signal from these correlations in order to gain new insight into the short-range part of the nucleon-nucleon potential. Unfortunately, many competing mechanisms can cause the same observable final-state as an initial-state correlation, making truly isolating the signal extremely challenging. This paper reviews the recent experimental evidence for short-range correlations, as well as explores the possibility that such correlations are responsible for the EMC effect in the 0.3

Higinbotham, Douglas W. [Thomas Jefferson National Accelerator Facility, Newport News, VA 23601 (United States)

2011-10-24T23:59:59.000Z

427

Wide range radioactive gas concentration detector  

DOE Patents [OSTI]

A wide range radioactive gas concentration detector and monitor which is capable of measuring radioactive gas concentrations over a range of eight orders of magnitude. The device of the present invention is designed to have an ionization chamber which is sufficiently small to give a fast response time for measuring radioactive gases but sufficiently large to provide accurate readings at low concentration levels. Closely spaced parallel plate grids provide a uniform electric field in the active region to improve the accuracy of measurements and reduce ion migration time so as to virtually eliminate errors due to ion recombination. The parallel plate grids are fabricated with a minimal surface area to reduce the effects of contamination resulting from absorption of contaminating materials on the surface of the grids. Additionally, the ionization chamber wall is spaced a sufficient distance from the active region of the ionization chamber to minimize contamination effects.

Anderson, David F. (Los Alamos, NM)

1984-01-01T23:59:59.000Z

428

Intermediate Range Order and Transport Processes  

E-Print Network [OSTI]

Simulation Study February 7, 2005 Patrick Pfleiderer ICP, University of Stuttgart in Collaboration: 2 2 21 ),...,,( dt d mV i iNii r rrrF =-= t m ttt ttt t m t ttttt i ii ii i i iii 2 )()( )()( 2-range and responsible for covalent character · obtained from ab initio calculations · time step: 1.6fs 6 2 r C eA r eqq

Harting, Jens

429

Causality and the effective range expansion  

E-Print Network [OSTI]

We derive the generalization of Wigner's causality bounds and Bethe's integral formula for the effective range parameter to arbitrary dimension and arbitrary angular momentum. We also discuss the impact of these constraints on the separation of low- and high-momentum scales and universality in low-energy scattering. Some of our results were summarized earlier in a letter publication. In this work, we present full derivations and several detailed examples.

H. -W. Hammer; Dean Lee

2010-07-26T23:59:59.000Z

430

Rangely, Colorado: Energy Resources | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia:FAQ < RAPID Jump to: navigation, search RAPIDColoradosource HistoryRaftRamsey,Rangely, Colorado: Energy

431

Inertial range turbulence in kinetic plasmas  

E-Print Network [OSTI]

The transfer of turbulent energy through an inertial range from the driving scale to dissipative scales in a kinetic plasma followed by the conversion of this energy into heat is a fundamental plasma physics process. A theoretical foundation for the study of this process is constructed, but the details of the kinetic cascade are not well understood. Several important properties are identified: (a) the conservation of a generalized energy by the cascade; (b) the need for collisions to increase entropy and realize irreversible plasma heating; and (c) the key role played by the entropy cascade--a dual cascade of energy to small scales in both physical and velocity space--to convert ultimately the turbulent energy into heat. A strategy for nonlinear numerical simulations of kinetic turbulence is outlined. Initial numerical results are consistent with the operation of the entropy cascade. Inertial range turbulence arises in a broad range of space and astrophysical plasmas and may play an important role in the thermalization of fusion energy in burning plasmas.

G. G. Howes

2007-11-27T23:59:59.000Z

432

Exploring approximations to the GW self-energy ionic gradients  

E-Print Network [OSTI]

The accuracy of the many-body perturbation theory GW formalism to calculate electron-phonon coupling matrix elements has been recently demonstrated in the case of a few important systems. However, the related computational costs are high and thus represent strong limitations to its widespread application. In the present study, we explore two less demanding alternatives for the calculation of electron-phonon coupling matrix elements on the many-body perturbation theory level. Namely, we test the accuracy of the static Coulomb-hole plus screened-exchange (COHSEX) approximation and further of the constant screening approach, where variations of the screened Coulomb potential W upon small changes of the atomic positions along the vibrational eigenmodes are neglected. We find this latter approximation to be the most reliable, whereas the static COHSEX ansatz leads to substantial errors. Our conclusions are validated in a few paradigmatic cases: diamond, graphene and the C60 fullerene. These findings open the way f...

Faber, C; Attaccalite, C; Cannuccia, E; Duchemin, I; Deutsch, T; Blase, X

2015-01-01T23:59:59.000Z

433

Product-state Approximations to Quantum Ground States  

E-Print Network [OSTI]

The local Hamiltonian problem consists of estimating the ground-state energy (given by the minimum eigenvalue) of a local quantum Hamiltonian. First, we show the existence of a good product-state approximation for the ground-state energy of 2-local Hamiltonians with one or more of the following properties: (1) high degree, (2) small expansion, or (3) a ground state with sublinear entanglement with respect to some partition into small pieces. The approximation based on degree is a surprising difference between quantum Hamiltonians and classical CSPs (constraint satisfaction problems), since in the classical setting, higher degree is usually associated with harder CSPs. The approximation based on low entanglement, in turn, was previously known only in the regime where the entanglement was close to zero. Since the existence of a low-energy product state can be checked in NP, the result implies that any Hamiltonian used for a quantum PCP theorem should have: (1) constant degree, (2) constant expansion, (3) a "volume law" for entanglement with respect to any partition into small parts. Second, we show that in several cases, good product-state approximations not only exist, but can be found in polynomial time: (1) 2-local Hamiltonians on any planar graph, solving an open problem of Bansal, Bravyi, and Terhal, (2) dense k-local Hamiltonians for any constant k, solving an open problem of Gharibian and Kempe, and (3) 2-local Hamiltonians on graphs with low threshold rank, via a quantum generalization of a recent result of Barak, Raghavendra and Steurer. Our work introduces two new tools which may be of independent interest. First, we prove a new quantum version of the de Finetti theorem which does not require the usual assumption of symmetry. Second, we describe a way to analyze the application of the Lasserre/Parrilo SDP hierarchy to local quantum Hamiltonians.

Fernando G. S. L. Brandão; Aram W. Harrow

2014-12-15T23:59:59.000Z

434

Crystallization of polyethylene by modified weighted density approximation(MWDA)  

E-Print Network [OSTI]

In this article, we use the modified weighted density approximation to study the crystallization of polyethylene. We also use a direct correlation function of polyethylene based on RISM theory. The free energy of a polyethylene is calculated using density functional theory. The crystallization and solid and liquid density are calculated and finally compared with the prism simulation and experimental results. That shown the result obtained by MWDA is in better agreement, compared with the experimental result than the prism.

Razeghizadeh, Alireza; Lavafpour, Farhad

2015-01-01T23:59:59.000Z

435

Crystallization of polyethylene by modified weighted density approximation(MWDA)  

E-Print Network [OSTI]

In this article, we use the modified weighted density approximation to study the crystallization of polyethylene. We also use a direct correlation function of polyethylene based on RISM theory. The free energy of a polyethylene is calculated using density functional theory. The crystallization and solid and liquid density are calculated and finally compared with the prism simulation and experimental results. That shown the result obtained by MWDA is in better agreement, compared with the experimental result than the prism.

Alireza Razeghizadeh; Vahdat Rafee; Farhad Lavafpour

2015-02-07T23:59:59.000Z

436

Nonlocal independent pixel approximation: Direct and inverse problems  

SciTech Connect (OSTI)

The independent pixel approximation (IPA), which treats radiative properties of each pixel independently by using standard plane-parallel calculations preserves scale-invariance found in the analyses of the horizontal variability of liquid water in marine stratocumulus clouds. Several studies, however, report a violation of scale-invariance in LANDSAT cloud radiance fields that are much smoother than cloud structure on small scales. This shows a limitation of IPA on small scales: it is unable to simulate the smooth small-scale behavior that is due to the horizontal photon transport. This paper introduces a nonlocal independent pixel approximation (NIPA) that extends the IPA by incorporating empirically the smoothing effects of horizontal interpixel fluxes through a convolution product of the IPA and an approximate Green function for radiative transfer. The authors also address the inverse problem of cloud optical depth retrieval from satellite data, showing how NIPA can be used to overcome the limitations of current IPA-based methods at small scales.

Marshak, A. [NASA Goddard Space Flight Center, Greenbelt, MD (United States). Climate and Radiation Branch] [NASA Goddard Space Flight Center, Greenbelt, MD (United States). Climate and Radiation Branch; [Univ. of Maryland Baltimore County, Baltimore, MD (United States). Joint Center for Earth Systems Technology; Davis, A. [NASA Goddard Space Flight Center, Greenbelt, MD (United States). Climate and Radiation Branch] [NASA Goddard Space Flight Center, Greenbelt, MD (United States). Climate and Radiation Branch; [Science Systems and Applications, Inc., Lanham, MD (United States); Cahalan, R.F.; Wiscombe, W. [NASA Goddard Space Flight Center, Greenbelt, MD (United States). Climate and Radiation Branch] [NASA Goddard Space Flight Center, Greenbelt, MD (United States). Climate and Radiation Branch

1998-01-01T23:59:59.000Z

437

The periodic standing-wave approximation: post-Minkowski computation  

E-Print Network [OSTI]

The periodic standing wave method studies circular orbits of compact objects coupled to helically symmetric standing wave gravitational fields. From this solution an approximation is extracted for the strong field, slowly inspiralling motion of black holes and binary stars. Previous work on this model has dealt with nonlinear scalar models, and with linearized general relativity. Here we present the results of the method for the post-Minkowski (PM) approximation to general relativity, the first step beyond linearized gravity. We compute the PM approximation in two ways: first, via the standard approach of computing linearized gravitational fields and constructing from them quadratic driving sources for second-order fields, and second, by solving the second-order equations as an ``exact'' nonlinear system. The results of these computations have two distinct applications: (i) The computational infrastructure for the ``exact'' PM solution will be directly applicable to full general relativity. (ii) The results will allow us to begin supplying initial data to collaborators running general relativistic evolution codes.

Christopher Beetle; Benjamin Bromley; Napoleón Hernández; Richard H. Price

2007-08-08T23:59:59.000Z

438

Modern testing meets wide range of objectives  

SciTech Connect (OSTI)

Testing sequences in two very different wells illustrate the wide range of objectives that are met with modern testing procedures. The first example is a drill stem test in an exploration well. The second test is in an established producing well. The exploration well test incorporated tubing-conveyed perforating, fluid sampling, production logging, and matrix stimulation to evaluate and properly treat near-well bore damage, as well as to investigate reservoir volume and characterize boundaries. The test on the established producer evaluated whether a workover could remedy lower than expected productivity. Production logging was combined with stationary transient measurements.

Ehlig-Economides, C.A.; Hegeman, P. (Schlumberger Oilfield Services, Houston, TX (United States)); Clark, G. (Schlumberger Oilfield Services, Aberdeen (United Kingdom))

1994-08-01T23:59:59.000Z

439

Optical range measurement system: principles and applications  

E-Print Network [OSTI]

modulated infrared beam from a LED to a targeted vehicle and receiving that being reflected, the relative distance between the host and target can be determined by the ORMS. There are basically two distinctive types of ORMS's. 1. Phase Shift ORMS... of the road, b. a vehicle parked on the shoulder of the highway, c. other targets in the scene within the effective range of the ranger. 14 A LED display could also be arranged to warn the driver, but this does not seem to be necessary. The driver may...

Roan, Tian-Ming Philip

1992-01-01T23:59:59.000Z

440

Short range correlations and the EMC effect  

SciTech Connect (OSTI)

The magnitude of the EMC effect measured in electron deep inelastic scattering (DIS) is linearly related to the Short Range Correlation (SRC) scaling factor obtained from electron inclusive scattering. We speculate that the observed correlation is due to the fact that both the EMC effect and SRC are dominated by high momentum nucleons in the nucleus. The observed phenomenological relationship can be used to extract the ratio of the deuteron to the free pn-pair cross sections, the DIS cross section for a free neutron, View the MathML source, the ratio of the free neutron to free proton structure functions, and the u/d ratio in a free proton.

E. Piasetzky, L.B. Weinstein, D.W. Higinbotham, J. Gomez, O. Hen, R. Shneor

2011-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "approximate boiling range" 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.


441

Rangely Oilfield Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentrating Solar PowerstoriesNrelPartnerType Jump to:Co JumpRETScreen Logo: Range Fuels Name:Jump

442

APS Long Range Schedule FY1996  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation Desert SouthwestTechnologies |November 2011Astudies ColoradoTechnical109)Long Range

443

APS Long Range Schedule FY1997  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation Desert SouthwestTechnologies |November 2011Astudies ColoradoTechnical109)Long Range7 Beamline

444

APS Long Range Schedule FY1998  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation Desert SouthwestTechnologies |November 2011Astudies ColoradoTechnical109)Long Range7 Beamline8

445

APS Long Range Schedule FY1999  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation Desert SouthwestTechnologies |November 2011Astudies ColoradoTechnical109)Long Range7

446

APS Long Range Schedule FY2001  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation Desert SouthwestTechnologies |November 2011Astudies ColoradoTechnical109)Long Range7

447

APS Long Range Schedule FY2002  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation Desert SouthwestTechnologies |November 2011Astudies ColoradoTechnical109)Long Range7

448

APS Long Range Schedule FY2004  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation Desert SouthwestTechnologies |November 2011Astudies ColoradoTechnical109)Long Range7

449

APS Long Range Schedule FY2005  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation Desert SouthwestTechnologies |November 2011Astudies ColoradoTechnical109)Long Range72005 Long

450

APS Long Range Schedule FY2006  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation Desert SouthwestTechnologies |November 2011Astudies ColoradoTechnical109)Long Range72005

451

Numerical Algorithms 16 (1997) 115 1 Sparse approximate inverse preconditioning  

E-Print Network [OSTI]

propagation phenomena to address various topics ranging from electromagnetic compatibility, to stealth, to absorbing materials, and antenna de- sign. Two complementary approaches based on the solution of the Maxwell

Benzi, Michele

452

E-Print Network 3.0 - approximate solution method Sample Search...  

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

numerical solution of partial differential... , Meshfree Approximation Methods with Matlab, Lecture Notes, IIT, 2005. Other required material... data approximation with radial...

453

E-Print Network 3.0 - approximate ensemble treatments Sample...  

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

assim- ilation system is that the ensemble approximates a ran- dom sample from the analysis pdf (HSM00... and the degree to which the ensemble approximates ... Source:...

454

Density Functional Theory with Correct Long-Range Asymptotic Behavior Roi Baer1,* and Daniel Neuhauser2,  

E-Print Network [OSTI]

Density Functional Theory with Correct Long-Range Asymptotic Behavior Roi Baer1,* and Daniel within density functional theory (DFT) which spawns a class of approximations leading to correct long.043002 PACS numbers: 31.15.Ew, 31.15.Ne, 31.25.Eb, 71.15.Mb Density functional theory (DFT) [1,2] is an in

Baer, Roi

455

Short range, ultra-wideband radar with high resolution swept range gate  

DOE Patents [OSTI]

A radar range finder and hidden object locator is based on ultra-wide band radar with a high resolution swept range gate. The device generates an equivalent time amplitude scan with a typical range of 4 inches to 20 feet, and an analog range resolution as limited by a jitter of on the order of 0.01 inches. A differential sampling receiver is employed to effectively eliminate ringing and other aberrations induced in the receiver by the near proximity of the transmit antenna, so a background subtraction is not needed, simplifying the circuitry while improving performance. Uses of the invention include a replacement of ultrasound devices for fluid level sensing, automotive radar, such as cruise control and parking assistance, hidden object location, such as stud and rebar finding. Also, this technology can be used when positioned over a highway lane to collect vehicle count and speed data for traffic control.

McEwan, Thomas E. (Livermore, CA)

1998-05-26T23:59:59.000Z

456

Short range, ultra-wideband radar with high resolution swept range gate  

DOE Patents [OSTI]

A radar range finder and hidden object locator is based on ultra-wide band radar with a high resolution swept range gate. The device generates an equivalent time amplitude scan with a typical range of 4 inches to 20 feet, and an analog range resolution as limited by a jitter of on the order of 0.01 inches. A differential sampling receiver is employed to effectively eliminate ringing and other aberrations induced in the receiver by the near proximity of the transmit antenna, so a background subtraction is not needed, simplifying the circuitry while improving performance. Uses of the invention include a replacement of ultrasound devices for fluid level sensing, automotive radar, such as cruise control and parking assistance, hidden object location, such as stud and rebar finding. Also, this technology can be used when positioned over a highway lane to collect vehicle count and speed data for traffic control. 14 figs.

McEwan, T.E.

1998-05-26T23:59:59.000Z

457

Ultra High Mass Range Mass Spectrometer System  

DOE Patents [OSTI]

Applicant's present invention comprises mass spectrometer systems that operate in a mass range from 1 to 10.sup.16 DA. The mass spectrometer system comprising an inlet system comprising an aerodynamic lens system, a reverse jet being a gas flux generated in an annulus moving in a reverse direction and a multipole ion guide; a digital ion trap; and a thermal vaporization/ionization detector system. Applicant's present invention further comprises a quadrupole mass spectrometer system comprising an inlet system having a quadrupole mass filter and a thermal vaporization/ionization detector system. Applicant's present invention further comprises an inlet system for use with a mass spectrometer system, a method for slowing energetic particles using an inlet system. Applicant's present invention also comprises a detector device and a method for detecting high mass charged particles.

Reilly, Peter T. A. [Knoxville, TN

2005-12-06T23:59:59.000Z

458

Scannerless loss modulated flash color range imaging  

DOE Patents [OSTI]

Scannerless loss modulated flash color range imaging methods and apparatus are disclosed for producing three dimensional (3D) images of a target within a scene. Apparatus and methods according to the present invention comprise a light source providing at least three wavelengths (passbands) of illumination that are each loss modulated, phase delayed and simultaneously directed to illuminate the target. Phase delayed light backscattered from the target is spectrally filtered, demodulated and imaged by a planar detector array. Images of the intensity distributions for the selected wavelengths are obtained under modulated and unmodulated (dc) illumination of the target, and the information contained in the images combined to produce a 3D image of the target.

Sandusky, John V. (Albuquerque, NM); Pitts, Todd Alan (Rio Rancho, NM)

2008-09-02T23:59:59.000Z

459

Scannerless loss modulated flash color range imaging  

DOE Patents [OSTI]

Scannerless loss modulated flash color range imaging methods and apparatus are disclosed for producing three dimensional (3D) images of a target within a scene. Apparatus and methods according to the present invention comprise a light source providing at least three wavelengths (passbands) of illumination that are each loss modulated, phase delayed and simultaneously directed to illuminate the target. Phase delayed light backscattered from the target is spectrally filtered, demodulated and imaged by a planar detector array. Images of the intensity distributions for the selected wavelengths are obtained under modulated and unmodulated (dc) illumination of the target, and the information contained in the images combined to produce a 3D image of the target.

Sandusky, John V. (Albuquerque, NM); Pitts, Todd Alan (Rio Rancho, NM)

2009-02-24T23:59:59.000Z

460

Short Range Correlations and the EMC Effect  

SciTech Connect (OSTI)

This Letter shows quantitatively that the magnitude of the EMC effect measured in electron deep inelastic scattering at intermediate xB, 0.35?xB?0.7, is linearly related to the short range correlation (SRC) scale factor obtained from electron inclusive scattering at xB?1. The observed phenomenological relationship is used to extract the ratio of the deuteron to the free pn pair cross sections and F2n/F2p, the ratio of the free neutron to free proton structure functions. We speculate that the observed correlation is because both the EMC effect and SRC are dominated by the high virtuality (high momentum) nucleons in the nucleus.

L.B. Weinstein, E. Piasetzky, D.W. Higinbotham, J. Gomez, O. Hen, R. Shneor

2011-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "approximate boiling range" 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.


461

Short Range Correlations and the EMC Effect  

E-Print Network [OSTI]

This paper shows quantitatively that the magnitude of the EMC effect measured in electron deep inelastic scattering (DIS) at intermediate $x_B$, $0.35\\le x_B\\le 0.7$, is linearly related to the Short Range Correlation (SRC) scaling factor obtained from electron inclusive scattering at $x_B\\ge 1.$. The observed phenomenological relationship is used to extract the ratio of the deuteron to the free $pn$ pair cross sections, the DIS cross section for a free neutron, and $F_2^n/F_2^p$, the ratio of the free neutron to free proton structure functions. We speculate that the observed correlation is because both the EMC effect and SRC are dominated by the high virtuality (high momentum) nucleons in the nucleus.

L. B. Weinstein; E. Piasetzky; D. W. Higinbotham; J. Gomez; O. Hen; R. Shneor

2011-01-18T23:59:59.000Z

462

Short Range Correlations and the EMC Effect  

SciTech Connect (OSTI)

This Letter shows quantitatively that the magnitude of the EMC effect measured in electron deep inelastic scattering at intermediate x{sub B}, 0.35{<=}x{sub B{<=}}0.7, is linearly related to the short range correlation (SRC) scale factor obtained from electron inclusive scattering at x{sub B{>=}}1. The observed phenomenological relationship is used to extract the ratio of the deuteron to the free pn pair cross sections and F{sub 2}{sup n}/F{sub 2}{sup p}, the ratio of the free neutron to free proton structure functions. We speculate that the observed correlation is because both the EMC effect and SRC are dominated by the high virtuality (high momentum) nucleons in the nucleus.

Weinstein, L. B. [Old Dominion University, Norfolk, Virginia 23529 (United States); Piasetzky, E.; Hen, O.; Shneor, R. [Tel Aviv University, Tel Aviv 69978 (Israel); Higinbotham, D. W.; Gomez, J. [Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606 (United States)

2011-02-04T23:59:59.000Z

463

Nondipole effects in the photoionization of neon: Random-phase approximation  

SciTech Connect (OSTI)

The random-phase approximation (RPA) is applied to study nondipole corrections to the angular distribution of photoelectrons from the n=2 shell of Ne. Calculations of the parameters {gamma}{sub nl} and {delta}{sub nl} arising from E{sub 1}-E{sub 2} interference effects are carried out for the 2s and 2p subshells of Ne in the photon energy range 100{endash}2000 eV. For the 2s shell, the RPA calculations show small effects of correlation near the 2s threshold energy, but are otherwise in agreement with independent-particle approximation (IPA) calculations. The RPA and IPA values of {gamma}{sub 2s} are also in agreement with experiment. For the 2p shell, a small difference between RPA and IPA calculations of the nondipole parameters is found for energies near the 1s threshold; however, both RPA and IPA calculations of the parameter {gamma}{sub 2p}+3{delta}{sub 2p} disagree significantly with experimental measurements for photon energies above 1000 eV. thinsp {copyright} {ital 1999} {ital The American Physical Society}

Johnson, W.R.; Derevianko, A. [Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556 (United States)] [Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556 (United States); Cheng, K.T. [Lawrence Livermore National Laboratory, University of California, Livermore, California 94550 (United States)] [Lawrence Livermore National Laboratory, University of California, Livermore, California 94550 (United States); Dolmatov, V.K.; Manson, S.T. [Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303 (United States)] [Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303 (United States)

1999-05-01T23:59:59.000Z

464

Thermally-assisted-occupation density functional theory with generalized-gradient approximations  

SciTech Connect (OSTI)

We extend the recently proposed thermally-assisted-occupation density functional theory (TAO-DFT) [J.-D. Chai, J. Chem. Phys. 136, 154104 (2012)] to generalized-gradient approximation (GGA) exchange-correlation density functionals. Relative to our previous TAO-LDA (i.e., the local density approximation to TAO-DFT), the resulting TAO-GGAs are significantly superior for a wide range of applications, such as thermochemistry, kinetics, and reaction energies. For noncovalent interactions, TAO-GGAs with empirical dispersion corrections are shown to yield excellent performance. Due to their computational efficiency for systems with strong static correlation effects, TAO-LDA and TAO-GGAs are applied to study the electronic properties (e.g., the singlet-triplet energy gaps, vertical ionization potentials, vertical electron affinities, fundamental gaps, and symmetrized von Neumann entropy) of acenes with different number of linearly fused benzene rings (up to 100), which is very challenging for conventional electronic structure methods. The ground states of acenes are shown to be singlets for all the chain lengths studied here. With the increase of acene length, the singlet-triplet energy gaps, vertical ionization potentials, and fundamental gaps decrease monotonically, while the vertical electron affinities and symmetrized von Neumann entropy (i.e., a measure of polyradical character) increase monotonically.

Chai, Jeng-Da, E-mail: jdchai@phys.ntu.edu.tw [Department of Physics, Center for Theoretical Sciences, and Center for Quantum Science and Engineering, National Taiwan University, Taipei 10617, Taiwan (China)] [Department of Physics, Center for Theoretical Sciences, and Center for Quantum Science and Engineering, National Taiwan University, Taipei 10617, Taiwan (China)

2014-05-14T23:59:59.000Z

465

Adsorption of molecular gases on porous materials in the SAFT-VR approximation  

E-Print Network [OSTI]

A simple molecular thermodynamic approach is applied to the study of the adsorption of gases of chain molecules on solid surfaces. We use a model based on the Statistical Associating Fluid Theory for Variable Range (SAFT-VR) potentials [A. Gil-Villegas, A. Galindo, P. J. Whitehead, S. J. Mills, G. Jackson, A. N. Burgess, J. Chem. Phys. 106 (1997) 4168] that we extend by including a quasi-two-dimensional approximation to describe the adsorption properties of this type of real gases [A. Martinez, M. Castro, C. McCabe, A. Gil-Villegas, J. Chem. Phys. 126 (2007) 074707]. The model is applied to ethane, ethylene, propane, and carbon dioxide adsorbed on activated carbon and silica gel, which are porous media of significant industrial interest. We show that the adsorption isotherms obtained by means of the present SAFT-VR modeling are in fair agreement with the experimental results provided in the literature

Castro, M; Martinez, A; Rosu, H C; 10.1016/j.physa.2010.04.028

2010-01-01T23:59:59.000Z

466

Complete equation of state for neutron stars using the relativistic Hartree-Fock approximation  

SciTech Connect (OSTI)

We construct the equation of state in a wide-density range for neutron stars within relativistic Hartree-Fock approximation. The properties of uniform and nonuniform nuclear matter are studied consistently. The tensor couplings of vector mesons to baryons due to exchange contributions (Fock terms) are included, and the change of baryon internal structure in matter is also taken into account using the quark-meson coupling model. The Thomas-Fermi calculation is adopted to describe nonuniform matter, where the lattice of nuclei and the neutron drip out of nuclei are considered. Even if hyperons exist in the core of a neutron star, we obtain the maximum neutron-star mass of 1.95M{sub ?}, which is consistent with the recently observed massive pulsar, PSR J1614-2230. In addition, the strange vector (?) meson also plays a important role in supporting a massive neutron star.

Miyatsu, Tsuyoshi; Cheoun, Myung-Ki [Department of Physics, Soongsil University, Seoul 156-743 (Korea, Republic of); Yamamuro, Sachiko; Nakazato, Ken'ichiro [Department of Physics, Faculty of Science and Technology, Tokyo University of Science (TUS), Noda 278-8510 (Japan)

2014-05-02T23:59:59.000Z

467

Continuum quasiparticle random phase approximation for astrophysical direct neutron capture reaction of neutron-rich nuclei  

E-Print Network [OSTI]

We formulate a many-body theory to calculate the cross section of direct radiative neutron capture reaction by means of the Hartree-Fock-Bogoliubov mean-field model and the continuum quasiparticle random phase approximation (QRPA). A focus is put on very neutron-rich nuclei and low-energy neutron kinetic energy in the range of O(1 keV) - O(1 MeV), relevant for the rapid neutron-capture process of nucleosynthesis. We begin with the photo-absorption cross section and the E1 strength function, then, in order to apply the reciprocity theorem, we decompose the cross section into partial cross sections corresponding to different channels of one- and two-neutron emission decays of photo-excited states. Numerical example is shown for the photo-absorption of $^{142}$Sn and the neutron capture of $^{141}$Sn.

Masayuki Matsuo

2014-10-31T23:59:59.000Z

468

Gaussian approximation to the condensation of the interacting Bose gas  

E-Print Network [OSTI]

The effective action formalism of quantum field theory is used to study the properties of the non-relativistic interacting Bose gas. The Gaussian approximation is formulated by calculating the effective action to the first order of the optimized expansion. In the homogeneous limit the method respects the Hughenholz-Pines theorem, leading to the gapless spectrum both for excitations and for density fluctuations. Renormalization is carried out by adopting dimensional regularization. The results for critical temperature are compared with that obtained in the loop expansion.

Anna Okopi?ska

2003-09-29T23:59:59.000Z

469

Approximation Theorems Related to the Coupon Collector's Problem  

E-Print Network [OSTI]

This Ph.D. thesis concerns the version of the classical coupon collector's problem, when a collector samples with replacement a set of $n\\ge 2$ distinct coupons so that at each time any one of the $n$ coupons is drawn with the same probability $1/n$. For a fixed integer $m\\in\\{0,1,\\ldots,n-1\\}$, the coupon collector's waiting time $W_{n,m}$ is the random number of draws the collector performs until he acquires $n-m$ distinct coupons for the first time. The basic goal of the thesis is to approximate the distribution of the coupon collector's appropriately centered and normalized waiting time with well-known measures with high accuracy, and in many cases prove asymptotic expansions for the related probability distribution functions and mass functions. The approximating measures are chosen from five different measure families. Three of them -- the Poisson distributions, the normal distributions and the Gumbel-like distributions -- are probability measure families whose members occur as limiting laws in the limit...

Pósfai, Anna

2010-01-01T23:59:59.000Z

470

Cross sections for electron scattering by propane in the low- and intermediate-energy ranges  

SciTech Connect (OSTI)

We present a joint theoretical-experimental study on electron scattering by propane (C{sub 3}H{sub 8}) in the low- and intermediate-energy ranges. Calculated elastic differential, integral, and momentum transfer as well as total (elastic + inelastic) and total absorption cross sections are reported for impact energies ranging from 2 to 500 eV. Also, experimental absolute elastic cross sections are reported in the 40- to 500-eV energy range. A complex optical potential is used to represent the electron-molecule interaction dynamics. A theoretical method based on the single-center-expansion close-coupling framework and corrected by the Pade approximant is used to solve the scattering equations. The experimental angular distributions of the scattered electrons are converted to absolute cross sections using the relative flow technique. The comparison of our calculated with our measured results, as well as with other experimental and theoretical data available in the literature, is encouraging.

Souza, G. L. C. de; Lee, M.-T.; Sanches, I. P.; Rawat, P.; Iga, I.; Santos, A. S. dos; Machado, L. E.; Sugohara, R. T.; Brescansin, L. M.; Homem, M. G. P.; Lucchese, R. R. [Departamento de Quimica, UFSCar, 13565-905 Sao Carlos, SP (Brazil); Departamento de Fisica, UFSCar, 13565-905 Sao Carlos, SP (Brazil); Instituto de Fisica 'Gleb Wataghin', UNICAMP, 13083-970 Campinas, SP (Brazil); Departamento de Fisica, UFSC, 88010-970 Florianopolis, SC (Brazil); Department of Chemistry, Texas A and M University, College Station, Texas 7784-3255 (United States)

2010-07-15T23:59:59.000Z

471

Range Sustainability (VSP) PNWD-SA-7032 1  

E-Print Network [OSTI]

Range Sustainability (VSP) PNWD-SA-7032 1 PNWD-SA-7032 Range Sustainability Module Using Visual Sample Plan (VSP) Software Range Sustainability ModuleRange Sustainability Module Using Visual Sample Sustainability (VSP) PNWD-SA-7032 2 PNWD-SA-7032 / 2 ObjectiveObjectiveObjective Learn how to use the Range

472

AINVK: a Class of Approximate Inverse Preconditioners based on ...  

E-Print Network [OSTI]

Similarly, several real applications, ranging from power systems ..... The previous lemma yields a technical condition which is used in the next proposition, in order to strongly reinforce item ...... 6.1 On the assessment of the bound (6.6). In order ...

2012-09-13T23:59:59.000Z

473

Learning and Value Function Approximation in Complex Decision Processes  

E-Print Network [OSTI]

of the requirements for the degree of Doctor of Philosophy at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY June 1998 c of Doctor of Philosophy Abstract In principle, a wide variety of sequential decision problems ranging from dynamic resource allocation in telecommunication networks to nancial risk management can be formulated

Van Roy, Ben

474

Importance of Delayed Neutrons on the Coupled Neutronic-Thermohydraulic Stability of a Natural Circulation Heavy Water-Moderated Boiling Light Water-Cooled Reactor  

SciTech Connect (OSTI)

The coupled neutronic-thermohydraulic stability characteristics of a natural circulation heavy water-moderated boiling light water-cooled reactor was investigated analytically considering the effects of prompt and delayed neutrons. For this purpose, the reactor considered is the Indian Advanced Heavy Water Reactor. The analytical model considers a point kinetics model for the neutron dynamics, a homogeneous two-phase flow model for the coolant thermal hydraulics, and a lumped heat transfer model for the fuel thermal dynamics. A higher mode of oscillation having a frequency much greater than the density-wave oscillation frequency was observed if prompt neutrons alone were considered. The occurrence of a higher mode of oscillation was found to be dependent on the concentration of delayed neutrons, the void reactivity coefficient, and the fuel time constant. The core inlet subcooling is found to have different effects on the decay ratio of the fundamental and higher modes of oscillations. The influences of void reactivity coefficient and fuel time constant on the fundamental and higher modes of oscillations were also found to be opposite in nature.

Nayak, A.K. [Bhaha Atomic Research Centre (India); Aritomi, M. [Tokyo Institute of Technology (Japan); Raj, V. Venkat [Bhaha Atomic Research Centre (India)

2001-07-15T23:59:59.000Z

475

Technology, safety and costs of decommissioning a reference boiling water reactor power station: Technical support for decommissioning matters related to preparation of the final decommissioning rule  

SciTech Connect (OSTI)

Preparation of the final Decommissioning Rule by the Nuclear Regulatory Commission (NRC) staff has been assisted by Pacific Northwest Laboratory (PNL) staff familiar with decommissioning matters. These efforts have included updating previous cost estimates developed during the series of studies of conceptually decommissioning reference licensed nuclear facilities for inclusion in the Final Generic Environmental Impact Statement (FGEIS) on decommissioning; documenting the cost updates; evaluating the cost and dose impacts of post-TMI-2 backfits on decommissioning; developing a revised scaling formula for estimating decommissioning costs for reactor plants different in size from the reference boiling water reactor (BWR) described in the earlier study; and defining a formula for adjusting current cost estimates to reflect future escalation in labor, materials, and waste disposal costs. This report presents the results of recent PNL studies to provide supporting information in three areas concerning decommissioning of the reference BWR: updating the previous cost estimates to January 1986 dollars; assessing the cost and dose impacts of post-TMI-2 backfits; and developing a scaling formula for plants different in size than the reference plant and an escalation formula for adjusting current cost estimates for future escalation.

Konzek, G.J.; Smith, R.I.

1988-07-01T23:59:59.000Z

476

On Corrections to the Born-Oppenheimer Approximation  

E-Print Network [OSTI]

This report presents a new approach for treating the coupling of electrons and nuclei in quantum mechanical calculations for molecules and condensed matter. It includes the standard "Born-Oppenheimer approximation" as a special case but treats both adiabatic and non-adiabatic corrections using perturbation theory. The adiabatic corrections include all terms that do not explicitly involve the nuclear wavefunctions, so that the nuclei move on a single electronic potential surface. The non-adiabatic corrections, which allow the nuclei to move on more than one potential surface, include coupling between the electronic and nuclear wavefunctions. The method is related to an approach first proposed by Born and Huang, but it differs in the methodology and in the definition of the electronic wavefunctions and potential surfaces. A simple example is worked out to illustrate the mechanics of the technique. The report also includes a review of previous work.

Gerald I. Kerley

2013-06-24T23:59:59.000Z

477

Fast quantum algorithms for approximating some irreducible representations of groups  

E-Print Network [OSTI]

We consider the quantum complexity of estimating matrix elements of unitary irreducible representations of groups. For several finite groups including the symmetric group, quantum Fourier transforms yield efficient solutions to this problem. Furthermore, quantum Schur transforms yield efficient solutions for certain irreducible representations of the unitary group. Beyond this, we obtain poly(n)-time quantum algorithms for approximating matrix elements from all the irreducible representations of the alternating group A_n, and all the irreducible representations of polynomial highest weight of U(n), SU(n), and SO(n). These quantum algorithms offer exponential speedup in worst case complexity over the fastest known classical algorithms. On the other hand, we show that average case instances are classically easy, and that the techniques analyzed here do not offer a speedup over classical computation for the estimation of group characters.

Stephen P. Jordan

2009-04-21T23:59:59.000Z

478

Quantifier elimination for approximate Beals-Kartashova factorization  

E-Print Network [OSTI]

The only known constructive factorization algorithm for linear partial differential operators (LPDOs) is Beals-Kartashova (BK) factorization \\cite{bk2005}. One of the most interesting features of BK-factorization: at the beginning all the first-order factors are constructed and afterwards the factorization condition(s) should be checked. This leads to the important application area - namely, numerical simulations which could be simplified substantially if instead of computation with one LPDE of order $n$ we will be able to proceed computations with $n$ LPDEs all of order 1. In numerical simulations it is not necessary to fulfill factorization conditions exactly but with some given accuracy, which we call approximate factorization. The idea of the present paper is to look into the feasibility of solving problems of this kind using quantifier elinination by cylindrical algebraic decomposition.

Elena Kartashova; Scott McCallum

2007-01-07T23:59:59.000Z

479

ANALYTIC APPROXIMATION OF CARBON CONDENSATION ISSUES IN TYPE II SUPERNOVAE  

SciTech Connect (OSTI)

I present analytic approximations for some issues related to condensation of graphite, TiC, and silicon carbide in oxygen-rich cores of supernovae of Type II. Increased understanding, which mathematical analysis can support, renders researchers more receptive to condensation in O-rich supernova gases. Taking SN 1987A as typical, my first analysis shows why the abundance of CO molecules reaches an early maximum in which free carbon remains more abundant than CO. This analysis clarifies why O-rich gas cannot oxidize C if {sup 56}Co radioactivity is as strong as in SN 1987A. My next analysis shows that the CO abundance could be regarded as being in chemical equilibrium if the CO molecule is given an effective binding energy rather than its laboratory dissociation energy. The effective binding energy makes the thermal dissociation rate of CO equal to its radioactive dissociation rate. This preserves possible relevance for the concept of chemical equilibrium. My next analysis shows that the observed abundances of CO and SiO molecules in SN 1987A rule out frequent suggestions that equilibrium condensation of SUNOCONs has occurred following atomic mixing of the He-burning shell with more central zones in such a way as to reproduce roughly the observed spectrum of isotopes in SUNOCONs while preserving C/O > 1. He atoms admixed along with the excess carbon would destroy CO and SiO molecules, leaving their observed abundances unexplained. The final analysis argues that a chemical quasiequilibrium among grains (but not gas) may exist approximately during condensation, so that its computational use is partially justified as a guide to which mineral phases would be stable against reactions with gas. I illustrate this point with quasiequilibrium calculations by Ebel and Grossman that have shown that graphite is stable even when O/C >1 if prominent molecules are justifiably excluded from the calculation of chemical equilibrium.

Clayton, Donald D., E-mail: claydonald@gmail.com [Department of Physics and Astronomy, Clemson University, Clemson, SC (United States)

2013-01-01T23:59:59.000Z

480

Describing long-range charge-separation processes with subsystem density-functional theory  

SciTech Connect (OSTI)

Long-range charge-transfer processes in extended systems are difficult to describe with quantum chemical methods. In particular, cost-effective (non-hybrid) approximations within time-dependent density functional theory (DFT) are not applicable unless special precautions are taken. Here, we show that the efficient subsystem DFT can be employed as a constrained DFT variant to describe the energetics of long-range charge-separation processes. A formal analysis of the energy components in subsystem DFT for such excitation energies is presented, which demonstrates that both the distance dependence and the long-range limit are correctly described. In addition, electronic couplings for these processes as needed for rate constants in Marcus theory can be obtained from this method. It is shown that the electronic structure of charge-separated states constructed by a positively charged subsystem interacting with a negatively charged one is difficult to converge — charge leaking from the negative subsystem to the positive one can occur. This problem is related to the delocalization error in DFT and can be overcome with asymptotically correct exchange–correlation (XC) potentials or XC potentials including a sufficiently large amount of exact exchange. We also outline an approximate way to obtain charge-transfer couplings between locally excited and charge-separated states.

Solovyeva, Alisa; Neugebauer, Johannes, E-mail: j.neugebauer@uni-muenster.de [Theoretische Organische Chemie, Organisch-Chemisches Institut and Center for Multiscale Theory and Simulation, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster (Germany)] [Theoretische Organische Chemie, Organisch-Chemisches Institut and Center for Multiscale Theory and Simulation, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149 Münster (Germany); Pavanello, Michele, E-mail: m.pavanello@rutgers.edu [Department of Chemistry, Rutgers University, 73 Warren St., Newark, New Jersey 07102 (United States)] [Department of Chemistry, Rutgers University, 73 Warren St., Newark, New Jersey 07102 (United States)

2014-04-28T23:59:59.000Z

Note: This page contains sample records for the topic "approximate boiling range" 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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481

Regional And Local Trends In Helium Isotopes, Basin And Range...  

Open Energy Info (EERE)

Range Province, Western North America- Evidence For Deep Permeable Pathways Abstract Fluids from the western margin of the Basin and Range have helium isotope ratios as high as...

482

T-710: Apache HTTP Server Overlapping Ranges Denial of Service...  

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

0: Apache HTTP Server Overlapping Ranges Denial of Service Vulnerability T-710: Apache HTTP Server Overlapping Ranges Denial of Service Vulnerability September 6, 2011 - 3:09am...

483

Geographic Information System At Northern Basin & Range Region...  

Open Energy Info (EERE)

Activity: Geographic Information System At Northern Basin & Range Region (Nash & Johnson, 2003) Exploration Activity Details Location Northern Basin and Range Geothermal...

484

Geographic Information System At Nw Basin & Range Region (Nash...  

Open Energy Info (EERE)

Geographic Information System At Nw Basin & Range Region (Nash & Johnson, 2003) Exploration Activity Details Location Northwest Basin and Range Geothermal Region Exploration...

485

Synergy between Secondary Organic Aerosols and Long Range Transport...  

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

between Secondary Organic Aerosols and Long Range Transport of Polycyclic Aromatic Hydrocarbons. Synergy between Secondary Organic Aerosols and Long Range Transport of Polycyclic...

486

Teleseismic-Seismic Monitoring At Nw Basin & Range Region (Biasi...  

Open Energy Info (EERE)

Teleseismic-Seismic Monitoring At Nw Basin & Range Region (Biasi, Et Al., 2008) Exploration Activity Details Location Northwest Basin and Range Geothermal Region Exploration...

487

Molecular dynamics simulations of ion range profiles for heavy...  

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

simulations of ion range profiles for heavy ions in light targets. Molecular dynamics simulations of ion range profiles for heavy ions in light targets. Abstract: The determination...

488

Compact, Convex Upper Bound Iteration for Approximate POMDP Planning  

E-Print Network [OSTI]

uncertainty How to act based on past experience Maximize long term reward Wide range of applications Robotics and autonomous agent design Helicopter control, Robot navigation and mapping Nursing , Elderly assistance Others #12;POMDP model s0 s0 a1 a1 o1 o1 s1 s1 s2 s2 a2 a2 o2 o2 st st at at ot ot r0 r0 r1 r1 r2 r2 rt rt

Wang, Tao

489

Multilevel summation methods for efficient evaluation of long-range pairwise interactions in atomistic and coarse-grained molecular simulation.  

SciTech Connect (OSTI)

The availability of efficient algorithms for long-range pairwise interactions is central to the success of numerous applications, ranging in scale from atomic-level modeling of materials to astrophysics. This report focuses on the implementation and analysis of the multilevel summation method for approximating long-range pairwise interactions. The computational cost of the multilevel summation method is proportional to the number of particles, N, which is an improvement over FFTbased methods who's cost is asymptotically proportional to N logN. In addition to approximating electrostatic forces, the multilevel summation method can be use to efficiently approximate convolutions with long-range kernels. As an application, we apply the multilevel summation method to a discretized integral equation formulation of the regularized generalized Poisson equation. Numerical results are presented using an implementation of the multilevel summation method in the LAMMPS software package. Preliminary results show that the computational cost of the method scales as expected, but there is still a need for further optimization.

Bond, Stephen D.

2014-01-01T23:59:59.000Z

490

The Kormendy Relation for early-type galaxies. Dependence on the magnitude range  

E-Print Network [OSTI]

Previous studies indicate that faint and bright early-type galaxies (ETGs) present different coefficients and dispersion for their Kormendy relation (KR). A recently published paper states that the intrinsic dispersion of the KR depends on the magnitude range within which the galaxies are contained, therefore, we investigate here whether the magnitude range has also an influence over the values of the coefficients of the KR; $\\alpha$ (zero point) and $\\beta$ (slope). We perform numerical simulations and analysis of these coefficients for 4 samples of galaxies, which contain an approximate total of 9400 ETGs in a relatively ample magnitude range ($$ $\\sim 6 mag$). The analysis of the results makes us conclude that the values of the KR coefficients depend on the width of the magnitude range and the brightness of galaxies within the magnitude range. This dependence is due to the fact that the distribution of galaxies in the $\\log (r_{e}) - _{e}$ plane depends on luminosity and that this distribution is not symmetrical, that is, the geometric shape of the distribution of galaxies in the $\\log (r_{e}) - _{e}$ plane plays an important role in the determination of the values of the coefficients of the KR.

A. Nigoche-Netro; A. Ruelas-Mayorga; A. Franco-Balderas

2008-09-17T23:59:59.000Z

491

Moment Closure Approximations in a Genetic Negative Feedback Circuit  

E-Print Network [OSTI]

Auto-regulation, a process wherein a protein negatively regulates its own production, is a common motif in gene expression networks. Negative feedback in gene expression plays a critical role in buffering intracellular fluctuations in protein concentrations around optimal value. Due to the nonlinearities present in these feedbacks, moment dynamics are typically not closed, in the sense that the time derivative of the lower-order statistical moments of the protein copy number depends on high-order moments. Moment equations are closed by expressing higher-order moments as nonlinear functions of lower-order moments, a technique commonly referred to as moment closure. Here, we compare the performance of different moment closure techniques. Our results show that the commonly used closure method, which assumes a priori that the protein population counts are normally distributed, performs poorly. In contrast, conditional derivative matching, a novel closure scheme proposed here provides a good approximation to the exact moments across different parameter regimes. In summary our study provides a new moment closure method for studying stochastic dynamics of genetic negative feedback circuits, and can be extended to probe noise in more complex gene networks.

Mohammad Soltani; Cesar Vargas; Niraj Kumar; Rahul Kulkarni; Abhyudai Singh

2014-05-15T23:59:59.000Z

492

Light Water Reactor Sustainability Program Support and Modeling for the Boiling Water Reactor Station Black Out Case Study Using RELAP and RAVEN  

SciTech Connect (OSTI)

The existing fleet of nuclear power plants is in the process of extending its lifetime and increasing the power generated. In order to evaluate the impact of these two factors on the safety of the plant, the Risk Informed Safety Margin Characterization (RISMC) project aims to provide insight to decision makers through a series of simulations of the plant dynamics for different initial conditions (e.g., probabilistic analysis and uncertainty quantification). This report focuses, in particular, on the impact of power uprate on the safety of a boiled water reactor system. The case study considered is a loss of off-site power followed by the loss of diesel generators, i.e., a station black out (SBO) event. Analysis is performed by using a thermo-hydraulic code, i.e. RELAP-5, and a stochastic analysis tool currently under development at INL, i.e. RAVEN. Starting from the event tree models contained in SAPHIRE, we built the input file for RELAP-5 that models in great detail system dynamics under SBO conditions. We also interfaced RAVEN with RELAP-5 so that it would be possible to run multiple RELAP-5 simulation runs by changing specific keywords of the input file. We both employed classical statistical tools, i.e. Monte-Carlo, and more advanced machine learning based algorithms to perform uncertainty quantification in order to quantify changes in system performance and limitations as a consequence of power uprate. We also employed advanced data analysis and visualization tools that helped us to correlate simulation outcome such as maximum core temperature with a set of input uncertain parameters. Results obtained gave a detailed overview of the issues associated to power uprate for a SBO accident scenario. We were able to quantify how timing of safety related events were impacted by a higher reactor core power. Such insights can provide useful material to the decision makers to perform risk-infomed safety margins management.

Diego Mandelli; Curtis Smith; Thomas Riley; John Schroeder; Cristian Rabiti; Aldrea Alfonsi; Joe Nielsen; Dan Maljovec; Bie Wang; Valerio Pascucci

2013-09-01T23:59:59.000Z

493

The DF-4 fuel damage experiment in ACRR (Annual Core Research Reactor) with a BWR (Boiling Water Reactor) control blade and channel box  

SciTech Connect (OSTI)

The DF-4 test was an experimental investigation into the melt progression behavior of boiling water reactor (BWR) core components under high temperature severe core damage conditions. In this study 14 zircaloy clad UO{sub 2} fuel rods, and representations of the zircaloy fuel canister and stainless steel/B{sub 4}C control blade were assembled into a 0.5 m long test bundle. The test bundle was fission heated in a flowing steam environment, using the Annular Core Research Reactor at Sandia Laboratories, simulating the environmental conditions of an uncovered BWR core experiencing high temperature damage as a result residual fission product decay heating. The experimental results provide information on the thermal response of the test bundle components, the rapid exothermic oxidation of the zircaloy fuel cladding and canister, the production of hydrogen from metal-steam oxidation, and the failure behavior of the progressively melting bundle components. This information is provided in the form of thermocouple data, steam and hydrogen flow rate data, test bundle fission power data and visual observation of the damage progression. In addition to BWR background information, this document contains a description of the experimental hardware with details on how the experiment was instrumented and diagnosed, a description of the test progression, and a presentation of the on-line measurements. Also in this report are the results of a thermal analysis of the fueled test section of the fueled test section of the experiment demonstrating an overall consistency in the measurable quantities from the test. A discussion of the results is provided. 38 refs., 72 figs., 7 tabs.

Gauntt, R.O.; Gasser, R.D.; Ott, L.J. (Sandia National Labs., Albuquerque, NM (USA))

1989-11-01T23:59:59.000Z

494

E-Print Network 3.0 - approximate l-state solutions Sample Search...  

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

where C... 'o','x','+'. Omit C for a connected graph. APPROXIMATE SOLUTIONS The matlab commands eul, rk2, and rk4 can be used... to obtain approximate solutions of the ......

495

Low-rank approximations with sparse factors II: penalized methods with discrete Newton-like iterations  

E-Print Network [OSTI]

H. Zha, and H. Simon. Low-rank Approximations with Sparse5) H. Simon and H. Zhao Low-rank matrix approximation usingZhang. Matrices with low-rank-plus-shift structure: partial

Simon, Horst

2011-01-01T23:59:59.000Z

496

A 1:52-Approximation Algorithm for the Uncapacitated Facility Location Problem  

E-Print Network [OSTI]

A 1:52-Approximation Algorithm for the Uncapacitated Facility Location Problem Mohammad Mahdian #3: Approximation Algorithms for UFLP 2 Algorithm In [5], Jain, Mahdian, and Saberi proposed a greedy algorithm

Ye, Yinyu

497

Autonomous Vehicles Have a Wide Range of Possible Energy Impacts (Poster)  

SciTech Connect (OSTI)

This poster presents initial estimates of the net energy impacts of automated vehicles (AVs). Automated vehicle technologies are increasingly recognized as having potential to decrease carbon dioxide emissions and petroleum consumption through mechanisms such as improved efficiency, better routing, lower traffic congestion, and by enabling advanced technologies. However, some effects of AVs could conceivably increase fuel consumption through possible effects such as longer distances traveled, increased use of transportation by underserved groups, and increased travel speeds. The net effect on petroleum use and climate change is still uncertain. To make an aggregate system estimate, we first collect best estimates for the energy impacts of approximately ten effects of AVs. We then use a modified Kaya Identity approach to estimate the range of aggregate effects and avoid double counting. We find that depending on numerous factors, there is a wide range of potential energy impacts. Adoption of automated personal or shared vehicles can lead to significant fuel savings but has potential for backfire.

Brown, A.; Repac, B.; Gonder, J.

2013-07-01T23:59:59.000Z

498

Information resources management long-range plan, FY1994--1998  

SciTech Connect (OSTI)

This document describes IRM activities and the information technology resources and capabilities of the Department, the future requirements, and the strategies and plans to satisfy the identified requirements. The long-range planning process provides the systematic means to meet this objective and assists the Department in assuring that information technology (IT) support is provided in an efficient, effective, and timely manner so that its programmatic missions can be accomplished. Another important objective of the Plan is to promote better understanding, both within and external to the Department, of its IT environment, requirements, issues, and recommended solutions. This DOE IRM Plan takes into consideration the IRM requirements of approximately 50 different sites. The annual long-range planning cycle for supporting this Plan was initiated by a Call in August 1991 for site plans to be submitted in February 1992 by those Departmental components and contractors with major IRM requirements.

Not Available

1993-04-01T23:59:59.000Z

499

Markov Jump Processes Approximating a Non-Symmetric Generalized Diffusion  

SciTech Connect (OSTI)

Consider a non-symmetric generalized diffusion X( Dot-Operator ) in Double-Struck-Capital-R {sup d} determined by the differential operator A(x) = -{Sigma}{sub ij} {partial_derivative}{sub i}a{sub ij}(x){partial_derivative}{sub j} + {Sigma}{sub i} b{sub i}(x){partial_derivative}{sub i}. In this paper the diffusion process is approximated by Markov jump processes X{sub n}( Dot-Operator ), in homogeneous and isotropic grids G{sub n} Subset-Of Double-Struck-Capital-R {sup d}, which converge in distribution in the Skorokhod space D([0,{infinity}), Double-Struck-Capital-R {sup d}) to the diffusion X( Dot-Operator ). The generators of X{sub n}( Dot-Operator ) are constructed explicitly. Due to the homogeneity and isotropy of grids, the proposed method for d{>=}3 can be applied to processes for which the diffusion tensor {l_brace}a{sub ij}(x){r_brace}{sub 11}{sup dd} fulfills an additional condition. The proposed construction offers a simple method for simulation of sample paths of non-symmetric generalized diffusion. Simulations are carried out in terms of jump processes X{sub n}( Dot-Operator ). For piece-wise constant functions a{sub ij} on Double-Struck-Capital-R {sup d} and piece-wise continuous functions a{sub ij} on Double-Struck-Capital-R {sup 2} the construction and principal algorithm are described enabling an easy implementation into a computer code.

Limic, Nedzad, E-mail: nlimic@math.hr [University of Zagreb, Dept. of Mathematics (Croatia)

2011-08-15T23:59:59.000Z

500

3D Scattered Data Approximation with Adaptive Compactly Supported Radial Basis Functions  

E-Print Network [OSTI]

¾ ¼ ½ indicating the confidence of � . Our aim is to construct a function Ý ´�µ such that its zero level-set ´�µ , � �, we construct ´�µ approximating � in the follow- ing form suggested in [27] ¾ ´�µ · ´ � µ approximation of �. For each approximation center , we construct ´�µ as a local quadratic approximation of �

Kazhdan, Michael