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1

Helium circulator design considerations for modular high temperature gas-cooled reactor plant  

SciTech Connect

Efforts are in progress to develop a standard modular high temperature gas-cooled reactor (MHTGR) plant that is amenable to design certification and serial production. The MHTGR reference design, based on a steam cycle power conversion system, utilizes a 350 MW(t) annular reactor core with prismatic fuel elements. Flexibility in power rating is afforded by utilizing a multiplicity of the standard module. The circulator, which is an electric motor-driven helium compressor, is a key component in the primary system of the nuclear plant, since it facilitates thermal energy transfer from the reactor core to the steam generator; and, hence, to the external turbo-generator set. This paper highlights the helium circulator design considerations for the reference MHTGR plant and includes a discussion on the major features of the turbomachine concept, operational characteristics, and the technology base that exists in the U.S.

McDonald, C.F.; Nichols, M.K.

1987-01-01T23:59:59.000Z

2

Helium circulator design considerations for modular high temperature gas-cooled reactor plant  

SciTech Connect

Efforts are in progress to develop a standard modular high temperature gas-cooled reactor (MHTGR) plant that is amenable to design certification and serial production. The MHTGR reference design, based on a steam cycle power conversion system, utilizes a 350 MW(t) annular reactor core with prismatic fuel elements. Flexibility in power rating is afforded by utilizing a multiplicity of the standard module. The circulator, which is an electric motor-driven helium compressor, is a key component in the primary system of the nuclear plant, since it facilitates thermal energy transfer from the reactor core to the steam generator; and, hence, to the external turbo-generator set. This paper highlights the helium circulator design considerations for the reference MHTGR plant and includes a discussion on the major features of the turbomachine concept, operational characteristics, and the technology base that exists in the US.

McDonald, C.F.; Nichols, M.K.

1986-12-01T23:59:59.000Z

3

The gas turbine-modular helium reactor (GT-MHR), high efficiency, cost competitive, nuclear energy for the next century  

SciTech Connect

The Gas Turbine-Modular Helium Reactor (GT-MHR) is the result of coupling the evolution of a small passively safe reactor with key technology developments in the US during the last decade: large industrial gas turbines, large active magnetic bearings, and compact, highly effective plate-fin heat exchangers. The GT-MHR is the only reactor concept which provides a step increase in economic performance combined with increased safety. This is accomplished through its unique utilization of the Brayton cycle to produce electricity directly with the high temperature helium primary coolant from the reactor directly driving the gas turbine electrical generator. This cannot be accomplished with another reactor concept. It retains the high levels of passive safety and the standardized modular design of the steam cycle MHTGR, while showing promise for a significant reduction in power generating costs by increasing plant net efficiency to a remarkable 47%.

Zgliczynski, J.B.; Silady, F.A.; Neylan, A.J.

1994-04-01T23:59:59.000Z

4

SRS Small Modular Reactors  

SciTech Connect

The small modular reactor program at the Savannah River Site and the Savannah River National Laboratory.

None

2012-04-27T23:59:59.000Z

5

SRS Small Modular Reactors  

ScienceCinema (OSTI)

The small modular reactor program at the Savannah River Site and the Savannah River National Laboratory.

None

2014-05-21T23:59:59.000Z

6

Modularity of the MIT Pebble Bed Reactor for use by the commercial power industry  

E-Print Network (OSTI)

The Modular Pebble Bed Reactor is a small high temperature helium cooled reactor that is being considered for both electric power and hydrogen production. Pebble bed reactors are being developed in South Africa, China and ...

Hanlon-Hyssong, Jaime E

2008-01-01T23:59:59.000Z

7

Small Modular Nuclear Reactors | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Reactor Technologies » Small Modular Reactor Technologies » Small Modular Nuclear Reactors Small Modular Nuclear Reactors Cutaway of 2-Unit Generation mPower SMR Installation. | © 2012 Generation mPower LLC. All Rights Reserved. Reprinted with permission. Cutaway of 2-Unit Generation mPower SMR Installation. | © 2012 Generation mPower LLC. All Rights Reserved. Reprinted with permission. The development of clean, affordable nuclear power options is a key element of the Department of Energy's Office of Nuclear Energy (DOE-NE) Nuclear Energy Research and Development Roadmap. As a part of this strategy, a high priority of the Department has been to help accelerate the timelines for the commercialization and deployment of small modular reactor (SMR) technologies through the SMR Licensing Technical Support program. Begun

8

Ordered bed modular reactor design proposal  

SciTech Connect

The Ordered Bed Modular Reactor (OBMR) is a design as an advanced modular HTGR in which the annular reactor core is filled with an ordered bed of fuel spheres. This arrangement allows fuel elements to be poured into the core cavity which is shaped so that an ordered bed is formed and to be discharged from the core through the opening holes in the reactor top. These operations can be performed in a shutdown shorter time. The OBMR has the most of advantages from both the pebble bed reactor and block type reactor. Its core has great structural flexibility and stability, which allow increasing reactor output power and outlet gas temperature as well as decreasing core pressure drop. This paper introduces ordered packing bed characteristics, unloading and loading technique of the fuel spheres and predicted design features of the OBMR. (authors)

Tian, J. [Inst. of Nuclear Energy Technology, Tsinghua Univ., Beijing 100084 (China)

2006-07-01T23:59:59.000Z

9

Computational Analysis of Fluid Flow in Pebble Bed Modular Reactor  

E-Print Network (OSTI)

High Temperature Gas-cooled Reactor (HTGR) is a Generation IV reactor under consideration by Department of Energy and in the nuclear industry. There are two categories of HTGRs, namely, Pebble Bed Modular Reactor (PBMR) and Prismatic reactor. Pebble...

Gandhir, Akshay

2012-10-19T23:59:59.000Z

10

Modular Pebble Bed Reactor High Temperature Gas Reactor  

E-Print Network (OSTI)

Modular Pebble Bed Reactor High Temperature Gas Reactor Andrew C Kadak Massachusetts Institute For 1150 MW Combined Heat and Power Station Oil Refinery Hydrogen Production Desalinization Plant VHTR/Graphite Discrimination system Damaged Sphere ContainerGraphiteReturn FuelReturn Fresh Fuel Container Spent Fuel Tank #12

11

Small Modular Reactors (468th Brookhaven Lecture)  

SciTech Connect

With good reason, much more media attention has focused on nuclear power plants than solar farms, wind farms, or hydroelectric plants during the past month and a half. But as nations around the world demand more energy to power everything from cell phone batteries to drinking water pumps to foundries, nuclear plants are the only non-greenhouse-gas producing option that can be built to operate almost anywhere, and can continue to generate power during droughts, after the sun sets, and when winds die down. To supply this demand for power, designers around the world are competing to develop more affordable nuclear reactors of the future: small modular reactors. Brookhaven Lab is working with DOE to ensure that these reactors are designed to be safe for workers, members of surrounding communities, and the environment and to ensure that the radioactive materials and technology will only be used for peaceful purposes, not weapons. In his talk, Bari will discuss the advantages and challenges of small modular reactors and what drives both international and domestic interest in them. He will also explain how Brookhaven Lab and DOE are working to address the challenges and provide a framework for small modular reactors to be commercialized.

Bari, Robert

2011-04-20T23:59:59.000Z

12

Baseline Concept Description of a Small Modular High Temperature Reactor  

SciTech Connect

The objective of this report is to provide a description of generic small modular high temperature reactors (herein denoted as an smHTR), summarize their distinguishing attributes, and lay out the research and development (R&D) required for commercialization. The generic concepts rely heavily on the modular high temperature gas-cooled reactor designs developed in the 1980s which were never built but for which pre-licensing or certification activities were conducted. The concept matured more recently under the Next Generation Nuclear Plant (NGNP) project, specifically in the areas of fuel and material qualification, methods development, and licensing. As all vendor-specific designs proposed under NGNP were all both small or medium-sized and modular by International Atomic Energy Agency (IAEA) and Department of Energy (DOE) standards, the technical attributes, challenges, and R&D needs identified, addressed, and documented under NGNP are valid and appropriate in the context of Small Modular Reactor (SMR) applications. Although the term High Temperature Reactor (HTR) is commonly used to denote graphite-moderated, thermal spectrum reactors with coolant temperatures in excess of 650oC at the core outlet, in this report the historical term High Temperature Gas-Cooled Reactor (HTGR) will be used to distinguish the gas-cooled technology described herein from its liquid salt-cooled cousin. Moreover, in this report it is to be understood that the outlet temperature of the helium in an HTGR has an upper limit of 950 degrees C which corresponds to the temperature to which certain alloys are currently being qualified under DOEs ARC program. Although similar to the HTGR in just about every respect, the Very High Temperature Reactor (VHTR) may have an outlet temperature in excess of 950 degrees C and is therefore farther from commercialization because of the challenges posed to materials exposed to these temperatures. The VHTR is the focus of R&D under the Generation IV program and its specific R&D needs will be included in this report when appropriate for comparison. The distinguishing features of the HTGR are the refractory (TRISO) coated particle fuel, the low-power density, graphite-moderated core, and the high outlet temperature of the inert helium coolant. The low power density and fuel form effectively eliminate the possibility of core melt, even upon a complete loss of coolant pressure and flow. The graphite, which constitutes the bulk of the core volume and mass, provides a large thermal buffer that absorbs fission heat such that thermal transients occur over a timespan of hours or even days. As chemically-inert helium is already a gas, there is no coolant temperature or void feedback on the neutronics and no phase change or corrosion product that could degrade heat transfer. Furthermore, the particle coatings and interstitial graphite retain fission products such that the source terms at the plant boundary remain well below actionable levels under all anticipated nominal and off-normal operating conditions. These attributes enable the reactor to supply process heat to a collocated industrial plant with negligible risk of contamination and minimal dynamic coupling of the facilities (Figure 1). The exceptional retentive properties of coated particle fuel in a graphite matrix were first demonstrated in the DRAGON reactor, a European research facility that began operation in 1964.

Hans Gougar

2014-05-01T23:59:59.000Z

13

Economic Aspects of Small Modular Reactors  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Economic Aspects of Small Modular Reactors March 1, 2012 Introduction The potential for SMR deployment will be largely determined by the economic value that these power plants would provide to interested power producers who would evaluate their prospects in relation to other options for generating electricity. To help better understand this proposition, DOE enlisted the Energy Policy Institute at Chicago in 2010 to conduct an economic analysis of SMRs based upon what is known today. Their findings were summarized in a paper by Robert Rosner and Stephen Goldberg, released in December, 2011, titled "Small Modular Reactors - Key to Future Nuclear Power Generation in the U.S." This brief paper will highlight some of the key finding from the study

14

Small Modular Reactors Presentation to Secretary of Energy Advisory...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Presentation to Secretary of Energy Advisory Board - Deputy Assistant Secretary John Kelly Small Modular Reactors Presentation to Secretary of Energy Advisory Board - Deputy...

15

Generic small modular reactor plant design.  

SciTech Connect

This report gives an overview of expected design characteristics, concepts, and procedures for small modular reactors. The purpose of this report is to provide those who are interested in reducing the cost and improving the safety of advanced nuclear power plants with a generic design that possesses enough detail in a non-sensitive manner to give merit to their conclusions. The report is focused on light water reactor technology, but does add details on what could be different in a more advanced design (see Appendix). Numerous reactor and facility concepts were used for inspiration (documented in the bibliography). The final design described here is conceptual and does not reflect any proposed concept or sub-systems, thus any details given here are only relevant within this report. This report does not include any design or engineering calculations.

Lewis, Tom Goslee,; Cipiti, Benjamin B.; Jordan, Sabina Erteza; Baum, Gregory A.

2012-12-01T23:59:59.000Z

16

MODULAR PEBBLE BED REACTOR PROJECT UNIVERSITY RESEARCH CONSORTIUM  

E-Print Network (OSTI)

Annual Report Page ii MODULAR PEBBLE BED REACTOR ABSTRACT This project is developing a fundamental. Publication of an archival journal article covering this work is being prepared. · Detailed gas reactor Abstract

17

Human Reliability Analysis for Small Modular Reactors  

SciTech Connect

Because no human reliability analysis (HRA) method was specifically developed for small modular reactors (SMRs), the application of any current HRA method to SMRs represents tradeoffs. A first- generation HRA method like THERP provides clearly defined activity types, but these activity types do not map to the human-system interface or concept of operations confronting SMR operators. A second- generation HRA method like ATHEANA is flexible enough to be used for SMR applications, but there is currently insufficient guidance for the analyst, requiring considerably more first-of-a-kind analyses and extensive SMR expertise in order to complete a quality HRA. Although no current HRA method is optimized to SMRs, it is possible to use existing HRA methods to identify errors, incorporate them as human failure events in the probabilistic risk assessment (PRA), and quantify them. In this paper, we provided preliminary guidance to assist the human reliability analyst and reviewer in understanding how to apply current HRA methods to the domain of SMRs. While it is possible to perform a satisfactory HRA using existing HRA methods, ultimately it is desirable to formally incorporate SMR considerations into the methods. This may require the development of new HRA methods. More practicably, existing methods need to be adapted to incorporate SMRs. Such adaptations may take the form of guidance on the complex mapping between conventional light water reactors and small modular reactors. While many behaviors and activities are shared between current plants and SMRs, the methods must adapt if they are to perform a valid and accurate analysis of plant personnel performance in SMRs.

Ronald L. Boring; David I. Gertman

2012-06-01T23:59:59.000Z

18

Proliferation resistance of small modular reactors fuels  

SciTech Connect

In this paper the proliferation resistance of different types of Small Modular Reactors (SMRs) has been examined and classified with criteria available in the literature. In the first part of the study, the level of proliferation attractiveness of traditional low-enriched UO{sub 2} and MOX fuels to be used in SMRs based on pressurized water technology has been analyzed. On the basis of numerical simulations both cores show significant proliferation risks. Although the MOX core is less proliferation prone in comparison to the UO{sub 2} core, it still can be highly attractive for diversion or undeclared production of nuclear material. In the second part of the paper, calculations to assess the proliferation attractiveness of fuel in typical small sodium cooled fast reactor show that proliferation risks from spent fuel cannot be neglected. The core contains a highly attractive plutonium composition during the whole life cycle. Despite some aspects of the design like the sealed core that enables easy detection of unauthorized withdrawal of fissile material and enhances proliferation resistance, in case of open Non-Proliferation Treaty break-out, weapon-grade plutonium in sufficient quantities could be extracted from the reactor core.

Polidoro, F.; Parozzi, F. [RSE - Ricerca sul Sistema Energetico,Via Rubattino 54, 20134, Milano (Italy); Fassnacht, F.; Kuett, M.; Englert, M. [IANUS, Darmstadt University of Technology, Alexanderstr. 35, D-64283 Darmstadt (Germany)

2013-07-01T23:59:59.000Z

19

Small Modular Reactors Presentation to Secretary of Energy Advisory Board -  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Small Modular Reactors Presentation to Secretary of Energy Advisory Small Modular Reactors Presentation to Secretary of Energy Advisory Board - Deputy Assistant Secretary John Kelly Small Modular Reactors Presentation to Secretary of Energy Advisory Board - Deputy Assistant Secretary John Kelly DOE Small Modular Reactor Program (SMR) Research, Development & Deployment (RD&D) to enable the deployment of a fleet of SMRs in the United States SMR Program is a new program for FY 2011 Structured to address the need to enable the deployment of mature, near-term SMR designs based on known LWR technology Conduct needed R&D activities to advance the understanding and demonstration of innovative reactor technologies and concepts John_Kelly-SEAB_SMRBriefing_July20_2011_final.pdf More Documents & Publications Meeting Materials: June 12, 2012

20

Energy Department Announces Small Modular Reactor Technology Partnerships  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Small Modular Reactor Technology Small Modular Reactor Technology Partnerships at Savannah River Site Energy Department Announces Small Modular Reactor Technology Partnerships at Savannah River Site March 2, 2012 - 10:27am Addthis WASHINGTON, D.C. -- The U.S. Energy Department and its Savannah River Site (SRS) announced today three public-private partnerships to develop deployment plans for small modular nuclear reactor (SMR) technologies at SRS facilities, near Aiken, South Carolina. As part of the Energy Department's commitment to advancing the next generation of nuclear reactor technologies and breaking down the technical and economic barriers to deployment, these Memorandums of Agreement (MOA) will help leverage Savannah River's land assets, energy facilities and nuclear expertise to

Note: This page contains sample records for the topic "modular helium reactor" 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

Economic Aspects of Small Modular Reactors | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Economic Aspects of Small Modular Reactors Economic Aspects of Small Modular Reactors Economic Aspects of Small Modular Reactors The potential for SMR deployment will be largely determined by the economic value that these power plants would provide to interested power producers who would evaluate their prospects in relation to other options for generating electricity. To help better understand this proposition, DOE enlisted the Energy Policy Institute at Chicago in 2010 to conduct an economic analysis of SMRs based upon what is known today. Their findings were summarized in a paper by Robert Rosner and Stephen Goldberg, released in December, 2011, titled "Small Modular Reactors - Key to Future Nuclear Power Generation in the U.S." This brief paper will highlight some of the key finding from the study1

22

Cost-Shared Development of Innovative Small Modular Reactor Designs |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Cost-Shared Development of Innovative Small Modular Reactor Designs Cost-Shared Development of Innovative Small Modular Reactor Designs Cost-Shared Development of Innovative Small Modular Reactor Designs The Small Modular Reactor (SMR) Licensing Technical Support (LTS) program, sponsored by the U.S. Department of Energy (DOE) Office of Nuclear Energy (NE), through this Funding Opportunity Announcement (FOA) seeks to facilitate the development of innovative SMR designs that have the potential to address the nation's economic, environmental and energy security goals. Specifically, the Department is soliciting applications for SMR designs that offer unique and innovative solutions for achieving the objectives of enhanced safety, operations, and performance relative to currently certified designs. This FOA focuses on design development and

23

Economic Aspects of Small Modular Reactors | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Economic Aspects of Small Modular Reactors Economic Aspects of Small Modular Reactors Economic Aspects of Small Modular Reactors The potential for SMR deployment will be largely determined by the economic value that these power plants would provide to interested power producers who would evaluate their prospects in relation to other options for generating electricity. To help better understand this proposition, DOE enlisted the Energy Policy Institute at Chicago in 2010 to conduct an economic analysis of SMRs based upon what is known today. Their findings were summarized in a paper by Robert Rosner and Stephen Goldberg, released in December, 2011, titled "Small Modular Reactors - Key to Future Nuclear Power Generation in the U.S." This brief paper will highlight some of the key finding from the study1

24

Cost-Shared Development of Innovative Small Modular Reactor Designs |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Cost-Shared Development of Innovative Small Modular Reactor Designs Cost-Shared Development of Innovative Small Modular Reactor Designs Cost-Shared Development of Innovative Small Modular Reactor Designs The Small Modular Reactor (SMR) Licensing Technical Support (LTS) program, sponsored by the U.S. Department of Energy (DOE) Office of Nuclear Energy (NE), through this Funding Opportunity Announcement (FOA) seeks to facilitate the development of innovative SMR designs that have the potential to address the nation's economic, environmental and energy security goals. Specifically, the Department is soliciting applications for SMR designs that offer unique and innovative solutions for achieving the objectives of enhanced safety, operations, and performance relative to currently certified designs. This FOA focuses on design development and

25

Partnerships Help Advance Small Modular Reactor Technology | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Partnerships Help Advance Small Modular Reactor Technology Partnerships Help Advance Small Modular Reactor Technology Partnerships Help Advance Small Modular Reactor Technology March 5, 2012 - 12:00pm Addthis WASHINGTON, D.C. - DOE recently announced three public-private partnerships to develop deployment plans for small modular nuclear reactor (SMR) technologies at Savannah River Site (SRS) facilities near Aiken, S.C. Read the full story on the Memorandums of Agreement to help leverage SRS land assets, energy facilities and nuclear expertise to support potential private sector development, testing and licensing of prototype SMR technologies. Addthis Related Articles Energy Department Announces Small Modular Reactor Technology Partnerships at Savannah River Site The development of clean, affordable nuclear power options is a key element of the Energy Department's Nuclear Energy Research and Development Roadmap. As a part of this strategy, a high priority of the Department has been to help accelerate the timelines for the commercialization and deployment of small modular reactor (SMR) technologies through the SMR Licensing Technical Support program. | Photo by the Energy Department.

26

ANALYSIS OF SEPCTRUM CHOICES FOR SMALL MODULAR REACTORS-PERFORMANCE AND DEVELOPMENT  

E-Print Network (OSTI)

. The research mainly focused on producing a small modular reactor (Pebble Bed Modular Reactor) design to analyze the fuel depletion and plutonium and minor actinide accumulation with varying power densities. The reactors running at low power densities were found...

Kafle, Nischal

2011-04-26T23:59:59.000Z

27

Human Reliability Considerations for Small Modular Reactors  

SciTech Connect

Small modular reactors (SMRs) are a promising approach to meeting future energy needs. Although the electrical output of an individual SMR is relatively small compared to that of typical commercial nuclear plants, they can be grouped to produce as much energy as a utility demands. Furthermore, SMRs can be used for other purposes, such as producing hydrogen and generating process heat. The design characteristics of many SMRs differ from those of current conventional plants and may require a distinct concept of operations. The U.S. Nuclear Regulatory Commission (NRC) conducted research to examine the human factors engineering and the operational aspects of SMRs. The research identified thirty potential human-performance issues that should be considered in the NRC's reviews of SMR designs and in future research activities. The purpose of this report is to illustrate how the issues can support SMR probabilistic risk analyses and their review by identifying potential human failure events for a subset of the issues. As part of addressing the human contribution to plant risk, human reliability analysis practitioners identify and quantify the human failure events that can negatively impact normal or emergency plant operations. The results illustrated here can be generalized to identify additional human failure events for the issues discussed and can be applied to those issues not discussed in this report.

OHara J. M.; Higgins, H.; DAgostino, A.; Erasmia, L.

2012-01-27T23:59:59.000Z

28

Advancing Small Modular Reactors: How We're Supporting Next-Gen...  

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

Advancing Small Modular Reactors: How We're Supporting Next-Gen Nuclear Energy Technology Advancing Small Modular Reactors: How We're Supporting Next-Gen Nuclear Energy Technology...

29

Development of a system model for advanced small modular reactors.  

SciTech Connect

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

Lewis, Tom Goslee,; Holschuh, Thomas Vernon,

2014-01-01T23:59:59.000Z

30

Steam reformers heated by helium from high temperature reactors  

Science Journals Connector (OSTI)

The manifold possibilities of the application of helium-heated steam reformers combined with high temperature nuclear reactors are elucidated in this article. It is shown that the thermodynamic interpretation of the processes does not cause difficulties because of the good heat transfer in helium at high pressure and that helium peak temperatures of 950C are sufficient for carrying out the process. The mechanical design of the reformer tube does not lead to problems because the helium and process pressures are so chosen as to be approximately equal. The problems of hydrogen and tritium permeation as well as the contamination of the reformer tube with solid fission products seem to be solvable using the knowledge available at present. Furthermore, the various possibilities for the design arrangements of helium-heated reformer tube furnaces are shown. The status of development attained to date is outlined and in conclusion there is a survey regarding the next steps to be taken in steam reformer technology.

K. Kugeler; M. Kugeler; H.F. Niessen; K.H. Hammelmann

1975-01-01T23:59:59.000Z

31

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

SciTech Connect

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

S. Bragg-Sitton

2014-10-01T23:59:59.000Z

32

Multiple reheat helium Brayton cycles for sodium fast reactors  

SciTech Connect

Sodium fast reactors (SFR) traditionally adopt the steam Rankine cycle for power conversion. The resulting potential for water-sodium reaction remains a continuing concern which at least partly delays the SFR technology commercialization and is a contributor to higher capital cost. Supercritical CO2 provides an alternative, but is also capable of sustaining energetic chemical reactions with sodium. Recent development on advanced inert-gas Brayton cycles could potentially solve this compatibility issue, increase thermal efficiency, and bring down the capital cost close to light water reactors. In this paper, helium Brayton cycles with multiple reheat and intercooling states are presented for SFRs with reactor outlet temperatures in the range of 510C to 650C. The resulting thermal efficiencies range from 39% and 47%, which is comparable with supercritical recompression CO2 cycles (SCO2 cycle). A systematic comparison between multiple reheat helium Brayton cycle and the SCO2 cycle is given, considering compatibility issues, plant site cooling temperature effect on plant efficiency, full plant cost optimization, and other important factors. The study indicates that the multiple reheat helium cycle is the preferred choice over SCO2 cycle for sodium fast reactors.

Haihua Zhao; Per F. Peterson

2008-07-01T23:59:59.000Z

33

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

SciTech Connect

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

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

2014-03-01T23:59:59.000Z

34

Advancing Small Modular Reactors: How We're Supporting Next-Gen Nuclear  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Advancing Small Modular Reactors: How We're Supporting Next-Gen Advancing Small Modular Reactors: How We're Supporting Next-Gen Nuclear Energy Technology Advancing Small Modular Reactors: How We're Supporting Next-Gen Nuclear Energy Technology December 12, 2013 - 4:00pm Addthis The basics of small modular reactor technology explained. | Infographic by Sarah Gerrity, Energy Department. The basics of small modular reactor technology explained. | Infographic by Sarah Gerrity, Energy Department. Assistant Secretary Lyons Assistant Secretary Lyons Assistant Secretary for Nuclear Energy Nuclear energy continues to be an important part of America's diverse energy portfolio, and the Energy Department is committed to supporting a domestic nuclear industry.

35

Safety aspects of the Modular High-Temperature Gas-Cooled Reactor (MHTGR)  

SciTech Connect

The Modular High-Temperature Gas-Cooled Reactor (MHTGR) is an advanced reactor concept under development through a cooperative program involving the US Government, the nuclear industry and the utilities. The design utilizes the basic high-temperature gas-cooled reactor (HTGR) features of ceramic fuel, helium coolant, and a graphite moderator. The qualitative top-level safety requirement is that the plant's operation not disturb the normal day-to-day activities of the public. The MHTGR safety response to events challenging the functions relied on to retain radionuclides within the coated fuel particles has been evaluated. A broad range of challenges to core heat removal have been examined which include a loss of helium pressure and a simultaneous loss of forced cooling of the core. The challenges to control of heat generation have considered not only the failure to insert the reactivity control systems, but the withdrawal of control rods. Finally, challenges to control chemical attack of the ceramic coated fuel have been considered, including catastrophic failure of the steam generator allowing water ingress or of the pressure vessels allowing air ingress. The plant's response to these extreme challenges is not dependent on operator action and the events considered encompass conceivable operator errors. In the same vein, reliance on radionuclide retention within the full particle and on passive features to perform a few key functions to maintain the fuel within acceptable conditions also reduced susceptibility to external events, site-specific events, and to acts of sabotage and terrorism. 4 refs., 14 figs., 1 tab.

Silady, F.A.; Millunzi, A.C.

1989-08-01T23:59:59.000Z

36

Modular Inspection System for a Complete IN-Service Examination of Nuclear Reactor Pressure Vessel, Including Beltline Region  

SciTech Connect

Final Report for a DOE Phase II Contract Describing the design and fabrication of a reactor inspection modular rover prototype for reactor vessel inspection.

David H. Bothell

2000-04-30T23:59:59.000Z

37

Small Modular Reactors and U.S. Clean Energy Sources for Electricity |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Small Modular Reactors and U.S. Clean Energy Sources for Small Modular Reactors and U.S. Clean Energy Sources for Electricity Small Modular Reactors and U.S. Clean Energy Sources for Electricity For the clean energy goal to be met, then, the non-carbon emitting sources must provide some 2900 TWhr. Hydropower is generally assumed to have reached a maximum of 250 TWhr, so if we assume renewables reach 650 TWhr, (double the EIA estimate) that leaves 2000 TWhr for nuclear power. If the Administration's loan guarantee program for current large reactors is successful, then one might expect the large reactors to reach 1000 TWhr by 2035. This leaves some 1000 TWhr for SMR - that is a lot of electricity. SMR and Clean Energy.pdf More Documents & Publications Slide 1 Small Modular Reactor Report (SEAB) A Strategic Framework for SMR Deployment

38

An Overview of the Safety Case for Small Modular Reactors  

SciTech Connect

Several small modular reactor (SMR) designs emerged in the late 1970s and early 1980s in response to lessons learned from the many technical and operational challenges of the large Generation II light-water reactors. After the accident at the Three Mile Island plant in 1979, an ensuing reactor redesign effort spawned the term inherently safe designs, which later evolved into passively safe terminology. Several new designs were engineered to be deliberately small in order to fully exploit the benefits of passive safety. Today, new SMR designs are emerging with a similar philosophy of offering highly robust and resilient designs with increased safety margins. Additionally, because these contemporary designs are being developed subsequent to the September 11, 2001, terrorist attack, they incorporate a number of intrinsic design features to further strengthen their safety and security. Several SMR designs are being developed in the United States spanning the full spectrum of reactor technologies, including water-, gas-, and liquid-metal-cooled ones. Despite a number of design differences, most of these designs share a common set of design principles to enhance plant safety and robustness, such as eliminating plant design vulnerabilities where possible, reducing accident probabilities, and mitigating accident consequences. An important consequence of the added resilience provided by these design approaches is that the individual reactor units and the entire plant should be able to survive a broader range of extreme conditions. This will enable them to not only ensure the safety of the general public but also help protect the investment of the owner and continued availability of the power-generating asset. Examples of typical SMR design features and their implications for improved plant safety are given for specific SMR designs being developed in the United States.

Ingersoll, Daniel T [ORNL] [ORNL

2011-01-01T23:59:59.000Z

39

Small Modular Fast Reactor Design Description Joint Effort  

NLE Websites -- All DOE Office Websites (Extended Search)

July 1, 2005 ANL-SMFR-1 July 1, 2005 ANL-SMFR-1 Small Modular Fast Reactor Design Description Joint Effort by Argonne National Laboratory (ANL) Commissariat a l'Energie Atomique (CEA) and Japan Nuclear Cycle Development Institute (JNC) Project Leaders Y. I. Chang and C. Grandy, ANL P. Lo Pinto, CEA M. Konomura, JNC Technical Contributors ANL: J. Cahalan, F. Dunn, M. Farmer, S. Kamal, L. Krajtl, A. Moisseytsev, Y. Momozaki, J. Sienicki, Y. Park, Y. Tang, C. Reed, C. Tzanos, S. Wiedmeyer, and W. Yang CEA: P. Allegre, J. Astegiano, F. Baque, L. Cachon, M. S. Chenaud, J-L Courouau, Ph. Dufour, J. C. Klein, C. Latge, C. Thevenot, and F. Varaine JNC: M. Ando, Y. Chikazawa, M. Nagamura, Y. Okano, Y. Sakamoto,

40

Proliferation resistant fuel for pebble bed modular reactors  

SciTech Connect

We show that it is possible to denature the Plutonium produced in Pebble Bed Modular Reactors (PBMR) by doping the nuclear fuel with either 3050 ppm of {sup 237}Np or 2100 ppm of Am vector. A correct choice of these isotopes concentration yields denatured Plutonium with isotopic ratio {sup 238}Pu/Pu {>=} 6%, for the entire fuel burnup cycle. The penalty for introducing these isotopes into the nuclear fuel is a subsequent shortening of the fuel burnup cycle, with respect to a non-doped reference fuel, by 41.2 Full Power Days (FPDs) and 19.9 FPDs, respectively, which correspond to 4070 MWd/ton and 1965 MWd/ton reduction in fuel discharge burnup. (authors)

Ronen, Y.; Aboudy, M.; Regev, D.; Gilad, E. [Dept. of Nuclear Engineering, Ben-Gurion Univ. of the Negev, Beer-Sheva 84105 (Israel)

2012-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "modular helium reactor" 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

Advanced Small Modular Reactor (SMR) Probabilistic Risk Assessment (PRA) Demonstration  

SciTech Connect

A key area of the Advanced Small Modular Reactor (SMR) Probabilistic Risk Assessment (PRA) strategy is the development of methodologies and tools that will be used to predict the safety, security, safeguards, performance, and deployment viability of SMRs. The goal of the SMR PRA activity will be to develop quantitative methods and tools and the associated analysis framework for assessing a variety of risks. Development and implementation of SMR-focused safety assessment methods may require new analytic methods or adaptation of traditional methods to the advanced design and operational features of SMRs. We will need to move beyond the current limitations such as static, logic-based models in order to provide more integrated, scenario-based models based upon predictive modeling which are tied to causal factors. The development of SMR-specific safety models for margin determination will provide a safety case that describes potential accidents, design options (including postulated controls), and supports licensing activities by providing a technical basis for the safety envelope. This report documents the progress that was made to implement the PRA framework, specifically by way of demonstration of an advanced 3D approach to representing, quantifying and understanding flooding risks to a nuclear power plant.

Curtis Smith; Steven Prescott; Tony Koonce

2014-04-01T23:59:59.000Z

42

Energy Department Announces New Investment in U.S. Small Modular Reactor  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Investment in U.S. Small Modular Investment in U.S. Small Modular Reactor Design and Commercialization Energy Department Announces New Investment in U.S. Small Modular Reactor Design and Commercialization November 20, 2012 - 2:48pm Addthis News Media Contact (202) 586-4940 WASHINGTON - As part of the Obama Administration's all-of-the-above strategy to deploy every available source of American energy, the Energy Department today announced an award to support a new project to design, license and help commercialize small modular reactors (SMR) in the United States. This award follows a funding opportunity announcement in March 2012. The project supported by the award will be led by Babcock & Wilcox (B&W) in partnership with the Tennessee Valley Authority and Bechtel. In addition, the Department announced plans to issue a follow-on solicitation

43

First Step to Spur U.S. Manufacturing of Small Modular Nuclear Reactors |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

First Step to Spur U.S. Manufacturing of Small Modular Nuclear First Step to Spur U.S. Manufacturing of Small Modular Nuclear Reactors First Step to Spur U.S. Manufacturing of Small Modular Nuclear Reactors January 25, 2012 - 5:06pm Addthis Brenda DeGraffenreid The Energy Department recently announced the first step toward manufacturing small modular nuclear reactors (SMRs) in the United States, demonstrating the Administration's commitment to advancing U.S. manufacturing leadership in low-carbon, next generation energy technologies and restarting the nation's nuclear industry. The release of a draft Funding Opportunity Announcement (FOA) last week presents supply-chain procurement opportunities for our nation's small businesses down the line, as industry provides input in advance of a full FOA on engineering, design certification, and licensing through a

44

Secretary Chu Op-Ed on Small Modular Reactors in the Wall Street Journal |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Op-Ed on Small Modular Reactors in the Wall Street Op-Ed on Small Modular Reactors in the Wall Street Journal Secretary Chu Op-Ed on Small Modular Reactors in the Wall Street Journal March 23, 2010 - 12:00am Addthis Washington, D.C. - Today, the Wall Street Journal published an op-ed by U.S. Secretary of Energy Steven Chu on small modular reactors. The op-ed can be viewed on the Wall Street Journal. The text of the op-ed is below: America's New Nuclear Option Small modular reactors will expand the ways we use atomic power. By Steven Chu Wall Street Journal, March 23, 2010 America is on the cusp of reviving its nuclear power industry. Last month President Obama pledged more than $8 billion in conditional loan guarantees for what will be the first U.S. nuclear power plant to break ground in nearly three decades. And with the new authority granted by the president's

45

Secretary Chu's Op-Ed on Small Modular Reactors in the Wall Street Journal  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Secretary Chu's Op-Ed on Small Modular Reactors in the Wall Street Secretary Chu's Op-Ed on Small Modular Reactors in the Wall Street Journal Secretary Chu's Op-Ed on Small Modular Reactors in the Wall Street Journal March 23, 2010 - 12:24pm Addthis Washington, D.C. - Today, the Wall Street Journal published an op-ed by U.S. Secretary of Energy Steven Chu on small modular reactors. The op-ed can be found here. The text of the op-ed is below: Small modular reactors will expand the ways we use atomic power. By Steven Chu, Secretary of Energy Wall Street Journal America is on the cusp of reviving its nuclear power industry. Last month President Obama pledged more than $8 billion in conditional loan guarantees for what will be the first U.S. nuclear power plant to break ground in nearly three decades. And with the new authority granted by the president's

46

Secretary Chu's Op-Ed on Small Modular Reactors in the Wall Street Journal  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Secretary Chu's Op-Ed on Small Modular Reactors in the Wall Street Secretary Chu's Op-Ed on Small Modular Reactors in the Wall Street Journal Secretary Chu's Op-Ed on Small Modular Reactors in the Wall Street Journal March 23, 2010 - 12:24pm Addthis Washington, D.C. - Today, the Wall Street Journal published an op-ed by U.S. Secretary of Energy Steven Chu on small modular reactors. The op-ed can be found here. The text of the op-ed is below: Small modular reactors will expand the ways we use atomic power. By Steven Chu, Secretary of Energy Wall Street Journal America is on the cusp of reviving its nuclear power industry. Last month President Obama pledged more than $8 billion in conditional loan guarantees for what will be the first U.S. nuclear power plant to break ground in nearly three decades. And with the new authority granted by the president's

47

Modularity in design of the MIT Pebble Bed Reactor  

E-Print Network (OSTI)

The future of new nuclear power plant construction will depend in large part on the ability of designers to reduce capital, operations, and maintenance costs. One of the methods proposed, is to enhance the modularity of ...

Berte, Marc Vincent, 1977-

2004-01-01T23:59:59.000Z

48

Energy Department Announces New Investment in U.S. Small Modular Reactor  

NLE Websites -- All DOE Office Websites (Extended Search)

Energy Department Announces New Investment in U.S. Small Modular Reactor Design and Commercialization Department to Issue Follow-on Solicitation on SMR Technology Innovation WASHINGTON - As part of the Obama Administration's all-of-the-above strategy to deploy every available source of American energy, the Energy Department today announced an award to support a new project to design, license and help commercialize small modular reactors (SMR) in the United States. This award follows a funding opportunity announcement in March 2012. The project supported by the award will be led by Babcock & Wilcox (B&W) in partnership with the Tennessee Valley Authority and Bechtel International. In addition, the Department announced plans to issue a follow-on solicitation open to other companies and manufacturers, focused on furthering small modular reactor efficiency, operations and design.

49

SASSI Methodology-Based Sensitivity Studies for Deeply Embedded Structures, Such As Small Modular Reactors (SMRs)  

Energy.gov (U.S. Department of Energy (DOE))

SASSI Methodology-Based Sensitivity Studies for Deeply Embedded Structures, Such As Small Modular Reactors (SMRs) Dr. Dan M. Ghiocel Ghiocel Predictive Technologies Inc. http://www.ghiocel-tech.com 2014 DOE Natural Phenomena Hazards Meeting Germantown, MD, October 21-22, 2014

50

Small Modular Reactor Report (SEAB) | Department of Energy  

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

Reactors Presentation to Secretary of Energy Advisory Board - Deputy Assistant Secretary John Kelly A Strategic Framework for SMR Deployment Meeting Materials: December 9, 2010...

51

Final report on the use of the modular-logic-nomenclature approach for the N-reactor probabilistic risk assessment  

SciTech Connect

The N-Reactor probabilistic risk assessment adaption of the modular logic approach for fault tree modeling has led to the update of the master logic diagram (MLD) nomenclature to conform with a standard modular-logic-model-nomeclature format. This report describes the MLD nomenclature system and provides a listing of the updated MLD label codes, along with the original codes.

NONE

1986-06-10T23:59:59.000Z

52

Population Sensitivity Evaluation of Two Proposed Hampton Roads Area Sites for a Possible Small Modular Reactor  

SciTech Connect

The overall objective of this research project is to use the OR-SAGE tool to support the US Department of Energy (DOE) Office of Nuclear Energy (NE) in evaluating future electrical generation deployment options for small modular reactors (SMRs) in areas with significant energy demand from the federal sector. Deployment of SMRs in zones with high federal energy use can provide a means of meeting federal clean energy goals.

Belles, R. J. [ORNL; Omitaomu, O. A. [ORNL

2014-08-01T23:59:59.000Z

53

Reference modular High Temperature Gas-Cooled Reactor Plant: Concept description report  

SciTech Connect

This report provides a summary description of the Modular High Temperature Gas-Cooled Reactor (MHTGR) concept and interim results of assessments of costs, safety, constructibility, operability, maintainability, and availability. Conceptual design of this concept was initiated in October 1985 and is scheduled for completion in 1987. Participating industrial contractors are Bechtel National, Inc. (BNI), Stone and Webster Engineering Corporation (SWEC), GA Technologies, Inc. (GA), General Electric Co. (GE), and Combustion Engineering, Inc. (C-E).

Not Available

1986-10-01T23:59:59.000Z

54

Modular high temperature gas-cooled reactor plant design duty cycle. Revision 3  

SciTech Connect

This document defines the Plant Design Duty Cycle (PCDC) for the Modular High Temperature Gas-cooled Reactor (MHTGR). The duty cycle is a set of events and their design number of occurrences over the life of the plant for which the MHTGR plant shall be designed to ensure that the plant meets all the top-level requirements. The duty cycle is representative of the types of events to be expected in multiple reactor module-turbine plant configurations of the MHTGR. A synopsis of each PDDC event is presented to provide an overview of the plant response and consequence. 8 refs., 1 fig., 4 tabs.

Chan, T.

1989-12-31T23:59:59.000Z

55

Modular Pebble-Bed Reactor Project: Laboratory-Directed Research and Development Program FY 2002 Annual Report  

SciTech Connect

This report documents the results of our research in FY-02 on pebble-bed reactor technology under our Laboratory Directed Research and Development (LDRD) project entitled the Modular Pebble-Bed Reactor. The MPBR is an advanced reactor concept that can meet the energy and environmental needs of future generations under DOEs Generation IV initiative. Our work is focused in three areas: neutronics, core design and fuel cycle; reactor safety and thermal hydraulics; and fuel performance.

Petti, David Andrew; Dolan, Thomas James; Miller, Gregory Kent; Moore, Richard Leroy; Terry, William Knox; Ougouag, Abderrafi Mohammed-El-Ami; Oh, Chang H; Gougar, Hans D

2002-11-01T23:59:59.000Z

56

Radiation Resistance of Structural Materials of Nuclear Reactors on Irradiation with High-Energy Hydrogen and Helium Ions  

Science Journals Connector (OSTI)

Basic principles of determination of the radiation resistance of structural materials of nuclear reactors with implantation of high-energy hydrogen and helium atoms have been presented. ... them with hydrogen and...

F. F. Komarov; A. F. Komarov; Vl. V. Pil?ko

2013-11-01T23:59:59.000Z

57

Small modular reactors and the future of nuclear power in the United States  

Science Journals Connector (OSTI)

Abstract Small modular reactors are the latest new technology that nuclear advocates tout as the game changer that will overcome previous economic failures of nuclear power. The debate over \\{SMRs\\} has been particularly intense because of the rapid failure of large nuclear renaissance reactors in market economies, the urgent need to address climate change, and the dramatic success of alternative, decentralized resources in lowering costs and increasing deployment. This paper assesses the prospects for SMR technology from three perspectives: the implications of the history of cost escalation in nuclear reactor construction for learning, economies of scale and other process that SMR advocates claim will lower cost; the challenges SMR technology faces in terms of high costs resulting from lost economies of scale, long lead time needed to develop a new design, the size of the task to create assembly lines for modular reactors and intense concern about safety; and the cost and other characteristics e.g. scalability, speed to market, flexibility, etc. of available alternatives compared SMR technology. The paper concludes that the decision of the major vendors (Westinghouse and B&W) to dramatically reduce SMR development efforts reflects the severe disadvantages that SMR technology faces in the next several decades.

Mark Cooper

2014-01-01T23:59:59.000Z

58

Modular Hybrid Plasma Reactor for Low Cost Bulk Production of Nanomaterials  

SciTech Connect

INL developed a bench scale modular hybrid plasma system for gas phase nanomaterials synthesis. The system was being optimized for WO3 nanoparticles production and scale model projection to a 300 kW pilot system. During the course of technology development many modifications had been done to the system to resolve technical issues that had surfaced and also to improve the performance. All project tasks had been completed except 2 optimization subtasks. These 2 subtasks, a 4-hour and an 8-hour continuous powder production runs at 1 lb/hr powder feeding rate, were unable to complete due to technical issues developed with the reactor system. The 4-hour run had been attempted twice and both times the run was terminated prematurely. The modular electrode for the plasma system was significantly redesigned to address the technical issues. Fabrication of the redesigned modular electrodes and additional components had been completed at the end of the project life. However, not enough resource was available to perform tests to evaluate the performance of the new modifications. More development work would be needed to resolve these problems prior to scaling. The technology demonstrated a surprising capability of synthesizing a single phase of meta-stable delta-Al2O3 from pure alpha-phase large Al2O3 powder. The formation of delta-Al2O3 was surprising because this phase is meta-stable and only formed between 973-1073 K, and delta-Al2O3 is very difficult to synthesize as a single phase. Besides the specific temperature window to form this phase, this meta-stable phase may have been stabilized by nanoparticle size formed in a high temperature plasma process. This technology may possess the capability to produce unusual meta-stable nanophase materials that would be otherwise difficult to produce by conventional methods. A 300 kW INL modular hybrid plasma pilot scale model reactor had been projected using the experimental data from PPG Industries 300 kW hot wall plasma reactor. The projected size of the INL 300 kW pilot model reactor would be about 15% that of the PPG 300 kW hot wall plasma reactor. Including the safety net factor the projected INL pilot reactor size would be 25-30% of the PPG 300 kW hot wall plasma pilot reactor. Due to the modularity of the INL plasma reactor and the energy cascading effect from the upstream plasma to the downstream plasma the energy utilization is more efficient in material processing. It is envisioning that the material through put range for the INL pilot reactor would be comparable to the PPG 300 kW pilot reactor but the energy consumption would be lower. The INL hybrid plasma technology is rather close to being optimized for scaling to a pilot system. More near term development work is still needed to complete the process optimization before pilot scaling.

Peter C. Kong

2011-12-01T23:59:59.000Z

59

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

SciTech Connect

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

Not Available

1983-09-01T23:59:59.000Z

60

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

SciTech Connect

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

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

2012-01-17T23:59:59.000Z

Note: This page contains sample records for the topic "modular helium reactor" 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

Development of the Mathematics of Learning Curve Models for Evaluating Small Modular Reactor Economics  

SciTech Connect

The cost of nuclear power is a straightforward yet complicated topic. It is straightforward in that the cost of nuclear power is a function of the cost to build the nuclear power plant, the cost to operate and maintain it, and the cost to provide fuel for it. It is complicated in that some of those costs are not necessarily known, introducing uncertainty into the analysis. For large light water reactor (LWR)-based nuclear power plants, the uncertainty is mainly contained within the cost of construction. The typical costs of operations and maintenance (O&M), as well as fuel, are well known based on the current fleet of LWRs. However, the last currently operating reactor to come online was Watts Bar 1 in May 1996; thus, the expected construction costs for gigawatt (GW)-class reactors in the United States are based on information nearly two decades old. Extrapolating construction, O&M, and fuel costs from GW-class LWRs to LWR-based small modular reactors (SMRs) introduces even more complication. The per-installed-kilowatt construction costs for SMRs are likely to be higher than those for the GW-class reactors based on the property of the economy of scale. Generally speaking, the economy of scale is the tendency for overall costs to increase slower than the overall production capacity. For power plants, this means that doubling the power production capacity would be expected to cost less than twice as much. Applying this property in the opposite direction, halving the power production capacity would be expected to cost more than half as much. This can potentially make the SMRs less competitive in the electricity market against the GW-class reactors, as well as against other power sources such as natural gas and subsidized renewables. One factor that can potentially aid the SMRs in achieving economic competitiveness is an economy of numbers, as opposed to the economy of scale, associated with learning curves. The basic concept of the learning curve is that the more a new process is repeated, the more efficient the process can be made. Assuming that efficiency directly relates to cost means that the more a new process is repeated successfully and efficiently, the less costly the process can be made. This factor ties directly into the factory fabrication and modularization aspect of the SMR paradigmmanufacturing serial, standardized, identical components for use in nuclear power plants can allow the SMR industry to use the learning curves to predict and optimize deployment costs.

Harrison, T. J. [ORNL

2014-02-01T23:59:59.000Z

62

Effects of Levels of Automation for Advanced Small Modular Reactors: Impacts on Performance, Workload, and Situation Awareness  

SciTech Connect

The Human-Automation Collaboration (HAC) research effort is a part of the Department of Energy (DOE) sponsored Advanced Small Modular Reactor (AdvSMR) program conducted at Idaho National Laboratory (INL). The DOE AdvSMR program focuses on plant design and management, reduction of capital costs as well as plant operations and maintenance costs (O&M), and factory production costs benefits.

Johanna Oxstrand; Katya Le Blanc

2014-07-01T23:59:59.000Z

63

A Framework to Expand and Advance Probabilistic Risk Assessment to Support Small Modular Reactors  

SciTech Connect

During the early development of nuclear power plants, researchers and engineers focused on many aspects of plant operation, two of which were getting the newly-found technology to work and minimizing the likelihood of perceived accidents through redundancy and diversity. As time, and our experience, has progressed, the realization of plant operational risk/reliability has entered into the design, operation, and regulation of these plants. But, to date, we have only dabbled at the surface of risk and reliability technologies. For the next generation of small modular reactors (SMRs), it is imperative that these technologies evolve into an accepted, encompassing, validated, and integral part of the plant in order to reduce costs and to demonstrate safe operation. Further, while it is presumed that safety margins are substantial for proposed SMR designs, the depiction and demonstration of these margins needs to be better understood in order to optimize the licensing process.

Curtis Smith; David Schwieder; Robert Nourgaliev; Cherie Phelan; Diego Mandelli; Kellie Kvarfordt; Robert Youngblood

2012-09-01T23:59:59.000Z

64

Advanced Small Modular Reactor (SMR) Probabilistic Risk Assessment (PRA) Technical Exchange Meeting  

SciTech Connect

During FY13, the INL developed an advanced SMR PRA framework which has been described in the report Small Modular Reactor (SMR) Probabilistic Risk Assessment (PRA) Detailed Technical Framework Specification, INL/EXT-13-28974 (April 2013). In this framework, the various areas are considered: Probabilistic models to provide information specific to advanced SMRs Representation of specific SMR design issues such as having co-located modules and passive safety features Use of modern open-source and readily available analysis methods Internal and external events resulting in impacts to safety All-hazards considerations Methods to support the identification of design vulnerabilities Mechanistic and probabilistic data needs to support modeling and tools In order to describe this framework more fully and obtain feedback on the proposed approaches, the INL hosted a technical exchange meeting during August 2013. This report describes the outcomes of that meeting.

Curtis Smith

2013-09-01T23:59:59.000Z

65

Westinghouse Small Modular Reactor balance of plant and supporting systems design  

SciTech Connect

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

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

2012-07-01T23:59:59.000Z

66

Small Modular Reactor: First of a Kind (FOAK) and Nth of a Kind (NOAK) Economic Analysis  

SciTech Connect

Small modular reactors (SMRs) refer to any reactor design in which the electricity generated is less than 300 MWe. Often medium sized reactors with power less than 700 MWe are also grouped into this category. Internationally, the development of a variety of designs for SMRs is booming with many designs approaching maturity and even in or nearing the licensing stage. It is for this reason that a generalized yet comprehensive economic model for first of a kind (FOAK) through nth of a kind (NOAK) SMRs based upon rated power, plant configuration, and the fiscal environment was developed. In the model, a particular projects feasibility is assessed with regards to market conditions and by commonly utilized capital budgeting techniques, such as the net present value (NPV), internal rate of return (IRR), Payback, and more importantly, the levelized cost of energy (LCOE) for comparison to other energy production technologies. Finally, a sensitivity analysis was performed to determine the effects of changing debt, equity, interest rate, and conditions on the LCOE. The economic model is primarily applied to the near future water cooled SMR designs in the United States. Other gas cooled and liquid metal cooled SMR designs have been briefly outlined in terms of how the economic model would change. FOAK and NOAK SMR costs were determined for a site containing seven 180 MWe water cooled SMRs and compared to a site containing one 1260 MWe reactor. With an equal share of debt and equity and a 10% cost of debt and equity, the LCOE was determined to be $79 $84/MWh and $80/MWh for the SMR and large reactor sites, respectively. With a cost of equity of 15%, the SMR LCOE increased substantially to $103 $109/MWh. Finally, an increase in the equity share to 70% at the 15% cost of equity resulted in an even higher LCOE, demonstrating the large variation in results due to financial and market factors. The NPV and IRR both decreased with increasing LCOE. Unless the price of electricity increases along with the LCOE, the projects may become unprofitable. This is the case at the LCOE of $103 $109/MW, in which the NPV became negative. The IRR increased with increasing electricity price. Three cases, electric only base, storagecompressed air energy storage or pumped hydro, and hydrogen production, were performed incorporating SMRs into a nuclear wind natural gas hybrid energy system for the New York West Central region. The operational costs for three cases were calculated as $27/MWh, $25/MWh, and $28/MWh, respectively. A 3% increase in profits was demonstrated for the storage case over the electric only base case.

Lauren M. Boldon; Piyush Sabharwall

2014-08-01T23:59:59.000Z

67

Representative Source Terms and the Influence of Reactor Attributes on Functional Containment in Modular High-Temperature Gas-Cooled Reactors  

SciTech Connect

Modular high-temperature gas-cooled reactors (MHTGRs) offer a high degree of passive safety. The low power density of the reactor and the high heat capacity of the graphite core result in slow transients that do not challenge the integrity of the robust TRISO fuel. Another benefit of this fuel form and the surrounding graphite is their superior ability to retain fission products under all anticipated normal and off-normal conditions, which limits reactor accident source terms to very low values. In this paper, we develop estimates of the source term for a generic MHTGR to illustrate the performance of the radionuclide barriers that comprise the MHTGR functional containment. We also examine the influence of initial fuel quality, fuel performance/failure, reactor outlet temperature, and retention outside of the reactor core on the resultant source term to the environment.

D. A. Petti; Hans Gougar; Dick Hobbins; Pete Lowry

2013-11-01T23:59:59.000Z

68

High-temperature gas-cooled reactor helium compatibility studies: results of 10,000-hour exposure of selected alloys in simulated reactor helium  

SciTech Connect

Work on the HTGR Helium Compatibility Task accomplished during the period March 31, 1977 through September 30, 1979, is documented in this report. Emphasis is on the results and analyses of creep data to 10,000 h and the detailed metallurgical evaluations performed on candidate alloy specimens tested for up to 10,000 h. Long-term creep and unstressed aging data in controlled-impurity helium and in air at 800, 900, and 1000/sup 0/C are reported for alloys included in the program in FY-76, including the wrought solid-solution-strengthened alloys, Hastelloy X, Hastelloy S, RA 333, and HD 556, and the centrifugally cast austenitic alloys, HK 40, Supertherm, Manaurite 36X, Manaurite 36XS, and Manaurite 900.

Lechtenberg, T.A.; Stevenson, R.D.; Johnson, W.R.

1980-05-01T23:59:59.000Z

69

Modular High-Temperature Gas-Cooled Reactor short term thermal response to flow and reactivity transients  

SciTech Connect

The analyses reported here have been conducted at the Oak Ridge National Laboratory (ORNL) for the US Nuclear Regulatory Commission's (NRC's) Division of Regulatory Applications of the Office of Nuclear Regulatory Research. The short-term thermal response of the Modular High-Temperature Gas-Cooled Reactor (MHTGR) is analyzed for a range of flow and reactivity transients. These include loss of forced circulation (LOFC) without scram, moisture ingress, spurious withdrawal of a control rod group, hypothetical large and rapid positive reactivity insertion, and a rapid core cooling event. The coupled heat transfer-neutron kinetics model is also described.

Cleveland, J.C.

1988-01-01T23:59:59.000Z

70

INITIATORS AND TRIGGERING CONDITIONS FOR ADAPTIVE AUTOMATION IN ADVANCED SMALL MODULAR REACTORS  

SciTech Connect

It is anticipated that Advanced Small Modular Reactors (AdvSMRs) will employ high degrees of automation. High levels of automation can enhance system performance, but often at the cost of reduced human performance. Automation can lead to human out-of the loop issues, unbalanced workload, complacency, and other problems if it is not designed properly. Researchers have proposed adaptive automation (defined as dynamic or flexible allocation of functions) as a way to get the benefits of higher levels of automation without the human performance costs. Adaptive automation has the potential to balance operator workload and enhance operator situation awareness by allocating functions to the operators in a way that is sensitive to overall workload and capabilities at the time of operation. However, there still a number of questions regarding how to effectively design adaptive automation to achieve that potential. One of those questions is related to how to initiate (or trigger) a shift in automation in order to provide maximal sensitivity to operator needs without introducing undesirable consequences (such as unpredictable mode changes). Several triggering mechanisms for shifts in adaptive automation have been proposed including: operator initiated, critical events, performance-based, physiological measurement, model-based, and hybrid methods. As part of a larger project to develop design guidance for human-automation collaboration in AdvSMRs, researchers at Idaho National Laboratory have investigated the effectiveness and applicability of each of these triggering mechanisms in the context of AdvSMR. Researchers reviewed the empirical literature on adaptive automation and assessed each triggering mechanism based on the human-system performance consequences of employing that mechanism. Researchers also assessed the practicality and feasibility of using the mechanism in the context of an AdvSMR control room. Results indicate that there are tradeoffs associated with each mechanism, but that some are more applicable to the AdvSMR domain. The two mechanisms that consistently improve performance in laboratory studies are operator initiated adaptive automation based on hierarchical task delegation and the Electroencephalogram(EEG) based measure of engagement. Current EEG methods are intrusive and require intensive analysis; therefore it is not recommended for an AdvSMR control rooms at this time. Researchers also discuss limitations in the existing empirical literature and make recommendations for further research.

Katya L Le Blanc; Johanna h Oxstrand

2014-04-01T23:59:59.000Z

71

Deep Burn: Development of Transuranic Fuel for High-Temperature Helium-Cooled Reactors- Monthly Highlights September 2010  

SciTech Connect

The DB Program monthly highlights report for August 2010, ORNL/TM-2010/184, was distributed to program participants by email on September 17. This report discusses: (1) Core and Fuel Analysis - (a) Core Design Optimization in the HTR (high temperature helium-cooled reactor) Prismatic Design (Logos), (b) Core Design Optimization in the HTR Pebble Bed Design (INL), (c) Microfuel analysis for the DB HTR (INL, GA, Logos); (2) Spent Fuel Management - (a) TRISO (tri-structural isotropic) repository behavior (UNLV), (b) Repository performance of TRISO fuel (UCB); (3) Fuel Cycle Integration of the HTR (high temperature helium-cooled reactor) - Synergy with other reactor fuel cycles (GA, Logos); (4) TRU (transuranic elements) HTR Fuel Qualification - (a) Thermochemical Modeling, (b) Actinide and Fission Product Transport, (c) Radiation Damage and Properties; (5) HTR Spent Fuel Recycle - (a) TRU Kernel Development (ORNL), (b) Coating Development (ORNL), (c) Characterization Development and Support, (d) ZrC Properties and Handbook; and (6) HTR Fuel Recycle - (a) Graphite Recycle (ORNL), (b) Aqueous Reprocessing, (c) Pyrochemical Reprocessing METROX (metal recovery from oxide fuel) Process Development (ANL).

Snead, Lance Lewis [ORNL; Besmann, Theodore M [ORNL; Collins, Emory D [ORNL; Bell, Gary L [ORNL

2010-10-01T23:59:59.000Z

72

MORECA: A computer code for simulating modular high-temperature gas-cooled reactor core heatup accidents  

SciTech Connect

The design features of the modular high-temperature gas-cooled reactor (MHTGR) have the potential to make it essentially invulnerable to damage from postulated core heatup accidents. This report describes the ORNL MORECA code, which was developed for analyzing postulated long-term core heatup scenarios for which active cooling systems used to remove afterheat following the accidents can be assumed to the unavailable. Simulations of long-term loss-of-forced-convection accidents, both with and without depressurization of the primary coolant, have shown that maximum core temperatures stay below the point at which any significant fuel failures and fission product releases are expected. Sensitivity studies also have been done to determine the effects of errors in the predictions due both to uncertainties in the modeling and to the assumptions about operational parameters. MORECA models the US Department of Energy reference design of a standard MHTGR.

Ball, S.J. (Oak Ridge National Lab., TN (United States))

1991-10-01T23:59:59.000Z

73

Mechanical characterization of metallic materials for high-temperature gas-cooled reactors in air and in helium environments  

SciTech Connect

In the French R and D program for high-temperature gas-cooled reactors (HTGRs), three metallic alloys were studied: steel Chromesco-3 with 2.25% chromium, alloy 800H, and Hastelloy-X. The Chromesco-3 and alloy 800H creep behavior is the same in air and in HTGR atmosphere (helium). The tensile tests of Hastelloy-X specimens reveal that aging has embrittlement and hardening effects up to 700/sup 0/C, but the creep tests at 800/sup 0/C show opposite effects. This particular behavior could be due to induced precipitation by aging and the depletion of hardening elements from the matrix. Tests show a low influence of cobalt content on mechanical properties of Hastelloy-X.

Sainfort, G.; Cappelaere, M.; Gregoire, J.; Sannier, J.

1984-07-01T23:59:59.000Z

74

Expert assessments of the cost of light water small modular reactors  

Science Journals Connector (OSTI)

...Schrattenholzer (S1) report learning...include technical progress economies...suggests, the result we report are probably...high temperature gas cooled reactor...adapted from the report in question (29...storage systems 3) Turbine plant equipmentHigh...

Ahmed Abdulla; Ins Lima Azevedo; M. Granger Morgan

2013-01-01T23:59:59.000Z

75

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

SciTech Connect

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

Crosswait, K.M.

1994-04-01T23:59:59.000Z

76

Thermalization and Exhaust of Helium in a Future Thermonuclear Reactor: Partly an Atomic Physics Problem  

Science Journals Connector (OSTI)

The magnetically confined plasma of a continuously or quasi-continuously working thermonuclear fusion reactor must satisfy several severe conditions in ... the a-particles born in the D-T fusion process, the othe...

H. W. Drawin

1980-01-01T23:59:59.000Z

77

Design modification for the modular helium reactor for higher temperature operation and reliability studies for nuclear hydrogen production processes  

E-Print Network (OSTI)

of these modifications together, the PVT is reduced to ~350 0C while keeping the outlet temperature at 950 0C and maintaining the PFT within acceptable limits. The vessel and fuel temperatures during low pressure conduction cooldown and high pressure conduction cooldown...

Reza, S.M. Mohsin

2009-05-15T23:59:59.000Z

78

The passive safety characteristics of modular high temperature gas-cooled reactor fuel elements  

SciTech Connect

High-Temperature Gas-Cooled Reactors (HTGR) in both the US and West Germany use an all-ceramic, coated fuel particle to retain fission products. Data from irradiation, postirradiation examinations and postirradiation heating experiments are used to study the performance capabilities of the fuel particles. The experimental results from fission product release tests with HTGR fuel are discussed. These data are used for development of predictive fuel performance models for purposes of design, licensing, and risk analyses. During off normal events, where temperatures may reach up to 1600/degree/C, the data show that no significant radionuclide releases from the fuel will occur.

Goodin, D.T.; Kania, M.J.; Nabielek, H.; Schenk, W.; Verfondern, K.

1988-01-01T23:59:59.000Z

79

Technical Needs for Prototypic Prognostic Technique Demonstration for Advanced Small Modular Reactor Passive Components  

SciTech Connect

This report identifies a number of requirements for prognostics health management of passive systems in AdvSMRs, documents technical gaps in establishing a prototypical prognostic methodology for this purpose, and describes a preliminary research plan for addressing these technical gaps. AdvSMRs span multiple concepts; therefore a technology- and design-neutral approach is taken, with the focus being on characteristics that are likely to be common to all or several AdvSMR concepts. An evaluation of available literature is used to identify proposed concepts for AdvSMRs along with likely operational characteristics. Available operating experience of advanced reactors is used in identifying passive components that may be subject to degradation, materials likely to be used for these components, and potential modes of degradation of these components. This information helps in assessing measurement needs for PHM systems, as well as defining functional requirements of PHM systems. An assessment of current state-of-the-art approaches to measurements, sensors and instrumentation, diagnostics and prognostics is also documented. This state-of-the-art evaluation, combined with the requirements, may be used to identify technical gaps and research needs in the development, evaluation, and deployment of PHM systems for AdvSMRs. A preliminary research plan to address high-priority research needs for the deployment of PHM systems to AdvSMRs is described, with the objective being the demonstration of prototypic prognostics technology for passive components in AdvSMRs. Greater efficiency in achieving this objective can be gained through judicious selection of materials and degradation modes that are relevant to proposed AdvSMR concepts, and for which significant knowledge already exists. These selections were made based on multiple constraints including the analysis performed in this document, ready access to laboratory-scale facilities for materials testing and measurement, and potential synergies with other national laboratory and university partners.

Meyer, Ryan M.; Coble, Jamie B.; Hirt, Evelyn H.; Ramuhalli, Pradeep; Mitchell, Mark R.; Wootan, David W.; Berglin, Eric J.; Bond, Leonard J.; Henager, Charles H.

2013-05-17T23:59:59.000Z

80

A future for nuclear energy: pebble bed reactors  

Science Journals Connector (OSTI)

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

Andrew C. Kadak

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modular helium reactor" 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

Discussion Paper for DOE SEAB/SMR Subcommittee V.H. Reis Small Modular Reactors and U.S. Clean Energy Sources for Electricity  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Discussion Paper for DOE SEAB/SMR Subcommittee Discussion Paper for DOE SEAB/SMR Subcommittee V.H. Reis Small Modular Reactors and U.S. Clean Energy Sources for Electricity In his 2011 State of the Union speech President Obama stated: "By 2035, 80 percent of America's electricity will come from clean energy sources." As yet, there is no official definition of a clean energy source, but a sensible definition is to suggest a "clean energy standard" where sources are weighted with respect to how much CO 2 they emit per unit of electrical energy produced. That is: Where F CE = Fraction of electricity for clean energy sources (multiply by 100 to get percent)

82

U.S. Department Of Energy Advanced Small Modular Reactor R&D Program: Instrumentation, Controls, and Human-Machine Interface (ICHMI) Pathway  

SciTech Connect

Instrumentation, controls, and human-machine interfaces (ICHMI) are essential enabling technologies that strongly influence nuclear power plant performance and operational costs. The nuclear power industry is currently engaged in a transition from traditional analog-based instrumentation, controls, and human-machine interface systems to implementations employing digital technologies. This transition has primarily occurred in an ad hoc fashion through individual system upgrades at existing plants and has been constrained by licenseability concerns. Although the recent progress in constructing new plants has spurred design of more fully digital plant-wide ICHMI systems, the experience base in the nuclear power application domain is limited. Additionally, development of advanced reactor concepts, such as Generation IV designs and small modular reactors, introduces different plant conditions (e.g., higher temperatures, different coolants, etc.) and unique plant configurations (e.g., multiunit plants with shared systems, balance of plant architectures with reconfigurable co-generation options) that increase the need for enhanced ICHMI capabilities to fully achieve industry goals related to economic competitiveness, safety and reliability, sustainability, and proliferation resistance and physical protection. As a result, significant challenges remain to be addressed to enable the nuclear power industry to complete the transition to safe and comprehensive use of modern ICHMI technology. The U.S. Department of Energy (DOE) has recognized that ICHMI research, development, and demonstration (RD&D) is needed to resolve the technical challenges that may compromise the effective and efficient utilization of modern ICHMI technology and consequently inhibit realization of the benefits offered by expanded utilization of nuclear power. Consequently, several DOE programs have substantial ICHMI RD&D elements within their respective research portfolios. This paper describes current ICHMI research in support of advanced small modular reactors. The objectives that can be achieved through execution of the defined RD&D are to provide optimal technical solutions to critical ICHMI issues, resolve technology gaps arising from the unique measurement and control characteristics of advanced reactor concepts, provide demonstration of needed technologies and methodologies in the nuclear power application domain, mature emerging technologies to facilitate commercialization, and establish necessary technical evidence and application experience to enable timely and predictable licensing. 1 Introduction Instrumentation, controls, and human-machine interfaces are essential enabling technologies that strongly influence nuclear power plant performance and operational costs. The nuclear power industry is currently engaged in a transition from traditional analog-based instrumentation, controls, and human-machine interface (ICHMI) systems to implementations employing digital technologies. This transition has primarily occurred in an ad hoc fashion through individual system upgrades at existing plants and has been constrained by licenseability concerns. Although the recent progress in constructing new plants has spurred design of more fully digital plant-wide ICHMI systems, the experience base in the nuclear power application domain is limited. Additionally, development of advanced reactor concepts, such as Generation IV designs and small modular reactors, introduces different plant conditions (e.g., higher temperatures, different coolants, etc.) and unique plant configurations (e.g., multiunit plants with shared systems, balance of plant architectures with reconfigurable co-generation options) that increase the need for enhanced ICHMI capabilities to fully achieve industry goals related to economic competitiveness, safety and reliability, sustainability, and proliferation resistance and physical protection. As a result, significant challenges remain to be addressed to enable the nuclear power industry to complete the transition to safe and comprehensive use of m

Holcomb, David Eugene [ORNL; Wood, Richard Thomas [ORNL

2013-01-01T23:59:59.000Z

83

Innovative safety features of the modular HTGR  

SciTech Connect

The Modular High Temperature Gas-Cooled Reactor (MHTGR) is an advanced reactor concept under development through a cooperative program involving the US Government, the nuclear industry, and the utilities. Near-term development is focused on electricity generation. The top-level safety requirement is that the plant's operation not disturb the normal day-to-day activities of the public. Quantitatively, this requires that the design meet the US Environmental Protection Agency's Protective Action Guides at the site boundary and hence preclude the need for sheltering or evacuation of the public. To meet these stringent safety requirements and at the same time provide a cost competitive design requires the innovative use of the basic high temperature gas-cooled reactor features of ceramic fuel, helium coolant, and a graphite moderator. The specific fuel composition and core size and configuration have been selected to the use the natural characteristics of these materials to develop significantly higher margins of safety. In this document the innovative safety features of the MHTGR are reviewed by examining the safety response to events challenging the functions relied on to retain radionuclides within the coated fuel particles. A broad range of challenges to core heat removal are examined, including a loss of helium pressure of a simultaneous loss of forced cooling of the core. The challenges to control of heat generation consider not only the failure to insert the reactivity control systems but also the withdrawal of control rods. Finally, challenges to control of chemical attack of the ceramic-coated fuel are considered, including catastrophic failure of the steam generator, which allows water ingress, or failure of the pressure vessels, which allows air ingress. The plant's response to these extreme challenges is not dependent on operator action, and the events considered encompass conceivable operator errors.

Silady, F.A.; Simon, W.A.

1992-01-01T23:59:59.000Z

84

Innovative safety features of the modular HTGR  

SciTech Connect

The Modular High Temperature Gas-Cooled Reactor (MHTGR) is an advanced reactor concept under development through a cooperative program involving the US Government, the nuclear industry, and the utilities. Near-term development is focused on electricity generation. The top-level safety requirement is that the plant`s operation not disturb the normal day-to-day activities of the public. Quantitatively, this requires that the design meet the US Environmental Protection Agency`s Protective Action Guides at the site boundary and hence preclude the need for sheltering or evacuation of the public. To meet these stringent safety requirements and at the same time provide a cost competitive design requires the innovative use of the basic high temperature gas-cooled reactor features of ceramic fuel, helium coolant, and a graphite moderator. The specific fuel composition and core size and configuration have been selected to the use the natural characteristics of these materials to develop significantly higher margins of safety. In this document the innovative safety features of the MHTGR are reviewed by examining the safety response to events challenging the functions relied on to retain radionuclides within the coated fuel particles. A broad range of challenges to core heat removal are examined, including a loss of helium pressure of a simultaneous loss of forced cooling of the core. The challenges to control of heat generation consider not only the failure to insert the reactivity control systems but also the withdrawal of control rods. Finally, challenges to control of chemical attack of the ceramic-coated fuel are considered, including catastrophic failure of the steam generator, which allows water ingress, or failure of the pressure vessels, which allows air ingress. The plant`s response to these extreme challenges is not dependent on operator action, and the events considered encompass conceivable operator errors.

Silady, F.A.; Simon, W.A.

1992-01-01T23:59:59.000Z

85

Modular thermoacoustic refrigerator  

Science Journals Connector (OSTI)

A thermoacousticrefrigerator was built to explore scaling to large heat flux. The refrigerator was constructed according to a modular design so that various stack heat exchanger and resonator sections are easily interchangeable. The resonator is driven by a commercial 10?in. woofer. Initial tests using pure helium gas as the working fluid and steel honeycomb (0.8?mm cell) for the stack pumped 60 W of heat against a 10?C temperature gradient. Measurements of heat flux and efficiency will be reported as functions of stack structure (e.g. pore size and shape) and will be compared with theoretical predictions.

Steven R. Murrell; George Mozurkewich

1993-01-01T23:59:59.000Z

86

Symmetric modular torsatron  

DOE Patents (OSTI)

A fusion reactor device is provided in which the magnetic fields for plasma confinement in a toroidal configuration is produced by a plurality of symmetrical modular coils arranged to form a symmetric modular torsatron referred to as a symmotron. Each of the identical modular coils is helically deformed and comprise one field period of the torsatron. Helical segments of each coil are connected by means of toroidally directed windbacks which may also provide part of the vertical field required for positioning the plasma. The stray fields of the windback segments may be compensated by toroidal coils. A variety of magnetic confinement flux surface configurations may be produced by proper modulation of the winding pitch of the helical segments of the coils, as in a conventional torsatron, winding the helix on a noncircular cross section and varying the poloidal and radial location of the windbacks and the compensating toroidal ring coils.

Rome, J.A.; Harris, J.H.

1984-01-01T23:59:59.000Z

87

Modularity Approach Modular Pebble Bed Reactor (MPBR)  

E-Print Network (OSTI)

°C 126.7kg/s Circulator HPT 52.8MW Precooler Inventory control Bypass Valve Intercooler IHX Hatch Equip Access Hatch Equip Access Hatch Oil Refinery Hydrogen Production Desalinization Plant VHTR

88

Role of Nuclear Grade Graphite in Oxidation in Modular HTGRs  

SciTech Connect

The passively safe High Temperature Gas-cooled Reactor (HTGR) design is one of the primary concepts considered for Generation IV and Small Modular Reactor (SMR) programs. The helium cooled, nuclear grade graphite moderated core achieves extremely high operating temperatures allowing either industrial process heat or electricity generation at high efficiencies. In addition to their neutron moderating properties, nuclear grade graphite core components provide excellent high temperature stability, thermal conductivity, and chemical compatibility with the high temperature nuclear fuel form. Graphite has been continuously used in nuclear reactors since the 1940s and has performed remarkably well over a wide range of core environments and operating conditions. Graphite moderated, gas-cooled reactor designs have been safely used for research and power production purposes in multiple countries since the inception of nuclear energy development. However, graphite is a carbonaceous material, and this has generated a persistent concern that the graphite components could actually burn during either normal or accident conditions [ , ]. The common assumption is that graphite, since it is ostensibly similar to charcoal and coal, will burn in a similar manner. While charcoal and coal may have the appearance of graphite, the internal microstructure and impurities within these carbonaceous materials are very different. Volatile species and trapped moisture provide a source of oxygen within coal and charcoal allowing them to burn. The fabrication process used to produce nuclear grade graphite eliminates these oxidation enhancing impurities, creating a dense, highly ordered form of carbon possessing high thermal diffusivity and strongly (covalently) bonded atoms.

Willaim Windes; G. Strydom; J. Kane; R. Smith

2014-11-01T23:59:59.000Z

89

Carbon free energy development and the role of small modular reactors: A review and decision framework for deployment in developing countries  

Science Journals Connector (OSTI)

Abstract Global energy demand is projected to continue to grow over the next two decades, especially in developing economies. An emerging energy technology with distinct advantages for growing economies is small modular nuclear reactors (SMRs). Their smaller size makes them suitable for areas with limited grid capacities and dispersed populations while enabling flexibility in generating capacity and fuel sources. They have the ability to pair well with renewable energy sources, the major source of increased energy capacity for many developing economies. Further advantages include their passive safety features, lower capital requirements, and reduced construction times. As a result, \\{SMRs\\} have potential for overcoming energy poverty issues for growing economies without increasing carbon emissions. This study reviews the features and viability of \\{SMRs\\} to meet increasing energy capacity needs and develops a decision support framework to evaluate the market conditions for SMR deployment to emerging economies. The focus is on identifying countries best suited for domestic deployment of \\{SMRs\\} rather than vendor countries with ongoing or future SMR development programs for export. We begin by examining the characteristics of over two hundred countries and identifying those that satisfy several necessary economic, electrical grid capacity, and nuclear security conditions. Countries satisfying these necessary conditions are then evaluated using the Analytical Hierarchy Process (AHP) using criteria related to the economic and financial conditions, infrastructure and technological framework, and governmental policies within each country. The results find that countries with increasing GDP and energy demand that possess a robust infrastructure, energy production from high GHG sources, and governmental policies favorable to foreign investment are well-suited for future SMR deployment.

Geoffrey Black; Meredith A. Taylor Black; David Solan; David Shropshire

2015-01-01T23:59:59.000Z

90

A Multi-Modular Neutronically Coupled Power Generation System  

E-Print Network (OSTI)

The High Temperature Integrated Multi-Modular Thermal Reactor is a small modular reactor that uses an enhanced conductivity BeO-UO2 fuel with supercritical CO2 coolant to drive turbo-machinery in a direct Brayton cycle. The core consists of several...

Patel, Vishal

2012-07-16T23:59:59.000Z

91

Energy Department Announces New Investment in Innovative Small Modular  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Announces New Investment in Innovative Small Announces New Investment in Innovative Small Modular Reactor Energy Department Announces New Investment in Innovative Small Modular Reactor December 12, 2013 - 4:04pm Addthis NEWS MEDIA CONTACT (202) 586-4940 WASHINGTON - Building on President Obama's Climate Action Plan to continue America's leadership in clean energy innovation, the Energy Department today announced an award to NuScale Power LLC to support a new project to design, certify and help commercialize innovative small modular reactors (SMRs) in the United States. This award follows a funding opportunity announcement in March 2013. View a new Energy Department infographic on small modular reactors and their potential to provide clean, safe and cost-effective nuclear energy. "Small modular reactors represent a new generation of safe, reliable,

92

Closed cycle liquid helium refrigerators  

Science Journals Connector (OSTI)

We have developed closed cycle liquid helium refrigerators using a Joule Thomson circuit precooled by commercially available two staged Gifford Mac Mahon cryocoolers. The Joule Thomson counterflow heat exchangers are modular and have been thermo-hydraulically characterized. Fully automatic cool down and operation are achieved by two pneumatically driven by pass and expansion valves. Several apparatus have been built or are under assembly with cooling power ranging from 100 mW up to 5 Watt, for temperature ranging from 2.8 K up to 4.5 K. A trouble free operation with several warm up and cool down cycles has been proven over 7000 hours.

G. Claudet; R. Lagnier; A. Ravex

1992-01-01T23:59:59.000Z

93

Modular robot  

DOE Patents (OSTI)

A modular robot may comprise a main body having a structure defined by a plurality of stackable modules. The stackable modules may comprise a manifold, a valve module, and a control module. The manifold may comprise a top surface and a bottom surface having a plurality of fluid passages contained therein, at least one of the plurality of fluid passages terminating in a valve port located on the bottom surface of the manifold. The valve module is removably connected to the manifold and selectively fluidically connects the plurality of fluid passages contained in the manifold to a supply of pressurized fluid and to a vent. The control module is removably connected to the valve module and actuates the valve module to selectively control a flow of pressurized fluid through different ones of the plurality of fluid passages in the manifold. The manifold, valve module, and control module are mounted together in a sandwich-like manner and comprise a main body. A plurality of leg assemblies are removably connected to the main body and are removably fluidically connected to the fluid passages in the manifold so that each of the leg assemblies can be selectively actuated by the flow of pressurized fluid in different ones of the plurality of fluid passages in the manifold.

Ferrante, Todd A. (Idaho Falls, ID)

1997-01-01T23:59:59.000Z

94

Modular robot  

DOE Patents (OSTI)

A modular robot may comprise a main body having a structure defined by a plurality of stackable modules. The stackable modules may comprise a manifold, a valve module, and a control module. The manifold may comprise a top surface and a bottom surface having a plurality of fluid passages contained therein, at least one of the plurality of fluid passages terminating in a valve port located on the bottom surface of the manifold. The valve module is removably connected to the manifold and selectively fluidically connects the plurality of fluid passages contained in the manifold to a supply of pressurized fluid and to a vent. The control module is removably connected to the valve module and actuates the valve module to selectively control a flow of pressurized fluid through different ones of the plurality of fluid passages in the manifold. The manifold, valve module, and control module are mounted together in a sandwich-like manner and comprise a main body. A plurality of leg assemblies are removably connected to the main body and are removably fluidically connected to the fluid passages in the manifold so that each of the leg assemblies can be selectively actuated by the flow of pressurized fluid in different ones of the plurality of fluid passages in the manifold. 12 figs.

Ferrante, T.A.

1997-11-11T23:59:59.000Z

95

Analysis of granular flow in a pebble-bed nuclear reactor Chris H. Rycroft,1  

E-Print Network (OSTI)

-temperature reactor 2 , which offers meltdown-proof passive safety, convenient long-term waste storage, modular

Bazant, Martin Z.

96

Performance Assessment of a Recuperative Helium Gas Turbine System  

Science Journals Connector (OSTI)

Helium is considered an ideal working fluid for closed cycle gas turbines powered by the heat of nuclear reactors or solar concentrators. Energetic and exergetic based thermodynamic analyses ... applied to an act...

Rami Salah El-Emam; Ibrahim Dincer

2014-01-01T23:59:59.000Z

97

Investigation of Countercurrent Helium-Air Flows in Air-ingress Accidents for VHTRs  

SciTech Connect

The primary objective of this research is to develop an extensive experimental database for the air- ingress phenomenon for the validation of computational fluid dynamics (CFD) analyses. This research is intended to be a separate-effects experimental study. However, the project team will perform a careful scaling analysis prior to designing a scaled-down test facility in order to closely tie this research with the real application. As a reference design in this study, the team will use the 600 MWth gas turbine modular helium reactor (GT-MHR) developed by General Atomic. In the test matrix of the experiments, researchers will vary the temperature and pressure of the helium along with break size, location, shape, and orientationto simulate deferent scenarios and to identify potential mitigation strategies. Under support of the Department of Energy, a high-temperature helium test facility has been designed and is currently being constructed at Ohio State University, primarily for high- temperature compact heat exchanger testing for the VHTR program. Once the facility is in operation (expected April 2009), this study will utilize high-temperature helium up to 900C and 3 MPa for loss-of-coolant accident (LOCA) depressurization and air-ingress experiments. The project team will first conduct a scaling study and then design an air-ingress test facility. The major parameter to be measured in the experiments is oxygen (or nitrogen) concentration history at various locations following a LOCA scenario. The team will use two measurement techniques: 1) oxygen (or similar type) sensors employed in the flow field, which will introduce some undesirable intrusiveness, disturbing the flow, and 2) a planar laser-induced fluorescence (PLIF) imaging technique, which has no physical intrusiveness to the flow but requires a transparent window or test section that the laser beam can penetrate. The team will construct two test facilities, one for high-temperature helium tests with local sensors and the other for low- temperature helium tests with the PLIF technique. The results from the two instruments will provide a means to cross-calibrate the measurement techniques.

Sun, Xiaodong; Christensen, Richard; Oh, Chang

2013-10-03T23:59:59.000Z

98

Neutron-induced helium implantation in GCFR cladding  

SciTech Connect

The neutron-induced implantation of helium atoms on the exterior surfaces of the cladding of a prototypic gas-cooled fast reactor (GCFR) has been investigated analytically. A flux of recoil helium particles as high as 4.2 x 10/sup 10/ He/cm/sup 2/.s at the cladding surface has been calculated at the peak power location in the core of a 300-MWe GCFR. The calculated profile of the helium implantation rates indicates that although some helium is implanted as deep as 20 ..mu..m, more than 99% of helium particles are implanted in the first 2-..mu..m-deep layer below the cladding surface. Therefore, the implanted helium particles should mainly affect surface properties of the GCFR cladding.

Yamada, H.; Poeppel, R. B.; Sevy, R. H.

1980-10-01T23:59:59.000Z

99

ThermalHydraulic Analysis and Optimization of HCPB Breeder Unit for Future Fusion Reactor  

Science Journals Connector (OSTI)

China has proposed several concepts of breeder blanket for future fusion reactor, one of which is the helium-cooled...

Songsong Qi; Guodong Wang; Changqi Chen; Hongjun Tang

2014-09-01T23:59:59.000Z

100

Modular Integrated Energy Systems  

E-Print Network (OSTI)

Honeywell #12;Modular Integrated Energy Systems Task 5 Prototype Development Reference Design DocumentationModular Integrated Energy Systems Prepared for: Oak Ridge National Laboratory P.O. Box 2008 Building 3147 Oak Ridge, TN 37831 April 27, 2006 Prepared by: Honeywell Laboratories 3660 Technology Drive

Oak Ridge National Laboratory

Note: This page contains sample records for the topic "modular helium reactor" 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

Modular Integrated Energy Systems  

E-Print Network (OSTI)

-driven absorption chiller, · Install and monitor the performance of a prototype IES modular system employing consists of a gas turbine-generator, a heat recovery steam generator, and a waste heat fired absorption chiller. The key goals of the project are: · Develop a set of "reference" CAD-based IES modular system

Oak Ridge National Laboratory

102

Steam generator conceptual design for the modular HTGR - Dissimilar metal weld considerations  

SciTech Connect

The steam generator for the current Modular High Temperature Gas-Cooled Reactor (MHTGR) has evolved from a technology basis developed in U.S. and European gas-cooled reactor programs. The MHTGR steam generator is a vertically-oriented, counterflow, shell-and-tube, once-through, non-reheat, helical heat exchanger with helium on the shell side and water/steam in the tubes. In the MHTGR applications, the normal operating temperatures of the steam generator tubes can be as high as 638/sup 0/C (1180/sup 0/F). Concerns such as cost, creep strength, steam side scaling and stress corrosion cracking often lead to a design decision to use two different tube materials, one for the evaporating portion and another for the superheating portion of the steam generator. The current MHTGR steam generator design utilizes 2 1/4 CR - 1 Mo material for the economizer/evaporator/initial superheater tube section and Alloy 800H material for the finishing superheat tube section. Therefore, a dissimilar metal weld (DMW) is incorporated in each tube circuit. This feature of the design imposes certain important constraints on the steam generator designer. This paper presents an overview of the MHTGR steam generator conceptual design, and then focuses on the DMW considerations and how these have influenced the design configuration.

Spring, A.H.; Basol, M.

1987-01-01T23:59:59.000Z

103

Helium Ion Microscope | EMSL  

NLE Websites -- All DOE Office Websites (Extended Search)

other characterization capabilities. User Portal Name: Helium Ion Microscope Instrument ID: 34104 Availability: 10 hours a day, 5 days a week Facility: Quiet Wing Quick Specs...

104

Material Control and Accounting Design Considerations for High-Temperature Gas Reactors  

SciTech Connect

The subject of this report is domestic safeguards and security by design (2SBD) for high-temperature gas reactors, focusing on material control and accountability (MC&A). The motivation for the report is to provide 2SBD support to the Next Generation Nuclear Plant (NGNP) project, which was launched by Congress in 2005. This introductory section will provide some background on the NGNP project and an overview of the 2SBD concept. The remaining chapters focus specifically on design aspects of the candidate high-temperature gas reactors (HTGRs) relevant to MC&A, Nuclear Regulatory Commission (NRC) requirements, and proposed MC&A approaches for the two major HTGR reactor types: pebble bed and prismatic. Of the prismatic type, two candidates are under consideration: (1) GA's GT-MHR (Gas Turbine-Modular Helium Reactor), and (2) the Modular High-Temperature Reactor (M-HTR), a derivative of Areva's Antares reactor. The future of the pebble-bed modular reactor (PBMR) for NGNP is uncertain, as the PBMR consortium partners (Westinghouse, PBMR [Pty] and The Shaw Group) were unable to agree on the path forward for NGNP during 2010. However, during the technology assessment of the conceptual design phase (Phase 1) of the NGNP project, AREVA provided design information and technology assessment of their pebble bed fueled plant design called the HTR-Module concept. AREVA does not intend to pursue this design for NGNP, preferring instead a modular reactor based on the prismatic Antares concept. Since MC&A relevant design information is available for both pebble concepts, the pebble-bed HTGRs considered in this report are: (1) Westinghouse PBMR; and (2) AREVA HTR-Module. The DOE Office of Nuclear Energy (DOE-NE) sponsors the Fuel Cycle Research and Development program (FCR&D), which contains an element specifically focused on the domestic (or state) aspects of SBD. This Material Protection, Control and Accountancy Technology (MPACT) program supports the present work summarized in this report, namely the development of guidance to support the consideration of MC&A in the design of both pebble-bed and prismatic-fueled HTGRs. The objective is to identify and incorporate design features into the facility design that will cost effectively aid in making MC&A more effective and efficient, with minimum impact on operations. The theft of nuclear material is addressed through both MC&A and physical protection, while the threat of sabotage is addressed principally through physical protection.

Trond Bjornard; John Hockert

2011-08-01T23:59:59.000Z

105

Modular tokamak magnetic system  

DOE Patents (OSTI)

A modular tokamak system comprised of a plurality of interlocking moldules. Each module is comprised of a vacuum vessel section, a toroidal field coil, moldular saddle coils which generate a poloidal magnetic field and ohmic heating coils.

Yang, Tien-Fang (Wayland, MA)

1988-01-01T23:59:59.000Z

106

Prismatic modular reactor analysis with melcor  

E-Print Network (OSTI)

, the calculation for the heat distribution in the graphite and fuel is unsatisfactory which requires MELCOR modification for the PCC simulation. For future work, a complete model of the NGNP under normal operation conditions will be developed when additional data...

Zhen, Ni

2009-05-15T23:59:59.000Z

107

Energy Department Announces Small Modular Reactor Technology...  

Energy Savers (EERE)

of Agreement (MOA) will help leverage Savannah River's land assets, energy facilities and nuclear expertise to support potential private sector development, testing and licensing...

108

Modular optical detector system  

DOE Patents (OSTI)

A modular optical detector system. The detector system is designed to detect the presence of molecules or molecular species by inducing fluorescence with exciting radiation and detecting the emitted fluorescence. Because the system is capable of accurately detecting and measuring picomolar concentrations it is ideally suited for use with microchemical analysis systems generally and capillary chromatographic systems in particular. By employing a modular design, the detector system provides both the ability to replace various elements of the detector system without requiring extensive realignment or recalibration of the components as well as minimal user interaction with the system. In addition, the modular concept provides for the use and addition of a wide variety of components, including optical elements (lenses and filters), light sources, and detection means, to fit particular needs.

Horn, Brent A. (Livermore, CA); Renzi, Ronald F. (Tracy, CA)

2006-02-14T23:59:59.000Z

109

Laminar Entrained Flow Reactor (Fact Sheet)  

SciTech Connect

The Laminar Entrained Flow Reactor (LEFR) is a modular, lab scale, single-user reactor for the study of catalytic fast pyrolysis (CFP). This system can be employed to study a variety of reactor conditions for both in situ and ex situ CFP.

Not Available

2014-02-01T23:59:59.000Z

110

Steam generator design considerations for modular HTGR plant  

SciTech Connect

Studies are in progress to develop a standard High Temperature Gas-Cooled Reactor (HTGR) plant design that is amenable to serial production and is licensable. Based on the results of trade studies performed in the DOE-funded HTGR program, activities are being focused to emphasize a modular concept based on a 350 MW(t) annular reactor core with prismatic fuel elements. Utilization of a multiplicity of the standard module affords flexibility in power rating for utility electricity generation. The selected modular HTGR concept has the reactor core and heat transport systems housed in separate steel vessels. This paper highlights the steam generator design considerations for the reference plant, and includes a discussion of the major features of the heat exchanger concept and the technology base existing in the US.

McDonald, C.F.; DeFur, D.D.

1986-05-01T23:59:59.000Z

111

Advanced Reactor Technologies | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Advanced Reactor Advanced Reactor Technologies Advanced Reactor Technologies Advanced Reactor Technologies Advanced Reactor Technologies The Office of Advanced Reactor Technologies (ART) sponsors research, development and deployment (RD&D) activities through its Next Generation Nuclear Plant (NGNP), Advanced Reactor Concepts (ARC), and Advanced Small Modular Reactor (aSMR) programs to promote safety, technical, economical, and environmental advancements of innovative Generation IV nuclear energy technologies. The Office of Nuclear Energy (NE) will pursue these advancements through RD&D activities at the Department of Energy (DOE) national laboratories and U.S. universities, as well as through collaboration with industry and international partners. These activities will focus on advancing scientific

112

The Helium Question  

Science Journals Connector (OSTI)

...1976 1977 1978 (%) Kansas 55.34 51.58 48...U.S. naturai gas production, except from Alaska...Cryogenic transmis-sion of electricity, already technically...are so inefficient or site-dependent. Superconductivity...to supplement its own production with heli-um purchased...

Earl Cook

1979-12-07T23:59:59.000Z

113

Effects of sequential tungsten and helium ion implantation on nano-indentation hardness of tungsten  

SciTech Connect

To simulate neutron and helium damage in a fusion reactor first wall sequential self-ion implantation up to 13 dpa followed by helium-ion implantation up to 3000 appm was performed to produce damaged layers of {approx}2 {mu}m depth in pure tungsten. The hardness of these layers was measured using nanoindentation and was studied using transmission electron microscopy. Substantial hardness increases were seen in helium implanted regions, with smaller hardness increases in regions which had already been self-ion implanted, thus, containing pre-existing dislocation loops. This suggests that, for the same helium content, helium trapped in distributed vacancies gives stronger hardening than helium trapped in vacancies condensed into dislocation loops.

Armstrong, D. E. J.; Edmondson, P. D.; Roberts, S. G. [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom)] [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom)

2013-06-24T23:59:59.000Z

114

Modular low aspect ratio-high beta torsatron  

DOE Patents (OSTI)

A fusion reactor device in which the toroidal magnetic field and at least a portion of the poloidal magnetic field are provided by a single set of modular coils. The coils are arranged on the surface of a low aspect ratio toroid in planes having the cylindrical coordinate relationship .phi.=.phi..sub.i +kz where k is a constant equal to each coil's pitch and .phi..sub.i is the toroidal angle at which the i'th coil intersects the z=o plane. The device may be described as a modular, high beta torsation whose screw symmetry is pointed along the systems major (z) axis. The toroid defined by the modular coils preferably has a racetrack minor cross section. When vertical field coils and preferably a toroidal plasma current are provided for magnetic field surface closure within the toroid, a vacuum magnetic field of racetrack shaped minor cross section with improved stability and beta valves is obtained.

Sheffield, George V. (Hopewell, NJ); Furth, Harold P. (Princeton, NJ)

1984-02-07T23:59:59.000Z

115

IMPROVEMENTS OF HELIUM LIQUEFACTION/REFRIGERATION PLANTS AND APPLICATIONS  

Science Journals Connector (OSTI)

Design features for a new range of helium liquefiers and refrigerators with capacities ranging from 30 to 280 l/h of liquid helium (LHe) and 100 to 900 Watt respectively. The latest He cold box development shows an increased efficiency due to improved turbine and heat exchanger design. Other benefits of the new design include short cool-down times and a very compact design which offers better flexibility and process control. The modularity of the system was designed in order to cover a wide range of applications like sophisticated shield cooling at different temperature levels or simultaneous operation modes for He liquefaction and refrigeration purposes. The presentation will highlight the individual improvements in the design.

K.-H. Berdais; H. Wilhelm; Th. Ungricht

2008-01-01T23:59:59.000Z

116

Preheating After Modular Inflation  

E-Print Network (OSTI)

We study (p)reheating in modular (closed string) inflationary scenarios, with a special emphasis on Kahler moduli/Roulette models. It is usually assumed that reheating in such models occurs through perturbative decays. However, we find that there are very strong non-perturbative preheating decay channels related to the particular shape of the inflaton potential (which is highly nonlinear and has a very steep minimum). Preheating after modular inflation, proceeding through a combination of tachyonic instability and broad-band parametric resonance, is perhaps the most violent example of preheating after inflation known in the literature. Further, we consider the subsequent transfer of energy to the standard model sector in scenarios where the standard model particles are confined to a D7-brane wrapping the inflationary blow-up cycle of the compactification manifold or, more interestingly, a non-inflationary blow up cycle. We explicitly identify the decay channels of the inflaton in these two scenarios. We also consider the case where the inflationary cycle shrinks to the string scale at the end of inflation; here a field theoretical treatment of reheating is insufficient and one must turn instead to a stringy description. We estimate the decay rate of the inflaton and the reheat temperature for various scenarios.

Neil Barnaby; J. Richard Bond; Zhiqi Huang; Lev Kofman

2009-09-02T23:59:59.000Z

117

Heavy Liquid Metal Reactor Development - Nuclear Engineering Division  

NLE Websites -- All DOE Office Websites (Extended Search)

> Heavy Liquid Metal Reactor Development > Heavy Liquid Metal Reactor Development Capabilities Nuclear Systems Modeling and Design Analysis Reactor Physics and Fuel Cycle Analysis Nuclear Data Program Advanced Reactor Development Overview Advanced Fast Reactor (AFR) Heavy Liquid Metal Reactor Development Generation IV Nuclear Waste Form and Repository Performance Modeling Nuclear Energy Systems Design and Development Other Capabilities Work with Argonne Contact us For Employees Site Map Help Advanced Reactor Development and Technology Heavy Liquid Metal Reactor Development Bookmark and Share STAR-LM: Simplified, Modular, Small Reactor Featuring Flow-thru Fuel Cartridge STAR-LM: Simplified, Modular, Small Reactor Featuring Flow-thru Fuel Cartridge. Click on image to view larger image. Argonne has traditionally been the foremost institute in the US for

118

Honeywell modular automation system acceptance test report  

SciTech Connect

This document provides the results of the Acceptance Test Procedure for the Honeywell Modular Automation System.

Cunningham, L.T., Westinghouse Hanford

1996-06-14T23:59:59.000Z

119

Modular Optical PDV System  

SciTech Connect

A modular optical photon Doppler velocimetry (PDV) detector system has been developed by using readily available optical components with a 20-GHz Miteq optical detector into eight channels of single-wide modules integrated into a 3U rack unit (1U = 1.75 inches) with a common power supply. Optical fibers were precisely trimmed, welded, and timed within each unit. This system has been used to collect dynamic velocity data on various physics experiments. An optical power meter displays the laser input power to the module and optical power at the detector. An adjustable micro-electromechanical system (MEMS) optical attenuator is used to adjust the amount of unshifted light entering the detector. Front panel LEDs show the presence of power to the module. A fully loaded chassis with eight channels consumes 45 watts of power. Each chassis requires 1U spacing above and below for heat management. Modules can be easily replaced.

Araceli Rutkowski, David Esquibel

2008-12-11T23:59:59.000Z

120

Helium dilution refrigeration system  

DOE Patents (OSTI)

A helium dilution refrigeration system operable over a limited time period, and recyclable for a next period of operation. The refrigeration system is compact with a self-contained pumping system and heaters for operation of the system. A mixing chamber contains .sup.3 He and .sup.4 He liquids which are precooled by a coupled container containing .sup.3 He liquid, enabling the phase separation of a .sup.3 He rich liquid phase from a dilute .sup.3 He-.sup.4 He liquid phase which leads to the final stage of a dilution cooling process for obtaining low temperatures. The mixing chamber and a still are coupled by a fluid line and are maintained at substantially the same level with the still cross sectional area being smaller than that of the mixing chamber. This configuration provides maximum cooling power and efficiency by the cooling period ending when the .sup.3 He liquid is depleted from the mixing chamber with the mixing chamber nearly empty of liquid helium, thus avoiding unnecessary and inefficient cooling of a large amount of the dilute .sup.3 He-.sup.4 He liquid phase.

Roach, Patrick R. (Darien, IL); Gray, Kenneth E. (Naperville, IL)

1988-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modular helium reactor" 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

Nuclear Reactor Technologies | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Reactor Technologies Reactor Technologies Nuclear Reactor Technologies TVA Watts Bar Nuclear Power Plant | Photo courtesy of Tennessee Valley Authority TVA Watts Bar Nuclear Power Plant | Photo courtesy of Tennessee Valley Authority Nuclear power has reliably and economically contributed almost 20% of electrical generation in the United States over the past two decades. It remains the single largest contributor (more than 70%) of non-greenhouse-gas-emitting electric power generation in the United States. Small Modular Reactor Technologies Small modular reactors can also be made in factories and transported to sites where they would be ready to "plug and play" upon arrival, reducing both capital costs and construction times. The smaller size also makes these reactors ideal for small electric grids and for locations that

122

Helium effects on the mechanical properties of neutron-irradiated Cr-Mo ferritic steels  

SciTech Connect

In the first wall of a fusion rector, large amounts of transmutation helium will be produced simultaneously with the displacement damage caused by high-energy neutrons from the fusion reaction. One method used to simulate irradiation effects for ferritic steels is to add nickel to the steels and irradiate them in a mixed-spectrum reactor. Fast neutrons in the spectrum produce displacement damage, while transmutation helium is produced by a two-step reaction of {sup 58}Ni with thermal neutrons. This technique has been used to investigate the effect of helium on tensile properties and toughness. Results from these studies are summarized.

Klueh, R.L.

1990-01-01T23:59:59.000Z

123

Modular Isotopic Thermoelectric Generator  

SciTech Connect

Advanced RTG concepts utilizing improved thermoelectric materials and converter concepts are under study at Fairchild for DOE. The design described here is based on DOE's newly developed radioisotope heat source, and on an improved silicon-germanium material and a multicouple converter module under development at Syncal. Fairchild's assignment was to combine the above into an attractive power system for use in space, and to assess the specific power and other attributes of that design. The resultant design is highly modular, consisting of standard RTG slices, each producing ~24 watts at the desired output voltage of 28 volt. Thus, the design could be adapted to various space missions over a wide range of power levels, with little or no redesign. Each RTG slice consists of a 250-watt heat source module, eight multicouple thermoelectric modules, and standard sections of insulator, housing, radiator fins, and electrical circuit. The design makes it possible to check each thermoelectric module for electrical performance, thermal contact, leaktightness, and performance stability, after the generator is fully assembled; and to replace any deficient modules without disassembling the generator or perturbing the others. The RTG end sections provide the spring-loaded supports required to hold the free-standing heat source stack together during launch vibration. Details analysis indicates that the design offers a substantial improvement in specific power over the present generator of RTGs, using the same heat source modules. There are three copies in the file.

Schock, Alfred

1981-04-03T23:59:59.000Z

124

The Helium Question  

Science Journals Connector (OSTI)

...inland. high-temperature gas reactors, high-tem-perature gas turbines, laser-based mis-sile-defense...all U.S. proved natural-gas reserves and prob-ably exceeds...content of all natural gas remaining to be produced in the United...

Earl Cook

1979-12-07T23:59:59.000Z

125

Modular low-aspect-ratio high-beta torsatron  

DOE Patents (OSTI)

A fusion-reactor device is described which the toroidal magnetic field and at least a portion of the poloidal magnetic field are provided by a single set of modular coils. The coils are arranged on the surface of a low-aspect-ratio toroid in planed having the cylindrical coordinate relationship phi = phi/sub i/ + kz, where k is a constant equal to each coil's pitch and phi/sub i/ is the toroidal angle at which the i'th coil intersects the z = o plane. The toroid defined by the modular coils preferably has a race track minor cross section. When vertical field coils and, preferably, a toroidal plasma current are provided for magnetic-field-surface closure within the toroid, a vacuum magnetic field of racetrack-shaped minor cross section with improved stability and beta valves is obtained.

Sheffield, G.V.

1982-04-01T23:59:59.000Z

126

The Viscosity of Liquid Helium  

Science Journals Connector (OSTI)

2 September 1935 research-article The Viscosity of Liquid Helium J. O. Wilhelm A. D. Misener A. R. Clark The Royal Society is collaborating with JSTOR to digitize, preserve...

1935-01-01T23:59:59.000Z

127

Roughening transition and helium crystals  

Science Journals Connector (OSTI)

Crystal shapes or crystal growth mechanisms depend drastically on whether the crystal surface is smooth or rough, i.e. whether the temperature is lower or higher than its roughening temperature. Helium appeared r...

S. Balibar; F. Gallet; E. Rolley; P. E. Wolf

1985-01-01T23:59:59.000Z

128

Liquid helium cryo TEM | EMSL  

NLE Websites -- All DOE Office Websites (Extended Search)

cryo TEM Liquid helium cryo TEM The JEOL JEM-3000SFF was designed for high-resolution cryogenic transmission electron microscopy (cryo-EM) of biological samples and expands EMSL...

129

Radiation field modeling and optimization of a compact and modular  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiation field modeling and optimization of a compact and modular Radiation field modeling and optimization of a compact and modular multi-plate photocatalytic reactor (MPPR) for air/water purification by Monte Carlo method Title Radiation field modeling and optimization of a compact and modular multi-plate photocatalytic reactor (MPPR) for air/water purification by Monte Carlo method Publication Type Journal Article Year of Publication 2013 Authors Zazueta, Ana Luisa Loo, Hugo Destaillats, and Gianluca Li Puma Journal Chemical Engineering Journal Volume 217 Pagination 475-485 Date Published 02/01/2013 Abstract The radiation field in a multi-plate photocatalytic reactor (MPPR) for air or water purification was modeled and optimized using a Monte Carlo stochastic method. The MPPR consists of parallel photocatalytic plates irradiated by cylindrical UV lamps orthogonal to the plates. The photocatalyst titanium dioxide (TiO2) is supported on the plates as a thin film. The photoreactor design is compact and offers a large irradiated photocatalytic surface area, a high degree of photon utilization, low pressure drop and a modular design which can facilitate scale-up. These features are desirable for the decontamination of indoor air in ventilation ducts or for water detoxification. The Monte Carlo method was applied to determine three dimensionless reactor performance parameters: the photon absorption efficiency (Φ), the uniformity of the distribution of the dimensionless radiation intensity (η) and the overall photonic efficiency (Φ). The emission of photons from the light sources was simulated by the extensive source with superficial emission (ESSE) model. Simulations were performed by varying the catalyst reflectivity albedo, the number and the diameter of lamps, and the dimensions and spacing of the photocatalytic plates. Optimal design for a basic reactor module with one lamp was accomplished for lamp-diameter-to-plate-height ratio (β) of 0.7, while the plate-spacing-to-plate-height ratio (α) was correlated by [αoptimum = 0.191 β2 - 0.5597 β + 0.3854]. A multilamp arrangement leads to a feasible increase in the size and number of the plates and the irradiated photocatalytic surface area. The optimum design was validated by measuring the apparent quantum yield of the oxidation of toluene (7 ppmv) in a humidified air stream using immobilized TiO2 (Degussa P25). Experiments performed varying the geometrical parameter α correlated well with the model calculations, with maximum apparent quantum yield for α = 0.137. The results are directly transferable to the treatment of water by photocatalysis.

130

Invertible Program Restructurings for Continuing Modular Maintenance  

E-Print Network (OSTI)

Invertible Program Restructurings for Continuing Modular Maintenance Julien Cohen ASCOLA team (EMN in main- tenance with invertible program transformations. We illustrate this on the typical Expression problems with our approach. Keywords-modular maintenance; restructuring; invertible pro- gram

Paris-Sud XI, Université de

131

Modular multivariable control improves hydrocracking  

SciTech Connect

Modular multivariable control (MMC), a system of interconnected, single process variable controllers, can be a user-friendly, reliable and cost-effective alternative to centralized, large-scale multivariable control packages. MMC properties and features derive directly from the properties of the coordinated controller which, in turn, is based on internal model control technology. MMC was applied to a hydrocracking unit involving two process variables and three controller outputs. The paper describes modular multivariable control, MMC properties, tuning considerations, application at the DCS level, constraints handling, and process application and results.

Chia, T.L.; Lefkowitz, I. [ControlSoft, Inc., Cleveland, OH (United States); Tamas, P.D. [Marathon Oil Co., Robinson, IL (United States)

1996-10-01T23:59:59.000Z

132

Acoustics of modular constructionIndustry overview  

Science Journals Connector (OSTI)

This session will provide an overview of the issues and efforts impacting the commercial modular construction industry throughout North America with particular focus on acoustics in relocatable classrooms. The Modular Building Institute is the international nonprofit trade association representing manufacturers and dealers of commercial modular facilites both temporary and permanent serving educational health care retail industrial military and multi?family markets.

Thomas E. Hardiman

2007-01-01T23:59:59.000Z

133

Conception design of helium ion FFAG accelerator with induction accelerating cavity  

E-Print Network (OSTI)

In the recent decades of particle accelerator R&D area, fixed field alternating gradient (FFAG) accelerator has become a highlight for some advantages of its higher beam intensity and lower cost, although there are still some technical challenges. In this paper, FFAG accelerator is adopted to accelerate helium ion beam on the one hand for the study of helium embrittlement on fusion reactor envelope material and on the other hand for promoting the conception research and design of FFAG accelerator and exploring the possibility of developing high power FFAG accelerators. The conventional period focusing unit of helium ion FFAG accelerator and three-dimensional model of the large aperture combinatorial magnet by OPERA-TOSCA are given. For low energy and low revolution frequency, induction acceleration is proposed to replace conventional radio frequency(RF) acceleration for helium ion FFAG accelerator, which avoids the potential breakdown of acceleration field caused by wake field and improves the acceleratio...

Huan-li, Luo; Xiang-qi, Wang; Hong-Liang, Xu

2013-01-01T23:59:59.000Z

134

Two low-cost, modular sub-? test cryostats  

SciTech Connect

Two general-purpose liquid helium (LHe) test cryostats have been developed in support of a major upgrade to the Advanced Photon Source (APS) at Argonne National Laboratory (ANL). The cryostats are capable of sustained operation below 1.8 K and currently support tests of prototype superconducting rf (srf) cavities for the APS Upgrades Short Pulse X-ray (SPX) initiative. To save cost, two existing test vessels were reconditioned: one bucket dewar supporting bare cavity tests and one shielded vacuum vessel with an integral LHe reservoir for jacketed/dressed cavity tests. A new feedbox containing a heat exchanger and associated valves was also designed and fabricated to support either cryostat. The resulting modular design permits tests on a wide variety of srf cavities in various states of completion, minimizing cost and maximizing use of the hardware. Together with a dedicated vacuum pump, control system, and helium supply via storage dewar or cryoplant, these cryostats are vital to the srf cavity development effort within the APS Upgrade.

Fuerst, J. D.; Kaluzny, J. A. [Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States)

2014-01-29T23:59:59.000Z

135

Nuclear Reactor (atomic reactor)  

Science Journals Connector (OSTI)

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

2008-01-01T23:59:59.000Z

136

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

E-Print Network (OSTI)

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

Frisani, Angelo

2011-08-08T23:59:59.000Z

137

Helium Refrigerator Design for Pulsed Heat Load in Tokamaks  

SciTech Connect

Nuclear fusion reactors of the Tokamak type will be operated in a pulsed mode requiring the helium refrigerator to remove periodically large heat loads in time steps of approximately one hour. What are the necessary steps for a refrigerator to cope with such load variations?A series of numerical simulations has been performed indicating the possibility of an active refrigerator control with low exergetic losses. A basic comparison is made between the largest existing refrigerator sizes and the size required to service for example the ITER requirements.

Kuendig, A.; Schoenfeld, H. [Linde Kryotechnik AG, Dattlikonerstrasse 5, CH-8422 Pfungen (Switzerland)

2006-04-27T23:59:59.000Z

138

Use of Multiple Reheat Helium Brayton Cycles to Eliminate the Intermediate Heat Transfer Loop for Advanced Loop Type SFRs  

SciTech Connect

The sodium intermediate heat transfer loop is used in existing sodium cooled fast reactor (SFR) plant design as a necessary safety measure to separate the radioactive primary loop sodium from the water of the steam Rankine power cycle. However, the intermediate heat transfer loop significantly increases the SFR plant cost and decreases the plant reliability due to the relatively high possibility of sodium leakage. A previous study shows that helium Brayton cycles with multiple reheat and intercooling for SFRs with reactor outlet temperature in the range of 510C to 650C can achieve thermal efficiencies comparable to or higher than steam cycles or recently proposed supercritical CO2 cycles. Use of inert helium as the power conversion working fluid provides major advantages over steam or CO2 by removing the requirement for safety systems to prevent and mitigate the sodium-water or sodium-CO2 reactions. A helium Brayton cycle power conversion system therefore makes the elimination of the intermediate heat transfer loop possible. This paper presents a pre-conceptual design of multiple reheat helium Brayton cycle for an advanced loop type SFR. This design widely refers the new horizontal shaft distributed PBMR helium power conversion design features. For a loop type SFR with reactor outlet temperature 550C, the design achieves 42.4% thermal efficiency with favorable power density comparing with high temperature gas cooled reactors.

Haihua Zhao; Hongbin Zhang; Samuel E. Bays

2009-05-01T23:59:59.000Z

139

Optimization of actinide transmutation in innovative lead-cooled fast reactors  

E-Print Network (OSTI)

The thesis investigates the potential of fertile free fast lead-cooled modular reactors as efficient incinerators of plutonium and minor actinides (MAs) for application to dedicated fuel cycles for transmutation. A methodology ...

Romano, Antonino, 1972-

2003-01-01T23:59:59.000Z

140

Microsoft Word - 20.1 Special Study Reactor Type Comparison_VS...  

NLE Websites -- All DOE Office Websites (Extended Search)

Heat Source NRC Nuclear Regulatory Commission PBMR Pebble Bed Modular Reactor PHP Process Heat Plant PLOFC Pressurized Loss of Forced Cooling QA Quality Assurance R&D Research and...

Note: This page contains sample records for the topic "modular helium reactor" 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

Assessment of Embrittlement of VHTR Structural Alloys in Impure Helium Environments  

SciTech Connect

The helium coolant in high-temperature reactors inevitably contains low levels of impurities during steady-state operation, primarily consisting of small amounts of H{sub 2}, H{sub 2}O, CH{sub 4}, CO, CO{sub 2}, and N{sub 2} from a variety of sources in the reactor circuit. These impurities are problematic because they can cause significant long-term corrosion in the structural alloys used in the heat exchangers at elevated temperatures. Currently, the primary candidate materials for intermediate heat exchangers are Alloy 617, Haynes 230, Alloy 800H, and Hastelloy X. This project will evaluate the role of impurities in helium coolant on the stress-assisted grain boundary oxidation and creep crack growth in candidate alloys at elevated temperatures. The project team will: Evaluate stress-assisted grain boundary oxidation and creep crack initiation and crack growth in the temperature range of 500-850C in a prototypical helium environment. Evaluate the effects of oxygen partial pressure on stress-assisted grain boundary oxidation and creep crack growth in impure helium at 500C, 700C, and 850C respectively. Characterize the microstructure of candidate alloys after long-term exposure to an impure helium environment in order to understand the correlation between stress-assisted grain boundary oxidation, creep crack growth, material composition, and impurities in the helium coolant. Evaluate grain boundary engineering as a method to mitigate stress-assisted grain boundary oxidation and creep crack growth of candidate alloys in impure helium. The maximum primary helium coolant temperature in the high-temperature reactor is expected to be 850-1,000C.Corrosion may involve oxidation, carburization, or decarburization mechanisms depending on the temperature, oxygen partial pressure, carbon activity, and alloy composition. These corrosion reactions can substantially affect long-term mechanical properties such as crack- growth rate and fracture toughness, creep rupture, and fatigue. Although there are some studies on the effects of impurities in helium coolant on creep rupture and fatigue strength, very little is known about their effects on creep crack initiation and crack growth rate at elevated temperatures.

Crone, Wendy; Cao, Guoping; Sridhara, Kumar

2013-05-31T23:59:59.000Z

142

Cryogenic system with GM cryocooler for krypton, xenon separation from hydrogen-helium purge gas  

SciTech Connect

In the thorium molten salt reactor (TMSR), fission products such as krypton, xenon and tritium will be produced continuously in the process of nuclear fission reaction. A cryogenic system with a two stage GM cryocooler was designed to separate Kr, Xe, and H{sub 2} from helium purge gas. The temperatures of two stage heat exchanger condensation tanks were maintained at about 38 K and 4.5 K, respectively. The main fluid parameters of heat transfer were confirmed, and the structural heat exchanger equipment and cold box were designed. Designed concentrations after cryogenic separation of Kr, Xe and H{sub 2} in helium recycle gas are less than 1 ppb.

Chu, X. X.; Zhang, D. X.; Qian, Y.; Liu, W. [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201800 (China); Zhang, M. M.; Xu, D. [Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190 (China)

2014-01-29T23:59:59.000Z

143

Modular CHP System for Utica College: Design Specification, March...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Modular CHP System for Utica College: Design Specification, March 2007 Modular CHP System for Utica College: Design Specification, March 2007 This paper describes Utica College's...

144

Regulator of modular units and Mahler measures.  

E-Print Network (OSTI)

We present a proof of the formula, due to Mellit and Brunault, which evaluates an integral of the regulator of two modular units to the value of the $L$-series of a modular form of weight 2 at $s=2$. Applications of the formula to computing Mahler measures are discussed.

Wadim Zudilin.

145

Performance and Safety Analysis of a Generic Small Modular Reactor  

E-Print Network (OSTI)

for spent fuel from a Westinghouse AP1000. The results showed that from a fuel material standpoint, the SMR and AP1000 had effectively the same PR value. Unable to analyze security systems and methods employed at specific nuclear power plant sites...

Kitcher, Evans Damenortey, 1987-

2012-11-07T23:59:59.000Z

146

CESAR: Center for Exascale Simulation of Advanced Reactors | Argonne  

NLE Websites -- All DOE Office Websites (Extended Search)

CESAR: Center for Exascale Simulation of Advanced Reactors CESAR: Center for Exascale Simulation of Advanced Reactors CESAR: Center for Exascale Simulation of Advanced Reactors CESAR is an interdisciplinary center for developing an innovative, next-generation nuclear reactor analysis tool that both utilizes and guides the development of exascale computing platforms. Existing reactor analysis codes are highly tuned and calibrated for commercial light-water reactors, but they lack the physics fidelity to seamlessly carry over to new classes of reactors with significantly different design characteristics-as, for example, innovative concepts such as TerraPower's Traveling Wave reactor and Small Modular Reactor concepts. Without vastly improved modeling capabilities, the economic and safety characteristics of these and other novel systems will require tremendous

147

Neutron-induced dpa, transmutations, gas production, and helium embrittlement of fusion materials  

E-Print Network (OSTI)

In a fusion reactor materials will be subjected to significant fluxes of high-energy neutrons. As well as causing radiation damage, the neutrons also initiate nuclear reactions leading to changes in the chemical composition of materials (transmutation). Many of these reactions produce gases, particularly helium, which cause additional swelling and embrittlement of materials. This paper investigates, using a combination of neutron-transport and inventory calculations, the variation in displacements per atom (dpa) and helium production levels as a function of position within the high flux regions of a recent conceptual model for the "next-step" fusion device DEMO. Subsequently, the gas production rates are used to provide revised estimates, based on new density-functional-theory results, for the critical component lifetimes associated with the helium-induced grain-boundary embrittlement of materials. The revised estimates give more optimistic projections for the lifetimes of materials in a fusion power plant co...

Gilbert, M R; Nguyen-Manh, D; Zheng, S; Packer, L W; Sublet, J -Ch

2013-01-01T23:59:59.000Z

148

On the Triplets of Helium  

Science Journals Connector (OSTI)

It is well known that the inversion of the helium triplets and their deviation from interval rule are due to the spin-other-orbit and to the magnetic spin-spin interactions (respectively), which may be neglected in comparison with the spin-orbit interaction in treating the spectra of heavy elements. The preliminary calculation of Heisenberg is compared with the correct calculation of Breit for the lowest triplet. The extension to higher triplets, by Araki, is simplified and generalized, and the comparison with experiment is discussed.

D. R. Inglis

1942-03-01T23:59:59.000Z

149

Neutron Scattering from Liquid Helium at Large Momentum Transfer  

Science Journals Connector (OSTI)

......letter Letters to the Editor Neutron Scattering from Liquid Helium at Large...Vol. 46 (1971), No. 1 Neutron Scattering from Liquid Helium at Large...Feynman diagram for the elastic scattering of a neutron from liquid helium, where......

Sigenobu Sunakawa; Kazuo Okajima; Kiyohisa Matsuda

1971-07-01T23:59:59.000Z

150

TEPP Training - Modular Emergency Response Radiological Transportation  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Services » Waste Management » Packaging and Transportation » Services » Waste Management » Packaging and Transportation » Transportation Emergency Preparedness Program » TEPP Training - Modular Emergency Response Radiological Transportation Training (MERRTT) TEPP Training - Modular Emergency Response Radiological Transportation Training (MERRTT) Once the jurisdiction has completed an evaluation of their plans and procedures, they will need to address any gaps in training. To assist, TEPP has developed the Modular Emergency Response Radiological Transportation Training (MERRTT) program. MERRTT provides fundamental knowledge for responding to transportation incidents involving radiological material and builds on training in existing hazardous materials curricula. MERRTT satisfies the training requirements outlined in the Waste Isolation Pilot

151

Modular design for increasing assembly automation  

Science Journals Connector (OSTI)

Abstract Modular design can address the need for a high number of product variants and further allow a higher degree of automation in the assembly line. A framework is developed for the simultaneous modular product design and the design of automated manufacturing system. Product designs are optimized for automation using Design Structure Matrix and Modular Function Deployment. Alternative production systems are designed and accessed based on the analysis of assembly steps hierarchically. The implementation of the framework on the design of a production system for furniture assembly, able to handle multiple variants with a large number of components, is demonstrated.

Konstantinos Salonitis

2014-01-01T23:59:59.000Z

152

Compound cryopump for fusion reactors  

E-Print Network (OSTI)

We reconsider an old idea: a three-stage compound cryopump for use in fusion reactors such as DEMO. The helium "ash" is adsorbed on a 4.5 K charcoal-coated surface, while deuterium and tritium are adsorbed at 15-22 K on a second charcoal-coated surface. The helium is released by raising the first surface to ~30 K. In a separate regeneration step, deuterium and tritium are released at ~110 K. In this way, the helium can be pre-separated from other species. In the simplest design, all three stages are in the same vessel, with a single valve to close the pump off from the tokamak during regeneration. In an alternative design, the three stages are in separate vessels, connected by valves, allowing the stages to regenerate without interfering with each other. The inclusion of the intermediate stage would not affect the overall pumping speed significantly. The downstream exhaust processing system could be scaled down, as much of the deuterium and tritium could be returned directly to the reactor. This could reduce ...

Kovari, M; Shephard, T

2013-01-01T23:59:59.000Z

153

Superfluid helium as a technical coolant  

E-Print Network (OSTI)

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

Lebrun, P

1997-01-01T23:59:59.000Z

154

A MODULAR, SCALABLE, ARCHITECTURE FOR UNMANNED VEHICLES  

E-Print Network (OSTI)

1 A MODULAR, SCALABLE, ARCHITECTURE FOR UNMANNED VEHICLES David G. Armstrong II, Carl D. Crane III://www.me.ufl.edu/CIMAR Ralph English Wintec, Inc. Ft. Walton Beach, Florida Phillip Adsit Applied Research Associates Tyndall

Florida, University of

155

Honeywell modular automation system computer software documentation  

SciTech Connect

This document provides a Computer Software Docuemntation for a new Honeywell Modular Automation System (MAS) being installed in the Plutonium Finishing Plant (PFP). This system will be used to control new thermal stabilization furnaces in HA-21I.

Cunningham, L.T.

1997-01-20T23:59:59.000Z

156

A design flow based on modular refinement  

E-Print Network (OSTI)

We propose a practical methodology based on modular refinement to design complex systems. The methodology relies on modules with latency-insensitive interfaces so that the refinements can change the timing contract of a ...

Dave, Nirav H.

157

Design of a modular motorcycle windshield wiper  

E-Print Network (OSTI)

Motorcycle windshield wipers are essentially non-existent in the United States. Customer and market research reveals a demand for such a product. This paper explores the product viability of a modular motorcycle windshield ...

Boyd, Robert Allen Michael

2010-01-01T23:59:59.000Z

158

Modular ITT Module D Modular ITT Module D Version 1 16/02/2012  

E-Print Network (OSTI)

manage health and safety at work. Your responses should include: basic statement on safety awarenessModular ITT ­ Module D Modular ITT ­ Module D Version 1 16/02/2012 Module D ­ Health & Safety an overall failing of your bid. This section allows us to assess your competency for health and safety. We

159

Figure 1. Recurrent modular network architecture Recurrent modular network architecture for sea ice  

E-Print Network (OSTI)

). Classification of sea ice in MIZ is important for navigation in these regions and for accurate evaluation of heatFigure 1. Recurrent modular network architecture Recurrent modular network architecture for sea ice classification in the Marginal Ice Zone using ERS SAR images Andrey V. Bogdanov1a , Marc Toussaint1b , Stein

Toussaint, Marc

160

Helium refrigeration considerations for cryomodule design  

SciTech Connect

Many of the present day accelerators are based on superconducting radio frequency (SRF) cavities, packaged in cryo-modules (CM), which depend on helium refrigeration at sub-atmospheric pressures, nominally 2 K. These specialized helium refrigeration systems are quite cost intensive to produce and operate. Particularly as there is typically no work extraction below the 4.5-K supply, it is important that the exergy loss between this temperature level and the CM load temperature(s) be minimized by the process configuration choices. This paper will present, compare and discuss several possible helium distribution process arrangements to support the CM loads.

Ganni, V.; Knudsen, P. [Thomas Jefferson National Accelerator Facility (JLab), Newport News, VA 23606 (United States)

2014-01-29T23:59:59.000Z

Note: This page contains sample records for the topic "modular helium reactor" 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

Thermal hydraulic design of a 2400 MW t?h? direct supercritical CO?-cooled fast reactor  

E-Print Network (OSTI)

The gas cooled fast reactor (GFR) has received new attention as one of the basic concepts selected by the Generation-IV International Forum (GIF) for further investigation. Currently, the reference GFR is a helium-cooled ...

Pope, Michael A. (Michael Alexander)

2006-01-01T23:59:59.000Z

162

Lessons Learned From Gen I Carbon Dioxide Cooled Reactors  

SciTech Connect

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

David E. Shropshire

2004-04-01T23:59:59.000Z

163

Advanced Modular Inverter Technology Development  

SciTech Connect

Electric and hybrid-electric vehicle systems require an inverter to convert the direct current (DC) output of the energy generation/storage system (engine, fuel cells, or batteries) to the alternating current (AC) that vehicle propulsion motors use. Vehicle support systems, such as lights and air conditioning, also use the inverter AC output. Distributed energy systems require an inverter to provide the high quality AC output that energy system customers demand. Today's inverters are expensive due to the cost of the power electronics components, and system designers must also tailor the inverter for individual applications. Thus, the benefits of mass production are not available, resulting in high initial procurement costs as well as high inverter maintenance and repair costs. Electricore, Inc. (www.electricore.org) a public good 501 (c) (3) not-for-profit advanced technology development consortium assembled a highly qualified team consisting of AeroVironment Inc. (www.aerovironment.com) and Delphi Automotive Systems LLC (Delphi), (www.delphi.com), as equal tiered technical leads, to develop an advanced, modular construction, inverter packaging technology that will offer a 30% cost reduction over conventional designs adding to the development of energy conversion technologies for crosscutting applications in the building, industry, transportation, and utility sectors. The proposed inverter allows for a reduction of weight and size of power electronics in the above-mentioned sectors and is scalable over the range of 15 to 500kW. The main objective of this program was to optimize existing AeroVironment inverter technology to improve power density, reliability and producibility as well as develop new topology to reduce line filter size. The newly developed inverter design will be used in automotive and distribution generation applications. In the first part of this program the high-density power stages were redesigned, optimized and fabricated. One of the main tasks was to design and validate new gate drive circuits to provide the capability of high temp operation. The new power stages and controls were later validated through extensive performance, durability and environmental tests. To further validate the design, two power stages and controls were integrated into a grid-tied load bank test fixture, a real application for field-testing. This fixture was designed to test motor drives with PWM output up to 50kW. In the second part of this program the new control topology based on sub-phases control and interphase transformer technology was successfully developed and validated. The main advantage of this technology is to reduce magnetic mass, loss and current ripple. This report summarizes the results of the advanced modular inverter technology development and details: (1) Power stage development and fabrication (2) Power stage validation testing (3) Grid-tied test fixture fabrication and initial testing (4) Interphase transformer technology development

Adam Szczepanek

2006-02-04T23:59:59.000Z

164

Phase transitions of helium in aerogel  

Science Journals Connector (OSTI)

The effect of dilute quenched impurities on the liquid-vapor critical point, superfluid and He3?He4 phase separation transitions were studied by introducing liquid helium into aerogel. Aerogel is a highly porous ...

M. H. W. Chan

1996-01-01T23:59:59.000Z

165

Equation of state of metallic helium  

SciTech Connect

The effective ion-ion interaction, free energy, pressure, and electric resistance of metallic liquid helium have been calculated in wide density and temperature ranges using perturbation theory in the electron-ion interaction potential. In the case of conduction electrons, the exchange interaction has been taken into account in the random-phase approximation and correlations have been taken into account in the local-field approximation. The solid-sphere model has been used for the nuclear subsystem. The diameter of these spheres is the only parameter of this theory. The diameter and density of the system at which the transition of helium from the singly ionized to doubly ionized state occurs have been estimated by analyzing the pair effective interaction between helium atoms. The case of doubly ionized helium atoms has been considered. Terms up to the third order of perturbation theory have been taken into account in the numerical calculations. The contribution of the third-order term is significant in all cases. The electric resistance and its temperature dependence for metallic helium are characteristic of simple divalent metals in the liquid state. The thermodynamic parameters-temperature and pressure densities-are within the ranges characteristic of the central regions of giant planets. This makes it possible to assume the existence of helium in the metallic state within the solar system.

Shvets, V. T., E-mail: tarval@breezein.net [Odessa State Academy of Refrigeration (Ukraine)

2013-01-15T23:59:59.000Z

166

Modular cell biology: retroactivity and insulation Domitilla Del Vecchio1,  

E-Print Network (OSTI)

Modular cell biology: retroactivity and insulation Domitilla Del Vecchio1, *, Alexander J Ninfa2 a remarkable insulation property, due to the fast timescales of the phosphorylation and dephosphorylation: computational methods; metabolic and regulatory networks Keywords: feedback; insulation; modularity; singular

Sontag, Eduardo

167

A comparison of radioactive waste from first generation fusion reactors and fast fission reactors with actinide recycling  

SciTech Connect

Limitations of the fission fuel resources will presumably mandate the replacement of thermal fission reactors by fast fission reactors that operate on a self-sufficient closed fuel cycle. This replacement might take place within the next one hundred years, so the direct competitors of fusion reactors will be fission reactors of the latter rather than the former type. Also, fast fission reactors, in contrast to thermal fission reactors, have the potential for transmuting long-lived actinides into short-lived fission products. The associated reduction of the long-term activation of radioactive waste due to actinides makes the comparison of radioactive waste from fast fission reactors to that from fusion reactors more rewarding than the comparison of radioactive waste from thermal fission reactors to that from fusion reactors. Radioactive waste from an experimental and a commercial fast fission reactor and an experimental and a commercial fusion reactor has been characterized. The fast fission reactors chosen for this study were the Experimental Breeder Reactor 2 and the Integral Fast Reactor. The fusion reactors chosen for this study were the International Thermonuclear Experimental Reactor and a Reduced Activation Ferrite Helium Tokamak. The comparison of radioactive waste parameters shows that radioactive waste from the experimental fast fission reactor may be less hazardous than that from the experimental fusion reactor. Inclusion of the actinides would reverse this conclusion only in the long-term. Radioactive waste from the commercial fusion reactor may always be less hazardous than that from the commercial fast fission reactor, irrespective of the inclusion or exclusion of the actinides. The fusion waste would even be far less hazardous, if advanced structural materials, like silicon carbide or vanadium alloy, were employed.

Koch, M.; Kazimi, M.S.

1991-04-01T23:59:59.000Z

168

Creep and rupture behavior of a special grade Hastelloy-X in simulated HTGR helium  

SciTech Connect

Creep and rupture tests were conducted for Hastelloy-XR (a modified version of the conventional Hastelloy alloy X) at 800, 900, and 1000/sup 0/C in simulated high-temperature gas-cooled reactor helium. Creep testing machines with special control of helium chemistry were used. As a result, the scatter of creep-rupture data could be reduced, and the variability of creep-rupture behavior due to manufacturing history could be resolved. Results of metallography and carbon analysis of ruptured specimens showed that the material improved resistance to corrosion in the helium environment, and carbon intrusion during the steady-state creep stage was suppressed to a negligible level. Under refined test conditions combined with the quality controlled material, it was demonstrated that there was little significant difference between helium and air in the creep-rupture results obtained at 800 to 1000/sup 0/C up to about 10/sup 4/h. The importance of maintaining the protective function of the surface oxide film of alloys was stressed in securing reproducibility and predictability of long-time creep performance.

Kurata, Y.; Kondo, T.; Ogawa, Y.

1984-08-01T23:59:59.000Z

169

Helium, Iron and Electron Particle Transport and Energy Transport Studies on the TFTR Tokamak  

DOE R&D Accomplishments (OSTI)

Results from helium, iron, and electron transport on TFTR in L-mode and Supershot deuterium plasmas with the same toroidal field, plasma current, and neutral beam heating power are presented. They are compared to results from thermal transport analysis based on power balance. Particle diffusivities and thermal conductivities are radially hollow and larger than neoclassical values, except possibly near the magnetic axis. The ion channel dominates over the electron channel in both particle and thermal diffusion. A peaked helium profile, supported by inward convection that is stronger than predicted by neoclassical theory, is measured in the Supershot The helium profile shape is consistent with predictions from quasilinear electrostatic drift-wave theory. While the perturbative particle diffusion coefficients of all three species are similar in the Supershot, differences are found in the L-Mode. Quasilinear theory calculations of the ratios of impurity diffusivities are in good accord with measurements. Theory estimates indicate that the ion heat flux should be larger than the electron heat flux, consistent with power balance analysis. However, theoretical values of the ratio of the ion to electron heat flux can be more than a factor of three larger than experimental values. A correlation between helium diffusion and ion thermal transport is observed and has favorable implications for sustained ignition of a tokamak fusion reactor.

Synakowski, E. J.; Efthimion, P. C.; Rewoldt, G.; Stratton, B. C.; Tang, W. M.; Grek, B.; Hill, K. W.; Hulse, R. A.; Johnson, D .W.; Mansfield, D. K.; McCune, D.; Mikkelsen, D. R.; Park, H. K.; Ramsey, A. T.; Redi, M. H.; Scott, S. D.; Taylor, G.; Timberlake, J.; Zarnstorff, M. C. (Princeton Univ., NJ (United States). Plasma Physics Lab.); Kissick, M. W. (Wisconsin Univ., Madison, WI (United States))

1993-03-00T23:59:59.000Z

170

Introduction and Condensation The 2-modular characters of Fi23  

E-Print Network (OSTI)

Introduction and Condensation The 2-modular characters of Fi23 Problem, Perfidy, Tricks, and Tackling them Verification, Overview and Outlook Computing the 2-modular characters of Fi23 Max Neunhöffer23 #12;Introduction and Condensation The 2-modular characters of Fi23 Problem, Perfidy, Tricks

Neunhöffer, Max

171

Piecing together modular : understanding the benefits and limitations of modular construction methods for multifamily development  

E-Print Network (OSTI)

The primary purpose of this thesis is to explain the benefits and limitations of modular construction as it pertains to primarily wood-frame, multifamily housing in the United States. This thesis attempts to educate the ...

Cameron, Peter J. (Peter Jay)

2007-01-01T23:59:59.000Z

172

Honeywell Modular Automation System Computer Software Documentation  

SciTech Connect

This document provides a Computer Software Documentation for a new Honeywell Modular Automation System (MAS) being installed in the Plutonium Finishing Plant (PFP). This system will be used to control new thermal stabilization furnaces in HA-211 and vertical denitration calciner in HC-230C-2.

CUNNINGHAM, L.T.

1999-09-27T23:59:59.000Z

173

Creating value for the business service buyer through modularity  

Science Journals Connector (OSTI)

The present study explores how modularity makes services visible and how it enables the customers to participate in service co-creation. We review the literature on buying business services to determine the buying challenges and we define service modularity and especially concentrate on defining the attributes of a modular service offering. Theoretical framework describing the connections of the attributes and challenges in service buying is elaborated through a single case study of a modular service in a professional service firm. We argue that a modular service offering can help customers by increasing the visibility of the service offering.

Pauliina Ulkuniemi; Saara Pekkarinen

2011-01-01T23:59:59.000Z

174

Creep rupture properties of Hastelloy-X and Incoloy-800H in a simulated HTGR helium environment containing high levels of moisture  

SciTech Connect

Creep rupture tests on Incoloy-800H and Hastelloy-X have been carried out in a simulated steamcycle high-temperature gas-cooled reactor helium environment containing a high level of moisture. For the maximum test time of 16 000 h, the creep rupture behavior of Incoloy-800H in the helium environment was not significantly different from that in air. Hastelloy-X showed a slightly lower rupture life in helium in comparison with standard air tests. Surface cracks initiated at the grain boundaries penetrating surface and cavities formed at the grain boundary triple points have been identified as major fracture mechanisms in both environments. Oxidation was the only gas/metal interaction observed in the helium environment.

Lee, K.S.

1984-08-01T23:59:59.000Z

175

Helium-filled aluminum flight tubes  

NLE Websites -- All DOE Office Websites (Extended Search)

Helium-filled aluminum flight tubes. Helium-filled aluminum flight tubes. Detector housing for the CCD camera lens, mirror, and scintillator. For more information, contact Instrument Scientist: Hassina Bilheux, bilheuxhn@ornl.gov, 865.384.9630 neutrons.ornl.gov/instruments/HFIR/factsheets/Instrument-cg1d.pdf The CG-1D beam is used for neutron imaging measurements using a white beam. Apertures (with different diameters D (pinhole geometry) are used at the entrance of the helium-filled flight path to allow L/D variation from 400 to 800. L is the distance between the aperture and the detector (where the image is produced). Samples sit on a translation/ rotation stage for alignment and tomography purposes. Detectors for CG-1D include

176

Helium corona-assisted air discharge  

SciTech Connect

Operation of atmospheric discharge of electronegative gases including air at low voltages yet without consuming any inert gas will enormously promote the application of non-thermal plasmas. By taking advantage of the low onset voltage for helium corona, air discharge was successfully launched at much reduced voltages with a needle-plate system partly contained in a helium-filled glass bulb--for a needle-plate distance of 12 mm, 1.0 kV suffices. Ultraviolet emission from helium corona facilitates the discharging of air, and the discharge current manifests distinct features such as relatively broad Trichel pulses in both half periods. This design allows safe and economic implementation of atmospheric discharge of electronegative gases, which will find a broad palette of applications in surface modification, plasma medicine and gas treatment, etc.

Jiang Nan; Gao Lei; Ji Ailing; Cao Zexian [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

2011-10-15T23:59:59.000Z

177

Underground helium travels to the Earth's surface via aquifers...  

NLE Websites -- All DOE Office Websites (Extended Search)

carried to the surface with the flow of water. The only place where helium is made on Earth is underground, where deep veins of uranium and thorium give off atoms of helium as...

178

Fluid helium at conditions of giant planetary interiors  

Science Journals Connector (OSTI)

...the nonmetal-to-metal transition in fluid helium . Phys Rev Lett 98 : 190602 . 41 Ternovoi VY Filimonov AS Pyalling AA Mintsev VB Fortov VE ( 2002 ) Thermophysical properties of helium under multiple shock compression in Shock Compression of Condensed...

Lars Stixrude; Raymond Jeanloz

2008-01-01T23:59:59.000Z

179

NUCLEAR REACTORS.  

E-Print Network (OSTI)

??Nuclear reactors are devices containing fissionable material in sufficient quantity and so arranged as to be capable of maintaining a controlled, self-sustaining NUCLEAR FISSION chain (more)

Belachew, Dessalegn

2010-01-01T23:59:59.000Z

180

UCLA program in reactor studies: The ARIES tokamak reactor study  

SciTech Connect

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

Not Available

1991-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modular helium reactor" 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

Potential applications of high temperature helium  

SciTech Connect

This paper discusses the DOE MHTGR-SC program`s recent activity to improve the economics of the MHTGR without sacrificing safety performance and two potential applications of high temperature helium, the MHTGR gas turbine plant and a process heat application for methanol production from coal.

Schleicher, R.W. Jr.; Kennedy, A.J.

1992-09-01T23:59:59.000Z

182

Potential applications of high temperature helium  

SciTech Connect

This paper discusses the DOE MHTGR-SC program's recent activity to improve the economics of the MHTGR without sacrificing safety performance and two potential applications of high temperature helium, the MHTGR gas turbine plant and a process heat application for methanol production from coal.

Schleicher, R.W. Jr.; Kennedy, A.J.

1992-09-01T23:59:59.000Z

183

Modular architecture for robotics and teleoperation  

DOE Patents (OSTI)

Systems and methods for modularization and discretization of real-time robot, telerobot and teleoperation systems using passive, network based control laws. Modules consist of network one-ports and two-ports. Wave variables and position information are passed between modules. The behavior of each module is decomposed into uncoupled linear-time-invariant, and coupled, nonlinear memoryless elements and then are separately discretized.

Anderson, Robert J. (11908 Ibex Ave., N.E., Albuquerque, NM 87111)

1996-12-03T23:59:59.000Z

184

Modular test facility for HTS insert coils  

SciTech Connect

The final beam cooling stages of a Muon Collider may require DC solenoid magnets with magnetic fields in the range of 40-50 T. In this paper we will present a modular test facility developed for the purpose of investigating very high field levels with available 2G HTS superconducting materials. Performance of available conductors is presented, together with magnetic calculations and evaluation of Lorentz forces distribution on the HTS coils. Finally a test of a double pancake coil is presented.

Lombardo, V; Bartalesi, A.; Barzi, E.; Lamm, M.; Turrioni, D.; Zlobin, A.V.; /Fermilab

2009-10-01T23:59:59.000Z

185

Copper vapor laser modular packaging assembly  

DOE Patents (OSTI)

A modularized packaging arrangement for one or more copper vapor lasers and associated equipment is disclosed herein. This arrangement includes a single housing which contains the laser or lasers and all their associated equipment except power, water and neon, and means for bringing power, water, and neon which are necessary to the operation of the lasers into the container for use by the laser or lasers and their associated equipment.

Alger, Terry W. (Tracy, CA); Ault, Earl R. (Dublin, CA); Moses, Edward I. (Castro Valley, CA)

1992-01-01T23:59:59.000Z

186

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

SciTech Connect

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

Not Available

1980-06-25T23:59:59.000Z

187

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

SciTech Connect

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

Not Available

1980-03-07T23:59:59.000Z

188

Modular CHP System for Utica College: Design Specification, March 2007  

Energy.gov (U.S. Department of Energy (DOE))

This report describes a system specification for purchasing the modularized components of a cogeneration facility for assembly, shipping, and onsite operation.

189

A graphical operations interface for modular surface systems  

E-Print Network (OSTI)

This paper presents the design and implementation of algorithms for a new graphical operations interface system specifically adapted to operating modular reconfigurable articulated surface systems. Geometric models of ...

Vona, Marsette A.

190

naval reactors  

National Nuclear Security Administration (NNSA)

After operating for 34 years and training over 14,000 sailors, the Department of Energy S1C Prototype Reactor Site in Windsor, Connecticut, was returned to "green field"...

191

Combined cold compressor/ejector helium refrigerator  

DOE Patents (OSTI)

A refrigeration apparatus having an ejector operatively connected with a cold compressor to form a two-stage pumping system. This pumping system is used to lower the pressure, and thereby the temperature of a bath of boiling refrigerant (helium). The apparatus as thus arranged and operated has substantially improved operating efficiency when compared to other processes or arrangements for achieving a similar low pressure.

Brown, Donald P. (Southold, NY)

1985-01-01T23:59:59.000Z

192

Combined cold compressor/ejector helium refrigerator  

DOE Patents (OSTI)

A refrigeration apparatus having an ejector operatively connected with a cold compressor to form a two-stage pumping system. This pumping system is used to lower the pressure, and thereby the temperature of a bath of boiling refrigerant (helium). The apparatus as thus arranged and operated has substantially improved operating efficiency when compared to other processes or arrangements for achieving a similar low pressure.

Brown, D.P.

1984-06-05T23:59:59.000Z

193

Language constructs for modular parallel programs  

SciTech Connect

We describe programming language constructs that facilitate the application of modular design techniques in parallel programming. These constructs allow us to isolate resource management and processor scheduling decisions from the specification of individual modules, which can themselves encapsulate design decisions concerned with concurrence, communication, process mapping, and data distribution. This approach permits development of libraries of reusable parallel program components and the reuse of these components in different contexts. In particular, alternative mapping strategies can be explored without modifying other aspects of program logic. We describe how these constructs are incorporated in two practical parallel programming languages, PCN and Fortran M. Compilers have been developed for both languages, allowing experimentation in substantial applications.

Foster, I.

1996-03-01T23:59:59.000Z

194

Honeywell Modular Automation System Computer Software Documentation  

SciTech Connect

The purpose of this Computer Software Document (CSWD) is to provide configuration control of the Honeywell Modular Automation System (MAS) in use at the Plutonium Finishing Plant (PFP). This CSWD describes hardware and PFP developed software for control of stabilization furnaces. The Honeywell software can generate configuration reports for the developed control software. These reports are described in the following section and are attached as addendum's. This plan applies to PFP Engineering Manager, Thermal Stabilization Cognizant Engineers, and the Shift Technical Advisors responsible for the Honeywell MAS software/hardware and administration of the Honeywell System.

STUBBS, A.M.

2000-12-04T23:59:59.000Z

195

Nucleic acid amplification using modular branched primers  

DOE Patents (OSTI)

Methods and compositions expand the options for making primers for use in amplifying nucleic acid segments. The invention eliminates the step of custom synthesis of primers for Polymerase Chain Reactions (PCR). Instead of being custom-synthesized, a primer is replaced by a combination of several oligonucleotide modules selected from a pre-synthesized library. A modular combination of just a few oligonucleotides essentially mimics the performance of a conventional, custom-made primer by matching the sequence of the priming site in the template. Each oligonucleotide module has a segment that matches one of the stretches within the priming site.

Ulanovsky, Levy (Westmont, IL)

2001-01-01T23:59:59.000Z

196

Performance Evaluation for Modular, Scalable Liquid-Rack Cooling Systems in Data Centers  

E-Print Network (OSTI)

for Modular, Scalable Liquid-Rack Cooling Systems in DataFOR A MODULAR, SCALABLE LIQUID-RACK COOLING SYSTEM IN DATA3 M ODULAR LIQUID - RACK COOLING

Xu, TengFang

2009-01-01T23:59:59.000Z

197

Research reactors - an overview  

SciTech Connect

A broad overview of different types of research and type reactors is provided in this paper. Reactor designs and operating conditions are briefly described for four reactors. The reactor types described include swimming pool reactors, the High Flux Isotope Reactor, the Mark I TRIGA reactor, and the Advanced Neutron Source reactor. Emphasis in the descriptions is placed on safety-related features of the reactors. 7 refs., 7 figs., 2 tabs.

West, C.D.

1997-03-01T23:59:59.000Z

198

In situ controlled modification of the helium density in single helium-filled nanobubbles  

SciTech Connect

We demonstrate that the helium density and corresponding pressure can be modified in single nano-scale bubbles embedded in semiconductors by using the electron beam of a scanning transmission electron microscope as a multifunctional probe: the measurement probe for imaging and chemical analysis and the irradiation source to modify concomitantly the pressure in a controllable way by fine tuning of the electron beam parameters. The control of the detrapping rate is achieved by varying the experimental conditions. The underlying physical mechanisms are discussed; our experimental observations suggest that the helium detrapping from bubbles could be interpreted in terms of direct ballistic collisions, leading to the ejection of the helium atoms from the bubble.

David, M.-L., E-mail: marie-laure.david@univ-poitiers.fr; Pailloux, F. [Institut Pprime, UPR 3346 CNRS-Universit de Poitiers, SP2MI, 86962 Futuroscope-Chasseneuil cedex (France); Canadian Centre for Electron Microscopy, Mc Master University, 1280 Main Street West, Hamilton, Ontario L8S 4M1 (Canada); Alix, K.; Mauchamp, V.; Pizzagalli, L. [Institut Pprime, UPR 3346 CNRS-Universit de Poitiers, SP2MI, 86962 Futuroscope-Chasseneuil cedex (France); Couillard, M.; Botton, G. A. [Canadian Centre for Electron Microscopy, Mc Master University, 1280 Main Street West, Hamilton, Ontario L8S 4M1 (Canada); Department of Materials Science and Engineering, Mc Master University, 1280 Main Street West, Hamilton, Ontario L8S 4M1 (Canada)

2014-03-28T23:59:59.000Z

199

Fast Machine Code for Modular Multiplication Michael Scott  

E-Print Network (OSTI)

Fast Machine Code for Modular Multiplication Michael Scott School of Computer Applications Dublin, that is the calculation of a = b e mod n where for acceptable levels of security a, b, e, and n are large multiprecision will be not much larger than the number of bits in the binary representation of e. Therefore fast modular

Bernstein, Daniel

200

On -Induction, Chiral Generators and Modular Invariants for Subfactors  

E-Print Network (OSTI)

On -Induction, Chiral Generators and Modular Invariants for Subfactors Jens B¨ockenhauer and David apply -induction and, developing further some ideas of Ocneanu, we define chiral generators -Induction, Chiral Generators and Modular Invariants 43 5.1 Relating -induction to chiral generators

Kawahigashi, Yasuyuki

Note: This page contains sample records for the topic "modular helium reactor" 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

Toward Infusing Modular and Reflective Design Learning throughout the Curriculum  

E-Print Network (OSTI)

Toward Infusing Modular and Reflective Design Learning throughout the Curriculum John C. Georgas intervention that cen- ters on the widespread infusion of design learning throughout the curriculum using: An emphasis on broadly infusing design learning through the curriculum using modular design challenges

Georgas, John

202

Light Water Reactor Sustainability  

NLE Websites -- All DOE Office Websites (Extended Search)

4 Light Water Reactor Sustainability ACCOMPLISHMENTS REPORT 2014 Accomplishments Report | Light Water Reactor Sustainability 2 T he mission of the Light Water Reactor...

203

Modular Biomass Systems Could Boost Rural Areas | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Modular Biomass Systems Could Boost Rural Areas Modular Biomass Systems Could Boost Rural Areas Modular Biomass Systems Could Boost Rural Areas June 16, 2010 - 1:09pm Addthis Community Power Corporation's modular biomass systems can generate up to 100 kilowatts of energy. | Courtesy of Community Power Corporation Community Power Corporation's modular biomass systems can generate up to 100 kilowatts of energy. | Courtesy of Community Power Corporation Stephen Graff Former Writer & editor for Energy Empowers, EERE Increased ethanol production will help revitalize the rural economy and decrease America's dependence on foreign oil, but there are other ways to create opportunities in the farmlands. For Robb Walt, president of Community Power Corporation (CPC) in Littleton, Colo., one answer is community-scale, bio-energy service companies, or

204

Z-score-based modularity for community detection in networks  

E-Print Network (OSTI)

Identifying community structure in networks is an issue of particular interest in network science. The modularity introduced by Newman and Girvan [Phys. Rev. E 69, 026113 (2004)] is the most popular quality function for community detection in networks. In this study, we identify a problem in the concept of modularity and suggest a solution to overcome this problem. Specifically, we obtain a new quality function for community detection. We refer to the function as Z-modularity because it measures the Z-score of a given division with respect to the fraction of the number of edges within communities. Our theoretical analysis shows that Z-modularity mitigates the resolution limit of the original modularity in certain cases. Computational experiments using both artificial networks and well-known real-world networks demonstrate the validity and reliability of the proposed quality function.

Miyauchi, Atsushi

2015-01-01T23:59:59.000Z

205

Modular Biomass Systems Could Boost Rural Areas | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Modular Biomass Systems Could Boost Rural Areas Modular Biomass Systems Could Boost Rural Areas Modular Biomass Systems Could Boost Rural Areas June 16, 2010 - 1:09pm Addthis Community Power Corporation's modular biomass systems can generate up to 100 kilowatts of energy. | Courtesy of Community Power Corporation Community Power Corporation's modular biomass systems can generate up to 100 kilowatts of energy. | Courtesy of Community Power Corporation Stephen Graff Former Writer & editor for Energy Empowers, EERE Increased ethanol production will help revitalize the rural economy and decrease America's dependence on foreign oil, but there are other ways to create opportunities in the farmlands. For Robb Walt, president of Community Power Corporation (CPC) in Littleton, Colo., one answer is community-scale, bio-energy service companies, or

206

A Helium Isotope Perspective On The Dixie Valley, Nevada, Hydrothermal  

Open Energy Info (EERE)

Helium Isotope Perspective On The Dixie Valley, Nevada, Hydrothermal Helium Isotope Perspective On The Dixie Valley, Nevada, Hydrothermal System Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: A Helium Isotope Perspective On The Dixie Valley, Nevada, Hydrothermal System Details Activities (3) Areas (1) Regions (0) Abstract: Fluids from springs, fumaroles, and wells throughout Dixie Valley, NV were analyzed for noble gas abundances and isotopic compositions. The helium isotopic compositions of fluids produced from the Dixie Valley geothermal field range from 0.70 to 0.76 Ra, are among the highest values in the valley, and indicate that similar to 7.5% of the total helium is derived from the mantle. A lack of recent volcanics or other potential sources requires flow of mantle-derived helium up along the

207

Intelligent Control of Modular Robotic Welding Cell  

SciTech Connect

Although robotic machines are routinely used for welding, such machines do not normally incorporate intelligent capabilities. We are studying the general problem of formulating usable levels of intelligence into welding machines. From our perspective, an intelligent machine should: incorporate knowledge of the welding process, know if the process is operating correctly, know if the weld it is making is good or bad, have the ability to learn from its experience to perform welds, and be able to optimize its own performance. To this end, we are researching machine architecture, methods of knowledge representation, decision making and conflict resolution algorithms, methods of learning and optimization, human/machine interfaces, and various sensors. This paper presents work on the machine architecture and the human/machine interface specifically for a robotic, gas metal arc welding cell. Although the machine control problem is normally approached from the perspective of having a central body of control in the machine, we present a design using distributed agents. A prime goal of this work is to develop an architecture for an intelligent machine that will support a modular, plug and play standard. A secondary goal of this work is to formulate a human/machine interface that treats the human as an active agent in the modular structure.

Smartt, Herschel Bernard; Kenney, Kevin Louis; Tolle, Charles Robert

2002-04-01T23:59:59.000Z

208

INTEGRATED FISCHER TROPSCH MODULAR PROCESS MODEL  

SciTech Connect

With declining petroleum reserves, increased world demand, and unstable politics in some of the worlds richest oil producing regions, the capability for the U.S. to produce synthetic liquid fuels from domestic resources is critical to national security and economic stability. Coal, biomass and other carbonaceous materials can be converted to liquid fuels using several conversion processes. The leading candidate for large-scale conversion of coal to liquid fuels is the Fischer Tropsch (FT) process. Process configuration, component selection, and performance are interrelated and dependent on feed characteristics. This paper outlines a flexible modular approach to model an integrated FT process that utilizes a library of key component models, supporting kinetic data and materials and transport properties allowing rapid development of custom integrated plant models. The modular construction will permit rapid assessment of alternative designs and feed stocks. The modeling approach consists of three thrust areas, or strands model/module development, integration of the model elements into an end to end integrated system model, and utilization of the model for plant design. Strand 1, model/module development, entails identifying, developing, and assembling a library of codes, user blocks, and data for FT process unit operations for a custom feedstock and plant description. Strand 2, integration development, provides the framework for linking these component and subsystem models to form an integrated FT plant simulation. Strand 3, plant design, includes testing and validation of the comprehensive model and performing design evaluation analyses.

Donna Post Guillen; Richard Boardman; Anastasia M. Gribik; Rick A. Wood; Robert A. Carrington

2007-12-01T23:59:59.000Z

209

Safety approaches for high power modular laser operation  

SciTech Connect

Approximately 20 years ago, a program was initiated at the Lawrence Livermore National Laboratory (LLNL) to study the feasibility of using lasers to separate isotopes of uranium and other materials. Of particular interest has been the development of a uranium enrichment method for the production of commercial nuclear power reactor fuel to replace current more expensive methods. The Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) Program has progressed to the point where a plant-scale facility to demonstrate commercial feasibility has been built and is being tested. The U-AVLIS Program uses copper vapor lasers which pump frequency selective dye lasers to photoionize uranium vapor produced by an electron beam. The selectively ionized isotopes are electrostatically collected. The copper lasers are arranged in oscillator/amplifier chains. The current configuration consists of 12 chains, each with a nominal output of 800 W for a system output in excess of 9 kW. The system requirements are for continuous operation (24 h a day, 7 days a week) and high availability. To meet these requirements, the lasers are designed in a modular form allowing for rapid change-out of the lasers requiring maintenance. Since beginning operation in early 1985, the copper lasers have accumulated over 2 million unit hours at a >90% availability. The dye laser system provides approximately 2.5 kW average power in the visible wavelength range. This large-scale laser system has many safety considerations, including high-power laser beams, high voltage, and large quantities ({approximately}3000 gal) of ethanol dye solutions. The Laboratory`s safety policy requires that safety controls be designed into any process, equipment, or apparatus in the form of engineering controls. Administrative controls further reduce the risk to an acceptable level. Selected examples of engineering and administrative controls currently being used in the U-AVLIS Program are described.

Handren, R.T.

1993-03-01T23:59:59.000Z

210

Catalytic reactor  

DOE Patents (OSTI)

A catalytic reactor is provided with one or more reaction zones each formed of set(s) of reaction tubes containing a catalyst to promote chemical reaction within a feed stream. The reaction tubes are of helical configuration and are arranged in a substantially coaxial relationship to form a coil-like structure. Heat exchangers and steam generators can be formed by similar tube arrangements. In such manner, the reaction zone(s) and hence, the reactor is compact and the pressure drop through components is minimized. The resultant compact form has improved heat transfer characteristics and is far easier to thermally insulate than prior art compact reactor designs. Various chemical reactions are contemplated within such coil-like structures such that as steam methane reforming followed by water-gas shift. The coil-like structures can be housed within annular chambers of a cylindrical housing that also provide flow paths for various heat exchange fluids to heat and cool components.

Aaron, Timothy Mark (East Amherst, NY); Shah, Minish Mahendra (East Amherst, NY); Jibb, Richard John (Amherst, NY)

2009-03-10T23:59:59.000Z

211

Helium 4 Dimer in Two Coaxial Adjacent Nanotubes  

Science Journals Connector (OSTI)

The ground state properties of the helium 4 dimer, within the geometry defined by two adjacent nanotubes with different radii and hard core walls,...

J. Brana; S. Kili?; L. Vranje

2002-01-01T23:59:59.000Z

212

Alternatives for Helium-3 in Multiplicity Counters  

SciTech Connect

Alternatives to helium-3 are being actively pursued due to the shortage and rising costs of helium-3. For safeguards applications, there are a number of ongoing investigations to find alternatives that provide the same capability in a cost-effective manner. One of the greatest challenges is to find a comparable alternative for multiplicity counters, since they require high efficiency and short collection or die-away times. Work has been progressing on investigating three commercially available alternatives for high efficiency multiplicity counters: boron trifluoride (BF3) filled proportional tubes, boron-lined proportional tubes, and lithium fluoride with zinc sulfide coated light guides. The baseline multiplicity counter used for the investigation is the Epithermal Neutron Multiplicity Counter with 121 helium-3 filled tubes at 10 atmosphere pressure, which is a significant capability to match. The primary tool for the investigation has been modeling and simulation using the Monte Carlo N-Particle eXtended (MCNPX) radiation transport program, with experiments to validate the models. To directly calculate the coincidence rates in boron-lined (and possibly other) detectors, the MCNPX code has been enhanced to allow the existing coincidence tally to be used with energy deposition rather than neutron capture reactions. This allows boron-lined detectors to be modeled more accurately. Variations of tube number and diameter along with variations in the amount of inter-tube moderator have been conducted for the BF3 and boron-lined cases. Tube pressure was investigated for BF3, up to two atmospheres, as well as optimal boron thickness in the boron-lined tubes. The lithium fluoride was modeled as sheets of material with light guides in between, and the number and thickness of the sheets investigated. The amount of light guide, which in this case doubles as a moderator, was also optimized. The results of these modeling and simulation optimization investigations are described and results presented.

Ely, James H.; Siciliano, Edward R.; Lintereur, Azaree T.; Swinhoe, Martyn T.

2013-04-01T23:59:59.000Z

213

Kosterlitz-Thouless Transition in Helium Films  

E-Print Network (OSTI)

and the Materials Science Center, Cornell University, Ithaca, Xetv York 14853 (Received 4 November 1988) The superAuid response of helium Alms with transition temperatures ranging from 70 mK to 0.5 K has been studied using a torsional oscillator technique. A... KOSTERLITZ- THOULESS TRANSITION IN. . . 8935 =n ~Koln(R/ro)+E, (T), (1.2) where R is the size of the system and Ko =p, o( T)(A'/m) . In the above expression the core radius ro serves to cut off the divergence of the flow fields at small distances...

Agnolet, Glenn; MCQUEENEY, DF; REPPY, JD.

1989-01-01T23:59:59.000Z

214

Small modular HTGR nuclear power plant concept to meet the total energy needs of the developing nations  

SciTech Connect

In this paper, a small modular High-Temperature Gas-Cooled Reactor (HTGR) is described that can support the total energy needs of the developing nations by supplying electrical power, process steam, low-grade heat for desalination, and hydrogen production. Major features of the nuclear power plant concept, currently under development by GA Technologies Inc. (GA), are discussed with emphasis on (1) plant simplicity, (2) inherent safety, (3) ease of operation, (4) design and licensing standardization, and (5) acceptable power generation economics.

McDonald, C.F.

1983-09-26T23:59:59.000Z

215

Parametric Investigation of Brayton Cycle for High Temperature Gas-Cooled Reactor  

SciTech Connect

The Idaho National Engineering and Environmental Laboratory (INEEL) is investigating a Brayton cycle efficiency improvement on a high temperature gas-cooled reactor (HTGR) as part of Generation-IV nuclear engineering research initiative. In this project, we are investigating helium Brayton cycles for the secondary side of an indirect energy conversion system. Ultimately we will investigate the improvement of the Brayton cycle using other fluids, such as supercritical carbon dioxide. Prior to the cycle improvement study, we established a number of baseline cases for the helium indirect Brayton cycle. These cases look at both single-shaft and multiple-shaft turbomachinary. The baseline cases are based on a 250 MW thermal pebble bed HTGR. The results from this study are applicable to other reactor concepts such as a very high temperature gas-cooled reactor (VHTR), fast gas-cooled reactor (FGR), supercritical water reactor (SWR), and others. In this study, we are using the HYSYS computer code for optimization of the helium Brayton cycle. Besides the HYSYS process optimization, we performed parametric study to see the effect of important parameters on the cycle efficiency. For these parametric calculations, we use a cycle efficiency model that was developed based on the Visual Basic computer language. As a part of this study we are currently investigated single-shaft vs. multiple shaft arrangement for cycle efficiency and comparison, which will be published in the next paper.The ultimate goal of this study is to use supercritical carbon dioxide for the HTGR power conversion loop in order to improve the cycle efficiency to values great than that of the helium Brayton cycle. This paper includes preliminary calculations of the steady state overall Brayton cycle efficiency based on the pebble bed reactor reference design (helium used as the working fluid) and compares those results with an initial calculation of a CO2 Brayton cycle.

Chang Oh

2004-07-01T23:59:59.000Z

216

Dynamics on modular networks with heterogeneous correlations  

SciTech Connect

We develop a new ensemble of modular random graphs in which degree-degree correlations can be different in each module, and the inter-module connections are defined by the joint degree-degree distribution of nodes for each pair of modules. We present an analytical approach that allows one to analyze several types of binary dynamics operating on such networks, and we illustrate our approach using bond percolation, site percolation, and the Watts threshold model. The new network ensemble generalizes existing models (e.g., the well-known configuration model and Lancichinetti-Fortunato-Radicchi networks) by allowing a heterogeneous distribution of degree-degree correlations across modules, which is important for the consideration of nonidentical interacting networks.

Melnik, Sergey [MACSI, Department of Mathematics and Statistics, University of Limerick (Ireland) [MACSI, Department of Mathematics and Statistics, University of Limerick (Ireland); Oxford Centre for Industrial and Applied Mathematics, Mathematical Institute, University of Oxford, Oxford OX2 6GG (United Kingdom); CABDyN Complexity Centre, University of Oxford, Oxford OX1 1HP (United Kingdom); Porter, Mason A. [Oxford Centre for Industrial and Applied Mathematics, Mathematical Institute, University of Oxford, Oxford OX2 6GG (United Kingdom) [Oxford Centre for Industrial and Applied Mathematics, Mathematical Institute, University of Oxford, Oxford OX2 6GG (United Kingdom); CABDyN Complexity Centre, University of Oxford, Oxford OX1 1HP (United Kingdom); Mucha, Peter J. [Department of Mathematics, Carolina Center for Interdisciplinary Applied Mathematics, University of North Carolina, Chapel Hill, North Carolina 27599-3250 (United States) [Department of Mathematics, Carolina Center for Interdisciplinary Applied Mathematics, University of North Carolina, Chapel Hill, North Carolina 27599-3250 (United States); Institute for Advanced Materials, Nanoscience and Technology, University of North Carolina, Chapel Hill, North Carolina 27599-3216 (United States); Gleeson, James P. [MACSI, Department of Mathematics and Statistics, University of Limerick (Ireland)] [MACSI, Department of Mathematics and Statistics, University of Limerick (Ireland)

2014-06-15T23:59:59.000Z

217

Honeywell modular automation system computer software documentation  

SciTech Connect

The purpose of this Computer Software Document (CSWD) is to provide configuration control of the Honeywell Modular Automation System (MAS) in use at the Plutonium Finishing Plant (PFP). The Honeywell MAS is used to control the thermal stabilization furnaces in glovebox HA-211. The PFP developed software is being updated to reflect the Polycube Processing and Unwashed Salt Thermal Stabilization program addition. The polycube processing program was installed per HNF-FMP-02-11162-R2. The functional test of the program was performed in JCS work package 22-02-1031, The unwashed salt item program was installed per HNF-FMP-03-16577-RO. The functional test of the program completed in JCS work package 22-03-00654.

STUBBS, A.M.

2003-07-02T23:59:59.000Z

218

Honeywell Modular Automation System Acceptance Test Procedure  

SciTech Connect

The purpose of this Acceptance Test Procedure (ATP) is to verify the operability of the three new furnaces as controlled by the new Honeywell Modular Automation System (MAS). The Honeywell MAS is being installed in PFP to control the three thermal stabilization furnaces in glovebox HA-211. The ATP provides instructions for testing the configuration of the Honeywell MAS at the Plutonium Finishing Plant(PFP). The test will be a field test of the analog inputs, analog outputs, and software interlocks. The interlock test will check the digital input and outputs. Field equipment will not be connected forth is test. Simulated signals will be used to test thermocouple, limit switch, and vacuum pump inputs to the PLUMAS.

STUBBS, A.M.

1999-09-21T23:59:59.000Z

219

Modular, multi-level groundwater sampler  

DOE Patents (OSTI)

Apparatus for taking a multiple of samples of groundwater or pressure measurements from a well simultaneously. The apparatus comprises a series of chambers arranged in an axial array, each of which is dimensioned to fit into a perforated well casing and leave a small gap between the well casing and the exterior of the chamber. Seals at each end of the container define the limits to the axial portion of the well to be sampled. A submersible pump in each chamber pumps the groundwater that passes through the well casing perforations into the gap from the gap to the surface for analysis. The power lines and hoses for the chambers farther down the array pass through each chamber above them in the array. The seals are solid, water-proof, non-reactive, resilient disks supported to engage the inside surface of the well casing. Because of the modular design, the apparatus provides flexibility for use in a variety of well configurations.

Nichols, Ralph L. (812 Plantation Point Dr., N. Augusta, SC 29841); Widdowson, Mark A. (4204 Havana Ct., Columbia, SC 29206); Mullinex, Harry (10 Cardross La., Columbia, SC 29209); Orne, William H. (12 Martha Ct., Sumter, SC 29150); Looney, Brian B. (1135 Ridgemont Dr., Aiken, SC 29803)

1994-01-01T23:59:59.000Z

220

Kahler stabilized, modular invariant heterotic string models  

SciTech Connect

We review the theory and phenomenology of effective supergravity theories based on orbifold compactifications of the weakly-coupled heterotic string. In particular, we consider theories in which the four-dimensional theory displays target space modular invariance and where the dilatonic mode undergoes Kahler stabilization. A self-contained exposition of effective Lagrangian approaches to gaugino condensation and heterotic string theory is presented, leading to the development of the models of Bintruy, Gaillard and Wu. Various aspects of the phenomenology of this class of models are considered. These include issues of supersymmetry breaking and superpartner spectra, the role of anomalous U(1) factors, issues of flavor and R-parity conservation, collider signatures, axion physics, and early universe cosmology. For the vast majority of phenomenological considerations the theories reviewed here compare quite favorably to other string-derived models in the literature. Theoretical objections to the framework and directions for further research are identified and discussed.

Gaillard, Mary K.; Gaillard, Mary K.; Nelson, Brent D.

2007-03-19T23:59:59.000Z

Note: This page contains sample records for the topic "modular helium reactor" 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

Focal plane array with modular pixel array components for scalability  

DOE Patents (OSTI)

A modular, scalable focal plane array is provided as an array of integrated circuit dice, wherein each die includes a given amount of modular pixel array circuitry. The array of dice effectively multiplies the amount of modular pixel array circuitry to produce a larger pixel array without increasing die size. Desired pixel pitch across the enlarged pixel array is preserved by forming die stacks with each pixel array circuitry die stacked on a separate die that contains the corresponding signal processing circuitry. Techniques for die stack interconnections and die stack placement are implemented to ensure that the desired pixel pitch is preserved across the enlarged pixel array.

Kay, Randolph R; Campbell, David V; Shinde, Subhash L; Rienstra, Jeffrey L; Serkland, Darwin K; Holmes, Michael L

2014-12-09T23:59:59.000Z

222

High temperature gas cooled reactor steam-methane reformer design  

SciTech Connect

The concept of the long distance transportation of process heat energy from a High Temperature Gas Cooled Reactor (HTGR) heat source, based on the steam-methane reforming reaction, is being evaluated by the Department of Energy as an energy source/application for use early in the 21st century. This paper summaries the design of a helium heated steam reformer utilized in conjunction with an intermediate loop, 850/degree/C reactor outlet temperature, HTGR process heat plant concept. This paper also discusses various design considerations leading to the mechanical design features, the thermochemical performance, the materials selection and the structural design analysis. 12 refs.

Impellezzeri, J.R.; Drendel, D.B.; Odegaard, T.K.

1981-01-01T23:59:59.000Z

223

A thermodynamic study of waste heat recovery from GT-MHR using organic Rankine cycles  

Science Journals Connector (OSTI)

This paper presents an investigation on the utilization of waste heat from a gas turbine-modular helium reactor (GT-MHR) using different arrangements of organic Rankine cycles (ORCs) for power production. The con...

Mortaza Yari; S. M. S. Mahmoudi

2011-02-01T23:59:59.000Z

224

RECENT ADVANCES IN HEAT TRANSFER TO HELIUM 1  

E-Print Network (OSTI)

509 RECENT ADVANCES IN HEAT TRANSFER TO HELIUM 1 C. JOHANNES Service de Recherches Appliquées, L boiling, forced convection heat transfer. Relations between critical nucleate flux and some parameters confronted with the problem of calculating the heat transfer from the helium to the superconducting material

Paris-Sud XI, Université de

225

DIRECT EVALUATION OF THE HELIUM ABUNDANCES IN OMEGA CENTAURI  

SciTech Connect

A direct measure of the helium abundances from the near-infrared transition of He I at 1.08 {mu}m is obtained for two nearly identical red giant stars in the globular cluster Omega Centauri. One star exhibits the He I line; the line is weak or absent in the other star. Detailed non-local thermal equilibrium semi-empirical models including expansion in spherical geometry are developed to match the chromospheric H{alpha}, H{beta}, and Ca II K lines, in order to predict the helium profile and derive a helium abundance. The red giant spectra suggest a helium abundance of Y {<=} 0.22 (LEID 54064) and Y = 0.39-0.44 (LEID 54084) corresponding to a difference in the abundance {Delta}Y {>=} 0.17. Helium is enhanced in the giant star (LEID 54084) that also contains enhanced aluminum and magnesium. This direct evaluation of the helium abundances gives observational support to the theoretical conjecture that multiple populations harbor enhanced helium in addition to light elements that are products of high-temperature hydrogen burning. We demonstrate that the 1.08 {mu}m He I line can yield a helium abundance in cool stars when constraints on the semi-empirical chromospheric model are provided by other spectroscopic features.

Dupree, A. K.; Avrett, E. H., E-mail: dupree@cfa.harvard.edu, E-mail: eavrett@cfa.harvard.edu [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)

2013-08-20T23:59:59.000Z

226

A VACANCY MODEL IN SOLID HELIUM IV B. CASTAING  

E-Print Network (OSTI)

536 A VACANCY MODEL IN SOLID HELIUM IV B. CASTAING Groupe de Physique des Solides de l here a new approach to the problem of vacancies in solid Helium 4, describing them as small liquid droplets. In this model the vacancy effective mass is very small : 0.1 mHe, where mHe is the atomic mass

Boyer, Edmond

227

Double photoionization of helium with synchrotron x-rays: Proceedings  

SciTech Connect

This report contains papers on the following topics: Overview and comparison of photoionization with charged particle impact; The ratio of double to single ionization of helium: the relationship of photon and bare charged particle impact ionization; Double photoionization of helium at high energies; Compton scattering of photons from electrons bound in light elements; Electron ionization and the Compton effect in double ionization of helium; Elimination of two atomic electrons by a single energy photon; Double photoionization of helium at intermediate energies; Double Photoionization: Gauge Dependence, Coulomb Explosion; Single and Double Ionization by high energy photon impact; The effect of Compton Scattering on the double to single ionization ratio in helium; and Double ionization of He by photoionization and Compton scattering. These papers have been cataloged separately for the database.

Not Available

1994-01-01T23:59:59.000Z

228

Modular Applied General Equilibrium Tool (MAGNET) | Open Energy Information  

Open Energy Info (EERE)

Modular Applied General Equilibrium Tool (MAGNET) Modular Applied General Equilibrium Tool (MAGNET) Jump to: navigation, search Tool Summary Name: Modular Applied General Equilibrium Tool (MAGNET) Agency/Company /Organization: LEI Wageningen UR, the Netherlands Complexity/Ease of Use: Moderate Related Tools Ex Ante Appraisal Carbon-Balance Tool (EX-ACT) Climate Rapid Overview and Decision Support (C-ROADS) Simulator Partnership for Economic Policy Modeling and Policy Impact Analysis (MPIA) ... further results Find Another Tool FIND DEVELOPMENT IMPACTS ASSESSMENT TOOLS A modular global computable general equilibrium model that covers the whole economy and has been used extensively in agricultural, environmental, and trade policy analysis; builds on the GTAP model, and is the successor of LEITAP. Approach MAGNET is based on the Global Trade Analysis Project (GTAP) model and

229

DOE Hydrogen Analysis Repository: Renewable Energy Power System Modular  

NLE Websites -- All DOE Office Websites (Extended Search)

Renewable Energy Power System Modular Simulator (RPM-Sim) Renewable Energy Power System Modular Simulator (RPM-Sim) Project Summary Full Title: Renewable Energy Power System Modular Simulator (RPM-Sim) Project ID: 104 Principal Investigator: Edward Muljadi Keywords: Renewable; hybrid electric vehicles (HEV) Purpose This is a package software program developed based on a modular concept. Each module consists of a type of equipment or an element of a power system (for example, diesel-genset, wind turbine generator, village load, rotary converter, PV-inverter module, fuel cell-inverter module (developed by Prof. Hashem Nehrir, Montana State University), electrolysis module (developed by Prof. Hosein Salehfar and Prof. Mann University of North Dakota). Performer Principal Investigator: Edward Muljadi Organization: National Renewable Energy Laboratory (NREL)

230

Modularity and Commonality Research: Past Developments and Future Opportunities  

E-Print Network (OSTI)

Research on modularity and commonality has grown substantially over the past 15 years. Searching 36 journals over more than the past 35 years, I identify over 160 references in the engineering and management literature ...

Fixson, Sebastian K.

2007-04-20T23:59:59.000Z

231

Improving link failover efficiency in MANETs using modular prediction  

Science Journals Connector (OSTI)

In this paper, we present a flexible, modular architecture to combine various link state related measurements and prediction algorithms in order to accurately predict link failure in MANETs, while keeping bandwidth and energy overhead low. Our architecture ...

E. Van Den Berg; A. Cisneros; I. Hokelek; K. Parmeswaran; S. Samtani; J. Sucec; J. L. Simbol; A. Staikos; G. B. Rucker

2010-04-01T23:59:59.000Z

232

Distributed algorithms for self-disassembly in modular robots  

E-Print Network (OSTI)

We developed a modular robotic system that behaves as programmable matter. Specifically, we designed, implemented, and tested a collection of robots that, starting from an amorphous arrangement, can be assembled into ...

Gilpin, Kyle W

2006-01-01T23:59:59.000Z

233

Retroactivity, modularity, and insulation in synthetic biology circuits  

E-Print Network (OSTI)

A central concept in synthetic biology is the reuse of well-characterized modules. Modularity simplifies circuit design by allowing for the decomposition of systems into separate modules for individual construction. Complex ...

Lin, Allen

2011-01-01T23:59:59.000Z

234

Modular redundancy without voters decreases complexity of restoring organ  

Science Journals Connector (OSTI)

Fault-tolerant modules have usually been implemented through the use of static fault-masking or dynamic spare-switching. But a new class of MR (Modular Redundancy), the Responsive schemes, promises higher reliability levels and more efficient implementations ...

P. T. DeSousa; F. P. Mathur

1977-06-01T23:59:59.000Z

235

Distributed Online Learning of Central Pattern Generators in Modular Robots  

Science Journals Connector (OSTI)

In this paper we study distributed online learning of locomotion gaits for modular robots. The learning is based on a stochastic approximation method, SPSA, which optimizes the parameters of coupled oscillator...

David Johan Christensen; Alexander Sprwitz

2010-01-01T23:59:59.000Z

236

Light Water Reactors Technology Development - Nuclear Reactors  

NLE Websites -- All DOE Office Websites (Extended Search)

Light Water Reactors Light Water Reactors About Director's Welcome Organization Achievements Highlights Fact Sheets, Brochures & Other Documents Multimedia Library Visit Argonne Work with Argonne Contact us Nuclear Energy Why Nuclear Energy? Why are some people afraid of Nuclear Energy? How do nuclear reactors work? Cheaper & Safer Nuclear Energy Helping to Solve the Nuclear Waste Problem Nuclear Reactors Nuclear Reactors Early Exploration Training Reactors Basic and Applied Science Research LWR Technology Development BORAX-III lighting Arco, Idaho (Press Release) Heavy Water and Graphite Reactors Fast Reactor Technology Integral Fast Reactor Argonne Reactor Tree CP-1 70th Anniversary CP-1 70th Anniversary Argonne's Nuclear Science and Technology Legacy Argonne's Nuclear Science and Technology Legacy

237

Fuel and cladding nano-technologies based solutions for long life heat-pipe based reactors  

SciTech Connect

A novel nuclear reactor concept, unifying the fuel pipe with fuel tube functionality has been developed. The structure is a quasi-spherical modular reactor, designed for a very long life. The reactor module unifies the fuel tube with the heat pipe and a graphite beryllium reflector. It also uses a micro-hetero-structure that allows the fission products to be removed in the heat pipe flow and deposited in a getter area in the cold zone of the heat pipe, but outside the neutron flux. The reactor operates as a breed and burn reactor - it contains the fuel pipe with a variable enrichment, starting from the hot-end of the pipe, meant to assure the initial criticality, and reactor start-up followed by area with depleted uranium or thorium that get enriched during the consumption of the first part of the enriched uranium. (authors)

Popa-Simil, L. [LAVM LLC, Los Alamos (United States)

2012-07-01T23:59:59.000Z

238

On the modular curve X0(23) Rene Schoof  

E-Print Network (OSTI)

that the extension does not split over Z[ 1 23 ]. The group scheme J0(23)[2] even has irreducible featuresOn the modular curve X0(23) Ren´e Schoof Abstract. The Jacobian J0(23) of the modular curve X0(23) is a semi-stable abelian variety over Q with good reduction outside 23. It is simple. We prove that every

Schoof, René

239

A MODULAR ACTUATOR ARCHITECTURE FOR ROBOTIC APPLICATIONS  

SciTech Connect

The United States Department of Energy (DOE) Complexes perform numerous hazardous material handling operations within the confines of a glovebox. The DOE is continuing to seek more efficient and safer means of handling these materials inside gloveboxes rather than the conventional, labor-intensive method through lead lined gloves. The use of glovebox automation technology will also be critical to the DOE in its efforts to comply with its mandated ALARA principles in handling the hazardous materials associated with the cleanup process. Operations associated with materials processing in a glovebox are similar to many industrial tasks, but the unique glovebox environment and Plutonium material properties create a unique set of challenges for conventional automation machinery. Such properties include: Low to moderate levels of ionizing radiation, high abrasiveness, corrosiveness, pyrophoric tendencies, rapid dispersal and permeation of environment, diffuses quickly, and possible incompatible material interaction. The glovebox presents the following challenges: existing gloveboxes may not be readily altered or even modified at all, complex mechanical operations for maintenance and repair are difficult or impossible through gloves, failed equipment may not be removed easily or at all. If a broken piece of equipment cannot be bagged-out through a glove port (approximately 216 mm (8 1/2 inch) diameter) it must remain in place. Broken equipment obstructs further operations. If it renders the entire glovebox unusable, a significant volume of waste is generated and an expensive system must be disposed of and replaced. A moderate sized glovebox alone costs between $250,000 and $500,000 and an equipment malfunction, which penetrates the glovebox and exposes the room to Plutonium or other toxic materials, is catastrophic. In addition to the human exposure issues, cleanup can easily run into the millions of dollars. A solution to the issues described above is ARM Automation Inc.'s (ARM) modular robotic manipulator technology developed for DOE EM operations, which addresses many of the issues discussed in the previous section. This manipulator system has the capability of custom configurations, which accommodate common glovebox tasks such as materials repackaging. The modular nature and quick connects of this system simplify installations into ''hot'' boxes and any potential modifications or repair therein. In the field of automation and robotics, a very common element is one used to generate motion for precise positioning of loads. One example of such an automation component would be an individual joint within an industrial robotic manipulator. This component consists of a tightly integrated package containing an electric motor, gear train, output support bearings, position sensors, brake, servo-amplifier and communications controller. Within the context of this paper, this key building block is referred to as an actuator module. With regard to the needs of the EM, [8] and [9] have shown that while each focus area has unique requirements for robotic automation at a system or manipulator level, their requirements at the actuator level are very similar. Thereby, a modular approach to automation which utilizes a small set of versatile actuator modules can be used to construct a broad range of robotic systems and automation cells suited to EM applications. By providing a pre-engineered, pre-integrated motion system to different robotics users within the DOE, new automation systems can be more quickly created without extensive expertise in motion control or the expense of building custom equipment.

None

2001-07-01T23:59:59.000Z

240

Modular robotics overview of the `state of the art`  

SciTech Connect

The design of a robotic arm processing modular components and reconfigurable links is the general goal of a modular robotics development program. The impetus behind the pursuit of modular design is the remote engineering paradigm of improved reliability and availability provided by the ability to remotely maintain and repair a manipulator operating in a hazardous environment by removing and replacing worn or failed modules. Failed components can service off- line and away from hazardous conditions. The desire to reconfigure an arm to perform different tasks is also an important driver for the development of a modular robotic manipulator. In order to bring to fruition a truly modular manipulator, an array of technical challenges must be overcome. These range from basic mechanical and electrical design considerations such as desired kinematics, actuator types, and signal and transmission types and routings, through controls issues such as the need for control algorithms capable of stable free space and contact control, to computer and sensor design issues like consideration of the use of embedded processors and redundant sensors. This report presents a brief overview of the state of the art of technical issues relevant of modular robotic arm design. The focus is on breadth of coverage, rather than depth, in order to provide a reference frame for future development.

Kress, R.L.; Jansen, J.F.; Hamel, W.R.

1996-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "modular helium reactor" 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

Issues in acoustic field testing of quiet modular classrooms  

Science Journals Connector (OSTI)

Modular classrooms are important to American education: About 300 000 modular classrooms are currently in use by public school systems here. Good acoustical conditions for learning are no less vital for students in modular classrooms than stick?built classrooms. In an effort to promote good acoustics in modular classrooms ANSI S12 Working Group 46 is seeking to standardize acoustic field testing. Their efforts are in response to key acoustical issues of modular classrooms: Excessive noise from HVAC (heating ventilating and air conditioning) systems and poor airborne sound insulation from exterior noise sources. In a recent and notable advance an HVAC system provider reported good progress in modular HVACnoise reduction: A ducted wall mounted system was used instead of the usual free blowing system with exposed fans. HVACnoise in the unoccupied room was near the maximum 35 dB level required by ANSI S12.60. Interior noise levels were so low that efforts to confirm their values were confounded by noise contamination from exterior sources. The relatively high interior ambient noise levels were due to poor airborne sound insulation. Lessons learned from recent field testing will be discussed. Results of airborne sound insulation tests now in planning stages will be reported if available.

David Lubman; Louis C. Sutherland

2007-01-01T23:59:59.000Z

242

Scattering of Fast Neutrons by Helium  

Science Journals Connector (OSTI)

Measurements have been made of the angular distribution of helium recoils for incident neutrons of energies from 0.6 to 1.6 Mev. The distribution curves also permit estimates of the total cross section in this energy range. The results confirm the existence of a cross-section peak of about 6.810-24 cm2 around 1 Mev and indicate, under the assumption of s- and p-wave scattering only, that the peak is double. But preliminary attempts to fit the data to Bloch's detailed theory of s- and p-scattering with a split p-level have not been successful, and the sign of the postulated splitting is not established.

T. A. Hall and P. G. Koontz

1947-08-01T23:59:59.000Z

243

Continuous Photoelectric Absorption Cross Section of Helium  

Science Journals Connector (OSTI)

The continuous photoelectric absorption cross section of helium has been measured in the spectral region extending from 180 to 600 A with greater accuracy and the observations are found to agree with the calculations of Huang and Stewart and Wilkinson. A grazing incidence spectrometer with a photomultiplier was used for a single measurement at 180 A while the remaining measurements were carried out in a normal incidence spectrometer utilizing photographic techniques. Whereas in previous experiments the absorbing gas sample was allowed to fill the entire spectrometer chamber, in the current measurements the gas was confined to a small cell provided with sufficiently transparent windows. The use of an absorption cell reduces contamination and facilitates the measurement of gas pressures. The results indicate that the cross section varies from a value of 0.980.04 Mb at 180 A to a value of 7.70.3 Mb at the absorption edge located at 504 A.

D. J. Baker; Jr.; D. E. Bedo; D. H. Tomboulian

1961-12-01T23:59:59.000Z

244

Helium in the outer solar atmosphere  

Science Journals Connector (OSTI)

We construct models of the outer solar atmosphere comprising the region from the mid chromosphere and into the solar wind in order to study the force and energy balance in models with a significant helium abundance. The corona is created by dissipation of an energy flux from the Sun. The energy flux is lost as radiation from the top of the chromosphere and as gravitational and kinetic solar wind energy flux. We find that in models with significant ion heating of the extended corona most of the energy flux is lost in the solar wind. The ion temperatures are higher than the electron temperature in these models and the ?-particle temperature is much higher than the proton temperature. Roughly speaking we find that the relative ?-particle and proton fluxes are set by the degree of chromospheric mixing while the speeds are set by the details of the coronal heating process.

V. H. Hansteen; E. Leer; T. E. Holzer

1997-01-01T23:59:59.000Z

245

Helium solubility in SON68 nuclear waste glass  

SciTech Connect

Helium behavior in a sodium borosilicate glass (SON68) dedicated to the immobilization of high-level nuclear waste is examined. Two experimental approaches on nonradioactive glass specimens are implemented: pressurized helium infusion experiments and {sup 3}He ion implantation experiments. The temperature variation of helium solubility in SON68 glass was determined and analyzed with the harmonic oscillator model to determine values of the energy of interaction E(0) at the host sites (about -4000 J/mol), the vibration frequency (about 1.7 x 10{sup 11} s{sup -1}), and the density of solubility sites (2.2 x 10{sup 21} sites cm{sup -3}). The implantation experiments show that a non diffusive transport phenomenon (i.e., athermal diffusion) is involved in the material when the helium concentration exceeds 2.3 x 10{sup 21} He cm{sup -3}, and thus probably as soon as it exceeds the density of solubility sites accessible to helium in the glass. We propose that this transport mechanism could be associated with the relaxation of the stress gradient induced by the implanted helium profile, which is favored by the glass damage. Microstructural characterization by TEM and ESEM of glass specimens implanted with high helium concentrations showed a homogeneous microstructure free of bubbles, pores, or cracking at a scale of 10 nm. (authors)

Fares, Toby; Peuget, Sylvain; Bouty, Olivier; Broudic, Veronique; Maugeri, Emilio; Bes, Rene; Jegou, Christophe [CEA, DEN, DTCD SECM LMPA, F-30207 Marcoule, Bagnols Sur Cez, (France); Chamssedine, Fadel; Sauvage, Thierry [CNRS, CEMHTI, F-245071 Orleans, (France); Deschanels, Xavier [LNAR, Marcoule Inst Separat Chem, F-30207 Bagnols Sur Ceze, (France)

2012-12-15T23:59:59.000Z

246

Modular Countermine Payload for Small Robots  

SciTech Connect

Payloads for small robotic platforms have historically been designed and implemented as platform and task specific solutions. A consequence of this approach is that payloads cannot be deployed on different robotic platforms without substantial re-engineering efforts. To address this issue, we developed a modular countermine payload that is designed from the ground-up to be platform agnostic. The payload consists of the multi-mission payload controller unit (PCU) coupled with the configurable mission specific threat detection, navigation and marking payloads. The multi-mission PCU has all the common electronics to control and interface to all the payloads. It also contains the embedded processor that can be used to run the navigational and control software. The PCU has a very flexible robot interface which can be configured to interface to various robot platforms. The threat detection payload consists of a two axis sweeping arm and the detector. The navigation payload consists of several perception sensors that are used for terrain mapping, obstacle detection and navigation. Finally, the marking payload consists of a dual-color paint marking system. Through the multi-mission PCU, all these payloads are packaged in a platform agnostic way to allow deployment on multiple robotic platforms, including Talon and Packbot.

Herman Herman; Doug Few; Roelof Versteeg; Jean-Sebastien Valois; Jeff McMahill; Michael Licitra; Edward Henciak

2010-04-01T23:59:59.000Z

247

Photocatalytic reactor  

DOE Patents (OSTI)

A photocatalytic reactor is described for processing selected reactants from a fluid medium comprising at least one permeable photocatalytic membrane having a photocatalytic material. The material forms an area of chemically active sites when illuminated by light at selected wavelengths. When the fluid medium is passed through the illuminated membrane, the reactants are processed at these sites separating the processed fluid from the unprocessed fluid. A light source is provided and a light transmitting means, including an optical fiber, for transmitting light from the light source to the membrane. 4 figs.

Bischoff, B.L.; Fain, D.E.; Stockdale, J.A.D.

1999-01-19T23:59:59.000Z

248

Thermophysical Properties of Helium under Multiple Shock Compression  

Science Journals Connector (OSTI)

The results on measurements of thermodynamic properties and electrical conductivity of Helium compressed with shock wave reverberation technique up to pressure and density of 200 GPa and 1.4 g/cc are presented. The increase of the Helium conductivity up to the values of 1000 1/(Ohm?cm) was found at the densities more than 0.7 g/cc and temperature more than 15 kK. Comparison of the experimental results with different theoretical models of thermodynamic and transport properties of shocked Helium was done.

Vladimir Ya. Ternovoi; Alexander S. Filimonov; Alexei A. Pyalling; Viktor B. Mintsev; Vladimir E. Fortov

2002-01-01T23:59:59.000Z

249

L3 Milestone Use Computational Model to Design and Optimize Welding Conditions to Suppress Helium  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

L3 Milestone L3 Milestone Use Computational Model to Design and Optimize Welding Conditions to Suppress Helium Cracking during Welding June 2012 Wei Zhang and Zhili Feng, ORNL Eric Willis, EPRI Background and Objectives Today, welding is widely used for repair, maintenance and upgrade of nuclear reactor components. As a critical technology to extend the service life of nuclear power plants beyond 60 years, weld technology must be further developed to meet new challenges associated with the aging of the plants, such as control and mitigation of the detrimental effects of weld residual stresses and repair of highly irradiated materials. To meet this goal, fundamental understanding of the "welding" effect is necessary for development of new and improved welding technologies.

250

Optimum Reactor Outlet Temperatures for High Temperature Gas-Cooled Reactors Integrated with Industrial Processes  

SciTech Connect

This report summarizes the results of a temperature sensitivity study conducted to identify the optimum reactor operating temperatures for producing the heat and hydrogen required for industrial processes associated with the proposed new high temperature gas-cooled reactor. This study assumed that primary steam outputs of the reactor were delivered at 17 MPa and 540C and the helium coolant was delivered at 7 MPa at 625925C. The secondary outputs of were electricity and hydrogen. For the power generation analysis, it was assumed that the power cycle efficiency was 66% of the maximum theoretical efficiency of the Carnot thermodynamic cycle. Hydrogen was generated via the hightemperature steam electrolysis or the steam methane reforming process. The study indicates that optimum or a range of reactor outlet temperatures could be identified to further refine the process evaluations that were developed for high temperature gas-cooled reactor-integrated production of synthetic transportation fuels, ammonia, and ammonia derivatives, oil from unconventional sources, and substitute natural gas from coal.

Lee O. Nelson

2011-04-01T23:59:59.000Z

251

Hybrid adsorptive membrane reactor  

DOE Patents (OSTI)

A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

Tsotsis, Theodore T. (Huntington Beach, CA); Sahimi, Muhammad (Altadena, CA); Fayyaz-Najafi, Babak (Richmond, CA); Harale, Aadesh (Los Angeles, CA); Park, Byoung-Gi (Yeosu, KR); Liu, Paul K. T. (Lafayette Hill, PA)

2011-03-01T23:59:59.000Z

252

Worldwide advanced nuclear power reactors with passive and inherent safety: What, why, how, and who  

SciTech Connect

The political controversy over nuclear power, the accidents at Three Mile Island (TMI) and Chernobyl, international competition, concerns about the carbon dioxide greenhouse effect and technical breakthroughs have resulted in a segment of the nuclear industry examining power reactor concepts with PRIME safety characteristics. PRIME is an acronym for Passive safety, Resilience, Inherent safety, Malevolence resistance, and Extended time after initiation of an accident for external help. The basic ideal of PRIME is to develop power reactors in which operator error, internal sabotage, or external assault do not cause a significant release of radioactivity to the environment. Several PRIME reactor concepts are being considered. In each case, an existing, proven power reactor technology is combined with radical innovations in selected plant components and in the safety philosophy. The Process Inherent Ultimate Safety (PIUS) reactor is a modified pressurized-water reactor, the Modular High Temperature Gas-Cooled Reactor (MHTGR) is a modified gas-cooled reactor, and the Advanced CANDU Project is a modified heavy-water reactor. In addition to the reactor concepts, there is parallel work on super containments. The objective is the development of a passive box'' that can contain radioactivity in the event of any type of accident. This report briefly examines: why a segment of the nuclear power community is taking this new direction, how it differs from earlier directions, and what technical options are being considered. A more detailed description of which countries and reactor vendors have undertaken activities follows. 41 refs.

Forsberg, C.W.; Reich, W.J.

1991-09-01T23:59:59.000Z

253

SRS upgrades helium recovery system | National Nuclear Security  

NLE Websites -- All DOE Office Websites (Extended Search)

upgrades helium recovery system | National Nuclear Security upgrades helium recovery system | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Continuing Management Reform Countering Nuclear Terrorism About Us Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Media Room Congressional Testimony Fact Sheets Newsletters Press Releases Speeches Events Social Media Video Gallery Photo Gallery NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog Home > NNSA Blog > SRS upgrades helium recovery system SRS upgrades helium recovery system Posted By Office of Public Affairs Savannah River Site (SRS) Tritium Programs recently completed a project to design, build and relocate a new system for separating and capturing

254

Regional And Local Trends In Helium Isotopes, Basin And Range...  

Open Energy Info (EERE)

Pathways Abstract Fluids from the western margin of the Basin and Range have helium isotope ratios as high as 6-7 Ra, indicating a strong mantle melt influence and consistent...

255

Heat Transfer in Liquid Helium below 1 degrees K  

Science Journals Connector (OSTI)

...September 1955 research-article Heat Transfer in Liquid Helium below 1 degrees...is proportional to the specific heat and the diameter of the specimen. Thus the sole mechanism of heat transfer appears to be by phonons which...

1955-01-01T23:59:59.000Z

256

Helium Pumping Wall for a Liquid Lithium Tokamak Richard Majeski...  

NLE Websites -- All DOE Office Websites (Extended Search)

Helium Pumping Wall for a Liquid Lithium Tokamak Richard Majeski This invention is designed to be a subsystem of a device, a tokamak with walls or plasma facing components of...

257

A Helium Isotope Perspective On The Dixie Valley, Nevada, Hydrothermal...  

Open Energy Info (EERE)

gas abundances and isotopic compositions. The helium isotopic compositions of fluids produced from the Dixie Valley geothermal field range from 0.70 to 0.76 Ra, are among the...

258

Development of High Expansion Ratio Helium Turbo Expander  

Science Journals Connector (OSTI)

The authors developed a high expansion ratio radial inflow turbine for a helium liquefier of 100 L/h capacity for use with a 70 MW superconductive generator. The following results were obtained from this devel...

N. Ino; A. Machida; K. Ttsugawa; Y. Arai; M. Matsuki

1991-01-01T23:59:59.000Z

259

Creep properties of Hastelloy-X in impure helium environments  

SciTech Connect

In impure helium environments, Hastelloy-X is susceptible to carburization and oxidation. These effects are investigated separately, and are related to the creep behavior of the alloy. Experiments were carried out at 900/sup 0/C in both helium and air. Carburization resulted in a slight increase of the creep strength up to the onset of the tertial creep. Suppression of the creep crack growth by oxidation was confirmed using notched plate specimens of Inconel alloy 600 and Hastelloy-X. Although the difference of creep strength in air and in helium was very small and considered to be inclusive in the usual scatter, a pessimistic ratio of rupture stress in helium to that in air was estimated to be 0.9.

Nakanishi, T.; Kawakami, H.

1984-08-01T23:59:59.000Z

260

Mantle Helium And Carbon Isotopes In Separation Creek Geothermal...  

Open Energy Info (EERE)

we present the helium and carbon isotope results from the initial study of a fluid chemistry-monitoring program started in the summer of 2001 near the South Sister volcano in...

Note: This page contains sample records for the topic "modular helium reactor" 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

Mantle Helium And Carbon Isotopes In Separation Creek Geothermal Springs,  

Open Energy Info (EERE)

Mantle Helium And Carbon Isotopes In Separation Creek Geothermal Springs, Mantle Helium And Carbon Isotopes In Separation Creek Geothermal Springs, Three Sisters Area, Central Oregon- Evidence For Renewed Volcanic Activity Or A Long Term Steady State System(Question) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Paper: Mantle Helium And Carbon Isotopes In Separation Creek Geothermal Springs, Three Sisters Area, Central Oregon- Evidence For Renewed Volcanic Activity Or A Long Term Steady State System(Question) Details Activities (1) Areas (1) Regions (0) Abstract: Here we present the helium and carbon isotope results from the initial study of a fluid chemistry-monitoring program started in the summer of 2001 near the South Sister volcano in central Oregon. The Separation Creek area which is several miles due west of the volcano is the locus of

262

GEN-IV Reactors  

Science Journals Connector (OSTI)

Generation-IV reactors are a set of nuclear reactors currently being developed under international collaborations targeting ... economics, proliferation resistance, and physical protection of nuclear energy. Nuclear

Taek K. Kim

2013-01-01T23:59:59.000Z

263

The Netherlands Reactor Centre  

Science Journals Connector (OSTI)

... Two illustrated brochures in English have recently J. been issued by the Netherlands Reactor Centre ( ... Centre (Reactor Centrum Nederland). The first* gives a general survey of the ...

S. WEINTROUB

1964-04-04T23:59:59.000Z

264

A New Wide Range Equation of State for Helium-4  

E-Print Network (OSTI)

A NEW WIDE RANGE EQUATION OF STATE FOR HELIUM-4 A Dissertation by DIEGO ORLANDO ORTIZ VEGA Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR... Copyright 2013Diego Orlando Ortiz Vega ii ABSTRACT A multiparametric and fundamental equation of state is presented for the fluid thermodynamic properties of helium. The equation is valid for temperatures from the ?- line (~2.17 K) to 1500 K...

Ortiz Vega, Diego O

2013-08-01T23:59:59.000Z

265

Process Options for Nominal 2-K Helium Refrigeration System Designs  

SciTech Connect

Nominal 2-K helium refrigeration systems are frequently used for superconducting radio frequency and magnet string technologies used in accelerators. This paper examines the trade-offs and approximate performance of four basic types of processes used for the refrigeration of these technologies; direct vacuum pumping on a helium bath, direct vacuum pumping using full or partial refrigeration recovery, cold compression, and hybrid compression (i.e., a blend of cold and warm sub-atmospheric compression).

Peter Knudsen, Venkatarao Ganni

2012-07-01T23:59:59.000Z

266

Kernel for modular robot applications: Automatic modeling techniques  

SciTech Connect

A modular robotic system consists of standardized joint and link units that an be assembled into various kinematic configurations for different types of tasks. For the control and simulation of such a system, manual derivation of the kinematic and dynamic models, as well as the error model for kinematic calibration, require tremendous effort, because the models constantly change as the robot geometry is altered after module reconfiguration. This paper presents a frame-work to facilitate the model-generation procedure for the control and simulation of the modular robot system. A graph technique, termed kinematic graphs and realized through assembly incidence matrices (AIM), is introduced to represent the module-assembly sequence and robot geometry. The kinematics and dynamics are formulated based on a local representation of the theory of lie groups and Lie algebras. The automatic model-generation procedure starts with a given assembly graph of the modular robot. Kinematic, dynamic, and error models of the robot are then established, based on the local representations and iterative graph-traversing algorithms. This approach can be applied to a modular robot with both serial and branch-type geometries, and arbitrary degrees of freedom. Furthermore, the AIM of the robot naturally leads to solving the task-oriented optimal configuration problem in modular robots. There is no need to maintain a huge library of robot models, and the footprint of the overall software system can be reduced.

Chen, I.M.; Yeo, S.H.; Chen, G. [Nanyang Technological Univ. (Singapore). School of Mechanical and production Engineering] [Nanyang Technological Univ. (Singapore). School of Mechanical and production Engineering; Yang, G. [Gintic Inst. of Manufacturing Technology (Singapore). Automation Technology Div.] [Gintic Inst. of Manufacturing Technology (Singapore). Automation Technology Div.

1999-02-01T23:59:59.000Z

267

Changes in the mechanical properties of Hastelloy X when exposed to a typical gas-cooled reactor environment  

SciTech Connect

The helium used in a gas-cooled reactor will contain small amounts of H/sub 2/, CO, CH/sub 4/, H/sub 2/O, and N/sub 2/ which can lead to oxidation and carburization/decarburization of structural materials. Long-term creep tests were run on Hastelloy X to 30,000 h at 649 to 871/sup 0/C. It was found that extensive carburization occurred, the minimum creep rate and time to rupture were equal in air and impure helium environments, and the fracture strain was less in helium than in air. Thermal exposure in the temperature range of 538 to 871/sup 0/C resulted in the reduction of ductility in impact and tensile tests at ambient temperature, and this reduction was greater when the exposure was in impure helium rather than in air. A modified alloy with lower chromium and 2% titanium resisted carburization.

McCoy, H.E. Jr.

1981-01-01T23:59:59.000Z

268

DOE Hydrogen Analysis Repository: All Modular Industry Growth Assessment  

NLE Websites -- All DOE Office Websites (Extended Search)

All Modular Industry Growth Assessment (AMIGA) Model All Modular Industry Growth Assessment (AMIGA) Model Project Summary Full Title: All Modular Industry Growth Assessment (AMIGA) Model Project ID: 139 Principal Investigator: Donald Hanson Purpose A comprehensive economic model of energy markets, primarily used to simulate a wide range of technology and policy issues. Performer Principal Investigator: Donald Hanson Organization: Argonne National Laboratory (ANL) Address: 9700 S. Cass Ave. Argonne, IL 60439 Telephone: 630-252-5061 Email: dhanson@anl.gov Additional Performers: Peter Balash, NETL; John Marano, NETL Sponsor(s) Name: Peter Balash Organization: National Energy Technology Laboratory (NETL) Telephone: 412-386-5753 Email: Peter.Balash@NETL.DOE.GOV Period of Performance Start: January 2001 Project Description

269

Modular Robot Systems From Self-Assembly to Self-Disassembly  

E-Print Network (OSTI)

We have presented a detailed retrospective on modular robots and discussed connections between modular robots and programmable matter. This field has seen a great deal of creativity and innovation at the level of designing ...

Rus, Daniela L.

270

What exactly is Product Modularity? The answer depends on who you ask  

E-Print Network (OSTI)

'Product modularity' has recently experienced a significant increase in interest in the academic literature. While the concept of product modularity is used across a wide range of academic research areas, substantial ...

Fixson, Sebastian K.

2007-04-20T23:59:59.000Z

271

Concepts and technology development for the autonomous assembly and reconfiguration of modular space systems  

E-Print Network (OSTI)

This thesis will present concepts of modular space systems, including definitions and specific examples of how modularity has been incorporated into past and present space missions. In addition, it will present two ...

Rodgers, Lennon Patrick

2006-01-01T23:59:59.000Z

272

SunShot Initiative: Modular and Scalable Baseload Molten Salt Plant  

NLE Websites -- All DOE Office Websites (Extended Search)

Modular and Scalable Baseload Modular and Scalable Baseload Molten Salt Plant Conceptual Design and Feasibility to someone by E-mail Share SunShot Initiative: Modular and Scalable Baseload Molten Salt Plant Conceptual Design and Feasibility on Facebook Tweet about SunShot Initiative: Modular and Scalable Baseload Molten Salt Plant Conceptual Design and Feasibility on Twitter Bookmark SunShot Initiative: Modular and Scalable Baseload Molten Salt Plant Conceptual Design and Feasibility on Google Bookmark SunShot Initiative: Modular and Scalable Baseload Molten Salt Plant Conceptual Design and Feasibility on Delicious Rank SunShot Initiative: Modular and Scalable Baseload Molten Salt Plant Conceptual Design and Feasibility on Digg Find More places to share SunShot Initiative: Modular and Scalable

273

Export possibilities for small nuclear reactors  

SciTech Connect

The worldwide deployment of peaceful nuclear technology is predicated on conformance with the Nuclear Non-Proliferation Treaty of 1972. Under this international treaty, countries have traded away pursuit of nuclear weapons in exchange for access to commercial nuclear technology that could help them grow economically. Realistically, however, most nuclear technology has been beyond the capacity of the NPT developing countries to afford. Even if the capital cost of the plant is managed, the costs of the infrastructure and the operational complexity of most nuclear technology have taken it out of the hands of the nations who need it the most. Now, a new class of small sodium cooled reactors has been specifically designed to meet the electrical power, water, hydrogen and heat needs of small and remote users. These reactors feature small size, long refueling interval, no onsite fuel storage, and simplified operations. Sized in the 10 MW(e) to 50 MW(e) range these reactors are modularized for factory production and for rapid site assembly. The fuel would be <20% U-235 uranium fuel with a 30-year core life. This new reactor type more appropriately fills the needs of countries for lower power distributed systems that can fill the gap between large developed infrastructure and primitive distributed energy systems. Looking at UN Resolution 1540 and the impact of other agreements, there is a need to address the issues of nuclear security, fuel, waste, and economic/legal/political-stakeholder concerns. This paper describes the design features of this new reactor type that specifically address these issues in a manner that increases the availability of commercial nuclear technology to the developing nations of the world. (authors)

Campagna, M.S.; Hess, C.; Moor, P. [Burns and Roe Enterprises, Inc., Oradell, NJ (United States); Sawruk, W. [ABSG Consulting, Inc., Shillington, PA (United States)

2007-07-01T23:59:59.000Z

274

Modularity, quaternion-Khler spaces, and mirror symmetry  

SciTech Connect

We provide an explicit twistorial construction of quaternion-Khler manifolds obtained by deformation of c-map spaces and carrying an isometric action of the modular group SL(2,Z). The deformation is not assumed to preserve any continuous isometry and therefore this construction presents a general framework for describing NS5-brane instanton effects in string compactifications with N= 2 supersymmetry. In this context the modular invariant parametrization of twistor lines found in this work yields the complete non-perturbative mirror map between type IIA and type IIB physical fields.

Alexandrov, Sergei; Banerjee, Sibasish [Universit Montpellier 2, Laboratoire Charles Coulomb UMR 5221, F-34095 Montpellier (France)] [Universit Montpellier 2, Laboratoire Charles Coulomb UMR 5221, F-34095 Montpellier (France)

2013-10-15T23:59:59.000Z

275

The Los Alamos VXI-based modular RF control system  

SciTech Connect

This paper describes the design and implementation of the Los Alamos modular RF control system, which provides high-performance feedback and/or feedforward control of RF accelerator cavities. This is a flexible, modular control system which has been realized in the industry-standard VXI cardmodular format. A wide spectrum of system functionality can be accommodated simply by incorporating only those modules and features required for a particular application. The fundamental principles of the design approach are discussed. Details of the VXI implementation are given, including the system architecture and interfaces, performance capabilities, and available features.

Jachim, S.P.; Ziomek, C.; Natter, E.F.; Regan, A.H.; Hill, J.; Eaton, L.; Gutscher, W.D.; Curtin, M.; Denney, P.; Hansberry, E.; Brooks, T.

1993-01-01T23:59:59.000Z

276

The Los Alamos VXI-based modular RF control system  

SciTech Connect

This paper describes the design and implementation of the Los Alamos modular RF control system, which provides high-performance feedback and/or feedforward control of RF accelerator cavities. This is a flexible, modular control system which has been realized in the industry-standard VXI cardmodular format. A wide spectrum of system functionality can be accommodated simply by incorporating only those modules and features required for a particular application. The fundamental principles of the design approach are discussed. Details of the VXI implementation are given, including the system architecture and interfaces, performance capabilities, and available features.

Jachim, S.P.; Ziomek, C.; Natter, E.F.; Regan, A.H.; Hill, J.; Eaton, L.; Gutscher, W.D.; Curtin, M.; Denney, P.; Hansberry, E.; Brooks, T.

1993-06-01T23:59:59.000Z

277

Detection of significant differences between absorption spectra of neutral helium and low temperature photoionized helium plasmas  

SciTech Connect

In this work, spectral investigations of photoionized He plasmas were performed. The photoionized plasmas were created by irradiation of helium stream, with intense pulses from laser-plasma extreme ultraviolet (EUV) source. The EUV source was based on a double-stream Xe/Ne gas-puff target irradiated with 10 ns/10 J Nd:YAG laser pulses. The most intense emission from the source spanned a relatively narrow spectral region below 20 nm, however, spectrally integrated intensity at longer wavelengths was also significant. The EUV radiation was focused onto a gas stream, injected into a vacuum chamber synchronously with the EUV pulse. The long-wavelength part of the EUV radiation was used for backlighting of the photoionized plasmas to obtain absorption spectra. Both emission and absorption spectra in the EUV range were investigated. Significant differences between absorption spectra acquired for neutral helium and low temperature photoionized plasmas were demonstrated for the first time. Strong increase of intensities and spectral widths of absorption lines, together with a red shift of the K-edge, was shown.

Bartnik, A.; Wachulak, P.; Fiedorowicz, H.; Fok, T.; Jarocki, R.; Szczurek, M. [Institute of Optoelectronics, Military University of Technology, Kaliskiego 2, 00-908 Warsaw (Poland)] [Institute of Optoelectronics, Military University of Technology, Kaliskiego 2, 00-908 Warsaw (Poland)

2013-11-15T23:59:59.000Z

278

Atmospheric pressure plasma processing with microstructure electrodes and microplanar reactors  

Science Journals Connector (OSTI)

Atmospheric pressure plasmas can be generated, if the distance between the plasma generating electrodes is in the range of 100 ?m, and radio-frequencies of 13.56 or 27.12 \\{MHz\\} are applied. Such small dimensioned plasmas are only of interest for industrial plasma applications if larger areas can be processed. It will be shown that both with microstructure electrodes as with microplanar-reactor, plasma processing can be carried out for typical substrate dimensions of 100 mm and more using helium or neon for plasma generation. First experiments of plasma surface treatment of polymers and of thin film deposition on silicon will be presented. With mixtures of some percentage C2H2 in atmospheric pressure helium, diamond-like carbon films with deposition rates between 110 ?m/min can be deposited.

H. Schlemm; D. Roth

2001-01-01T23:59:59.000Z

279

Model-Based Testing for the Second Generation of Integrated Modular Avionics Christof Efkemann, Jan Peleska  

E-Print Network (OSTI)

activities regarding automated testing of Integrated Modular Avionics controllers in the European research, specialised electronics devices, many of them with cus- tom interfaces. In the Integrated Modular AvionicsModel-Based Testing for the Second Generation of Integrated Modular Avionics Christof Efkemann, Jan

Peleska, Jan - Fachbereich 3

280

Nuclear reactor  

DOE Patents (OSTI)

A nuclear reactor comprising a cylindrical pressure vessel, an elongated annular core centrally disposed within and spaced from the pressure vessel, and a plurality of ducts disposed longitudinally of the pressure vessel about the periphery thereof, said core comprising an annular active portion, an annular reflector just inside the active portion, and an annular reflector just outside the active a portion, said annular active portion comprising rectangular slab, porous fuel elements radially disposed around the inner reflector and extending the length of the active portion, wedge-shaped, porous moderator elements disposed adjacent one face of each fuel element and extending the length of the fuel element, the fuel and moderator elements being oriented so that the fuel elements face each other and the moderator elements do likewise, adjacent moderator elements being spaced to provide air inlet channels, and adjacent fuel elements being spaced to provide air outlet channels which communicate with the interior of the peripheral ducts, and means for introducing air into the air inlet channels which passes through the porous moderator elements and porous fuel elements to the outlet channel.

Thomson, Wallace B. (Severna Park, MD)

2004-03-16T23:59:59.000Z

Note: This page contains sample records for the topic "modular helium reactor" 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

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

SciTech Connect

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

Nolan, A.M.

1981-05-01T23:59:59.000Z

282

MHTGR: New production reactor summary of experience base  

SciTech Connect

Worldwide interest in the Modular High-Temperature Gas-Cooled Reactor (MHTGR) stems from the capability of the system to retain the advanced fuel and thermal performance while providing unparalleled levels of safety. The small power level of the MHTGR and its passive systems give it a margin of safety not attained by other concepts being developed for power generation. This report covers the experience base for the key nuclear system, components, and processes related to the MHTGR-NPR. 9 refs., 39 figs., 9 tabs.

Not Available

1988-03-01T23:59:59.000Z

283

David Lee, Douglas Osheroff, Superfluidity, and Helium 3  

NLE Websites -- All DOE Office Websites (Extended Search)

David Lee, Douglas Osheroff, Superfluidity, and Helium 3 David Lee, Douglas Osheroff, Superfluidity, and Helium 3 Resources with Additional Information David M. Lee and Douglas D. Osheroff received the 1996 Nobel Prize in Physics for 'their discovery of superfluidity in helium-3'. "In 1976, Lee shared with Richardson and Osheroff their earliest recognition for studies of superfluidity, the Simon Memorial Prize of the British Physical Society. The Buckley Prize of the American Physical Society followed for the trio in 1981. ... Douglas D. Osheroff Douglas D. Osheroff Courtesy AIP Emilio Segrè Visual Archives, AIP Meggers Gallery of Nobel Laureates David Lee David M. Lee Photo by Janerik Henriksson, Courtesy AIP Emilio Segrè Visual Archievs, W.F. Meggers Gallery of Nobel Laureate From 1966-67, Lee was a visiting scientist at Brookhaven National Laboratory ... ."1 His research at Cornell University includes " Low Temperature Physics: Normal and superfluid 3He, studies of the orientation of solid helium by optical birefringence, solid 3He and 4He, lambda phase diagram of 3He - 4He mixtures, quasiparticle tunneling in superconductors, magnetic resonance and ultrasound techniques, cooling by adiabatic demagnetization and the Pomeranchuk technique, spin waves in spin polarized hydrogen gas, high concentrations of hydrogen and nitrogen atons via matrix isolation by impurity-helium solids, magnetism, electron spin resonance."2

284

Coexistence of superfluid and solid helium in aerogel  

SciTech Connect

The results of recent neutron scattering studies of solid helium in silica aerogel are discussed. Previously I.V. Kalinin et al., Pis'ma Zh. Eksp. Teor. Fiz. 87 (1), 743 (2008) [JETP Lett. 87 (1), 645 (2008)], we detected the existence of a superfluid phase in solid helium at a temperature below 0.6 K and a pressure of 51 bar, although, according to the phase diagram, helium should be in the solid state under these conditions. This work is a continuation of the above studies whose main goal was to examine the detected phenomenon and to establish basic parameters of the existence of a superfluid phase. We have determined the temperature of the superfluid transition from solid to superfluid helium, T{sub C} = 1.3 K, by analyzing experimental data. The superfluid phase excitation parameters (lifetime, intensity, and energy) have a temperature dependence similar to that of bulk helium. The superfluid phase coexists with the solid phase in the entire measured temperature range from T = 0.05 K to T{sub C} and is a nonequilibrium one and disappears at T{sub C}.

Kalinin, I. V. [Institute for Physics and Power Engineering (Russian Federation); Kats, E. I.; Koza, M. [Institut Laue-Langevin (France); Lauter, V. V. [Oak Ridge National Laboratory (United States); Lauter, H. [Institut Laue-Langevin (France); Puchkov, A. V., E-mail: puchkov@ippe.r [Institute for Physics and Power Engineering (Russian Federation)

2010-08-15T23:59:59.000Z

285

Manhattan Project: Final Reactor Design and X-10, 1942-1943  

Office of Scientific and Technical Information (OSTI)

Schematic of the X-10 Graphite Reactor, Oak Ridge FINAL REACTOR DESIGN AND X-10 Schematic of the X-10 Graphite Reactor, Oak Ridge FINAL REACTOR DESIGN AND X-10 (Met Lab and Oak Ridge [Clinton], 1942-1943) Events > The Plutonium Path to the Bomb, 1942-1944 Production Reactor (Pile) Design, 1942 DuPont and Hanford, 1942 CP-1 Goes Critical, December 2, 1942 Seaborg and Plutonium Chemistry, 1942-1944 Final Reactor Design and X-10, 1942-1943 Hanford Becomes Operational, 1943-1944 Before any plutonium could be chemically separated from uranium for a bomb, however, that uranium would first have to be irradiated in a production pile. CP-1 had been a success as a scientific experiment, but the pile was built on such a small scale that recovering any significant amounts of plutonium from it was impractical. In the fall of 1942, scientists of the Met Lab had decided to build a second Fermi pile at Argonne as soon as his experiments on the first were completed and to proceed with the "Mae West" design for a helium-cooled production pile as well. When DuPont engineers assessed the Met Lab's plans in the late fall, they agreed that helium should be given first priority. They placed heavy water second and urged an all-out effort to produce more of this highly effective moderator. Bismuth and water were ranked third and fourth in DuPont's analysis. Priorities began to change when Enrico Fermi's CP-1 calculations demonstrated a higher value for the neutron reproduction factor k (for a theoretical reactor of infinite size) than anyone had anticipated. Met Lab scientists concluded that a water-cooled pile was now feasible. Crawford Greenewalt, head of the DuPont effort, continued, however, to support helium cooling.

286

Modular PM Motor Drives for Automotive Traction Applications  

SciTech Connect

This paper presents modular permanent magnet (PM) motor drives for automotive traction applications. A partially modularized drive system consisting of a single PM motor and multiple inverters is described. The motor has multiple three-phase stator winding sets and each winding set is driven with a separate three-phase inverter module. A truly modularized inverter and motor configuration based on an axial-gap PM motor is then introduced, in which identical PM motor modules are mounted on a common shaft and each motor module is powered by a separate inverter module. The advantages of the modular approach for both inverter and motor include: (1) power rating scalability--one design meets different power requirements by simply stacking an adequate number of modules, thus avoiding redesigning and reducing the development cost, (2) increased fault tolerance, and (3) easy repairing. A prototype was constructed by using two inverters and an axial-gap PM motor with two sets of three-phase stat or windings, and it is used to assist the diesel engine in a hybrid electric vehicle converted from a Chevrolet Suburban. The effect of different pulse-width-modulation strategies for both motoring and regenerative modes on current control is analyzed. Torque and regenerative control algorithms are implemented with a digital signal processor. Analytical and initial testing results are included in the paper.

Su, G.J.

2001-10-29T23:59:59.000Z

287

New Modularization Framework Transforms FAST Wind Turbine Modeling Tool  

Energy.gov (U.S. Department of Energy (DOE))

The National Renewable Energy Laboratory recently released an expanded version of its FAST wind turbine computer-aided engineering tool under a new modularization framework. The new framework will transform FAST into a powerful, robust, and flexible modeling software for wind and water power technology developers.

288

Should one always use Repeated Squaring for Modular Exponentiation?  

E-Print Network (OSTI)

squaring, which is based on representing the exponent in the standard binary numeration system. We show here that for certain applications, replacing the standard system by one based on Fibonacci numbers may, Fibonacci number system, cryptog­ raphy 1. Introduction Modular exponentiation is defined as the task

Klein Shmuel Tomi

289

A modular microfluidic architecture for integrated biochemical analysis  

E-Print Network (OSTI)

A modular microfluidic architecture for integrated biochemical analysis Kashan A. Shaikh*, Kee Suk for review November 15, 2004) Microfluidic laboratory-on-a-chip (LOC) systems based on a mod- ular (lead) at a sensitivity of 500 nM in microfluidic breadboard

Barron, Annelise E.

290

Modular Exponentiation Algorithm Analysis for Energy Consumption and Performance  

E-Print Network (OSTI)

Modular Exponentiation Algorithm Analysis for Energy Consumption and Performance Lin Zhong lzhong of their complexity, parallelism and latency. Insights are found for tradeoff between energy consumption of a tree structure. For example, Figure 1.3 shows to add 5 k-bit integers together in a tree sequence. It

Zhong, Lin

291

Development and Features EatSafe: Modular Portable Food Sensor  

E-Print Network (OSTI)

. The convenience of the EatSafe Sensor allows for this. PRONE TO FOOD-POISONING Seniors, children, pregnant womenDevelopment and Features EatSafe: Modular Portable Food Sensor ECE-Rady Design Competition FOOD INDUSTRY Every year >76 million people become sick from the consumption of contaminated food. PACKAGING

California at San Diego, University of

292

Expert assessments of the cost of light water small modular reactors  

Science Journals Connector (OSTI)

...viability of SMRs as an energy source. These include...variable and intermittent renewable power into systems...likely evolution of the energy system over the next...25-150 26 2 FBNR FURGS Brazil iPWR 72 26 3 ACP100...HTR 240 26 20 G4M Gen 4 Energy USA LMR 25 26 21 SMR-160...

Ahmed Abdulla; Ins Lima Azevedo; M. Granger Morgan

2013-01-01T23:59:59.000Z

293

Expert assessments of the cost of light water small modular reactors  

Science Journals Connector (OSTI)

...future, both lower up-front cost and new markets could yield a more attractive economic paradigm for SMR...that are designed to accelerate their market penetration. These investigations usually...monitoringEarthing equipmentDiesel and diesel control equipmentAux equipment: transformers...

Ahmed Abdulla; Ins Lima Azevedo; M. Granger Morgan

2013-01-01T23:59:59.000Z

294

Expert assessments of the cost of light water small modular reactors  

Science Journals Connector (OSTI)

...the Post-Fukushima Age. Presentation to the Nuclear Energy Standards Coordination Collaborative, July 17, 2012, Washington, DC...computers, monitoring equipment, instrumentation equipment 8) HVAC and fire fighting equipmentVentilation and air conditioning...

Ahmed Abdulla; Ins Lima Azevedo; M. Granger Morgan

2013-01-01T23:59:59.000Z

295

Expert assessments of the cost of light water small modular reactors  

Science Journals Connector (OSTI)

...nuclear plants. An even more fundamental point is that this strategy...agreed that this is one of the fundamental benefits of SMRs...monitoringEarthing equipmentDiesel and diesel control equipmentAux equipment...during constructionFuel for engines, turbines, and boilersWaste...

Ahmed Abdulla; Ins Lima Azevedo; M. Granger Morgan

2013-01-01T23:59:59.000Z

296

Design data needs modular high-temperature gas-cooled reactor. Revision 2  

SciTech Connect

The Design Data Needs (DDNs) provide summary statements for program management, of the designer`s need for experimental data to confirm or validate assumptions made in the design. These assumptions were developed using the Integrated Approach and are tabulated in the Functional Analysis Report. These assumptions were also necessary in the analyses or trade studies (A/TS) to develop selections of hardware design or design requirements. Each DDN includes statements providing traceability to the function and the associated assumption that requires the need.

NONE

1987-03-01T23:59:59.000Z

297

INEEL/EXT-01-01623 MODULAR PEBBLE-BED REACTOR PROJECT  

E-Print Network (OSTI)

of Energy Assistant Secretary for Environmental Management Under DOE Idaho Operations Office Contract DE Product Chemistry Module 17 2.2 Studies at MIT 20 2.2.1 In-Core Environment: Simulation of Core Fueling 21 3.1.2.4 Enhancements to the Geometric Modeling Capability 31 3.1.2.5 Ex-Core Radionuclide Decay 32 3

298

Expert assessments of the cost of light water small modular reactors  

Science Journals Connector (OSTI)

...computers, monitoring equipment, instrumentation equipment 8) HVAC and fire fighting equipmentVentilation and air conditioning...buildings that are not in controlled areas Both of the above include filters, heaters, coolers, fans, blowers, humidifiers, ducts...

Ahmed Abdulla; Ins Lima Azevedo; M. Granger Morgan

2013-01-01T23:59:59.000Z

299

Expert assessments of the cost of light water small modular reactors  

Science Journals Connector (OSTI)

...our questions. The specifications we developed for the...SMR [160 megawatts-thermal (MW th ), 45 MW e...from NuScale. Specifications for the...valves, piping, insulation, instrumentation...

Ahmed Abdulla; Ins Lima Azevedo; M. Granger Morgan

2013-01-01T23:59:59.000Z

300

A Carbon Dioxide Gas Turbine Direct Cycle with Partial Condensation for Nuclear Reactors  

SciTech Connect

A carbon dioxide gas turbine power generation system with a partial condensation cycle has been proposed for thermal and fast nuclear reactors, in which compression is done partly in the liquid phase and partly in the gas phase. This cycle achieves higher cycle efficiency than a He direct cycle mainly due to reduced compressor work of the liquid phase and of the carbon dioxide real gas effect, especially in the vicinity of the critical point. If this cycle is applied to a thermal reactor, efficiency of this cycle is about 55% at a reactor outlet temperature of 900 deg. C and pressure of 12.5 MPa, which is higher by about 10% than a typical helium direct gas turbine cycle plant (PBMR) at 900 deg. C and 8.4 MPa; this cycle also provides comparable cycle efficiency at the moderate core outlet temperature of 600 deg. C with that of the helium cycle at 900 deg. C. If this cycle is applied to a fast reactor, it is anticipated to be an alternative to liquid metal cooled fast reactors that can provide slightly higher cycle efficiency at the same core outlet temperature; it would eliminate safety problems, simplify the heat transport system and simplify plant maintenance. A passive decay heat removal system is realized by connecting a liquid carbon dioxide storage tank with the reactor vessel and by supplying carbon dioxide gasified from the tank to the core in case of depressurization event. (authors)

Yasuyoshi Kato; Takeshi Nitawaki; Yoshio Yoshizawa [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo, 152-8550 (Japan)

2002-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "modular helium reactor" 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

A cryogenic axial-centrifugal compressor for superfluid helium refrigeration  

E-Print Network (OSTI)

CERN's new project, the Large Hadron Collider (LHC), will use superfluid helium as coolant for its high-field superconducting magnets and therefore require large capacity refrigeration at 1.8 K. This may only be achieved by subatmospheric compression of gaseous helium at cryogenic temperature. To stimulate development of this technology, CERN has procured from industry prototype Cold Compressor Units (CCU). This unit is based on a cryogenic axial-centrifugal compressor, running on ceramic ball bearings and driven by a variable-frequency electrical motor operating under low-pressure helium at ambient temperature. The machine has been commissioned and is now in operation. After describing basic constructional features of the compressor, we report on measured performance.

Decker, L; Schustr, P; Vins, M; Brunovsky, I; Lebrun, P; Tavian, L

1997-01-01T23:59:59.000Z

302

Strong nuclear force in cold antihydrogen-helium collisions  

SciTech Connect

We calculate cross sections for elastic scattering and annihilation in antihydrogen-helium collisions at low energies. The calculations are based on the Born-Oppenheimer approximation, and incorporate the effects of the strong interaction through a scattering length approach. We find that the strong nuclear force not only causes significant annihilation, but also cannot be neglected in the elastic channel. In the zero energy limit we obtain the scattering length a=-7.69-3.80i a.u. for ground state antihydrogen-helium collisions. Annihilation is found to dominate over elastic scattering up to a temperature about 3 K. Loosely bound metastable antihydrogen-helium states are also investigated, and it is found that a number of relatively long-lived states with up to three units of angular momentum exist.

Jonsell, S. [Department of Physics, Umeaa University, SE-90187 Umeaa (Sweden); Froelich, P.; Eriksson, S. [Department of Quantum Chemistry, Box 518, Uppsala University, SE-75120 Uppsala (Sweden); Strasburger, K. [Institute of Physical and Theoretical Chemistry, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland)

2004-12-01T23:59:59.000Z

303

Fredericton, New Brunswick, 5 June 2010 CMS Summer Meeting slide 1 Modular Invariant Theory of the Cyclic Group  

E-Print Network (OSTI)

Fredericton, New Brunswick, 5 June 2010 CMS Summer Meeting ­ slide 1 Modular Invariant Theory Some Consequences Fredericton, New Brunswick, 5 June 2010 CMS Summer Meeting ­ slide 2 Modular 2010 CMS Summer Meeting ­ slide 3 #12;The Modular Group of Prime Order Modular Representation Theory

Wehlau, David

304

Modular cathode assemblies and methods of using the same for electrochemical reduction  

DOE Patents (OSTI)

Modular cathode assemblies are useable in electrolytic reduction systems and include a basket through which fluid electrolyte may pass and exchange charge with a material to be reduced in the basket. The basket can be divided into upper and lower sections to provide entry for the material. Example embodiment cathode assemblies may have any shape to permit modular placement at any position in reduction systems. Modular cathode assemblies include a cathode plate in the basket, to which unique and opposite electrical power may be supplied. Example embodiment modular cathode assemblies may have standardized electrical connectors. Modular cathode assemblies may be supported by a top plate of an electrolytic reduction system. Electrolytic oxide reduction systems are operated by positioning modular cathode and anode assemblies at desired positions, placing a material in the basket, and charging the modular assemblies to reduce the metal oxide.

Wiedmeyer, Stanley G; Barnes, Laurel A; Williamson, Mark A; Willit, James L

2014-12-02T23:59:59.000Z

305

Supercritical Helium Cooling of the LHC Beam Screens  

E-Print Network (OSTI)

The cold mass of the LHC superconducting magnets, operating in pressurised superfluid helium at 1.9 K, must be shielded from the dynamic heat loads induced by the circulating particle beams, by means of beam screens maintained at higher temperature. The beam screens are cooled between 5 and 20 K by forced flow of weakly supercritical helium, a solution which avoids two-phase flow in the long, narr ow cooling channels, but still presents a potential risk of thermohydraulic instabilities. This problem has been studied by theoretical modelling and experiments performed on a full-scale dedicated te st loop.

Hatchadourian, E; Tavian, L

1998-01-01T23:59:59.000Z

306

White Dwarfs in NGC 6791: Avoiding the Helium Flash  

E-Print Network (OSTI)

We propose that the anomalously bright white dwarf luminosity function observed in NGC 6791 (Bedin et al 2005) is the consequence of the formation of 0.5 Msun white dwarfs with Helium cores instead of Carbon cores. This may happen if mass loss during the ascent of the Red Giant Branch is strong enough to prevent a star from reaching the Helium flash. Such a model can explain the slower white dwarf cooling (relative to standard models) and fits naturally with scenarios advanced to explain Extreme Horizontal Branch stars, a population of which are also found in this cluster.

Brad Hansen

2005-07-12T23:59:59.000Z

307

Radial characterisation of the helium plasma produced by the axial injection torch (TIA) at atmospheric pressure  

Science Journals Connector (OSTI)

This work presents the radial characterisation of a helium plasma produced by the Torch Injection Axiale ... using a collisional-radiative model for helium at atmospheric pressure, the electronic density and e...

R. lvarez; A. Rodero; M. C. Quintero

2000-03-01T23:59:59.000Z

308

Date: Thursday May 23, 2013 Program: UHV Helium Ion Microscopy HR  

E-Print Network (OSTI)

Date: Thursday May 23, 2013 Program: UHV Helium Ion Microscopy HR Speakers: Gregor Hlawacek Helium selected investigations performed with the UTwente UHV-HIM in the last few years. The actual challenge, why

Twente, Universiteit

309

Effect of helium injection on diffusion dominated air ingress accidents in pebble bed reactors  

E-Print Network (OSTI)

The primary objective of this thesis was to validate the sustained counter air diffusion (SCAD) method at preventing natural circulation onset in diffusion dominated air ingress accidents. The analysis presented in this ...

Yurko, Joseph Paul

2010-01-01T23:59:59.000Z

310

Attrition reactor system  

DOE Patents (OSTI)

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

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

1993-09-28T23:59:59.000Z

311

Elementary Reactor Physics  

Science Journals Connector (OSTI)

... THERE are few subjects which have developed at the rate at which reactor physics and ... physics and reactor theory have done. This, of course, is largely due to the circumstances in ...

J. F. HILL

1962-02-10T23:59:59.000Z

312

Colliding Beam Fusion Reactors  

Science Journals Connector (OSTI)

The recirculating power for virtually all types of fusion reactors has previously been calculated [1] with the FokkerPlanck equation. The reactors involve non-Maxwellian plasmas. The calculations are ... the rec...

Norman Rostoker; Artan Qerushi; Michl Binderbauer

2003-06-01T23:59:59.000Z

313

A Basic LEGO Reactor Design for the Provision of Lunar Surface Power  

SciTech Connect

A final design has been established for a basic Lunar Evolutionary Growth-Optimized (LEGO) Reactor using current and near-term technologies. The LEGO Reactor is a modular, fast-fission, heatpipe-cooled, clustered-reactor system for lunar-surface power generation. The reactor is divided into subcritical units that can be safely launched with lunar shipments from Earth, and then emplaced directly into holes drilled into the lunar regolith to form a critical reactor assembly. The regolith would not just provide radiation shielding, but serve as neutron-reflector material as well. The reactor subunits are to be manufactured using proven and tested materials for use in radiation environments, such as uranium-dioxide fuel, stainless-steel cladding and structural support, and liquid-sodium heatpipes. The LEGO Reactor system promotes reliability, safety, and ease of manufacture and testing at the cost of an increase in launch mass per overall rated power level and a reduction in neutron economy when compared to a single-reactor system. A single unshielded LEGO Reactor subunit has an estimated mass of approximately 448 kg and provides approximately 5 kWe. The overall envelope for a single subunit with fully extended radiator panels has a height of 8.77 m and a diameter of 0.50 m. Six subunits could provide sufficient power generation throughout the initial stages of establishing a lunar outpost. Portions of the reactor may be neutronically decoupled to allow for reduced power production during unmanned periods of base operations. During later stages of lunar-base development, additional subunits may be emplaced and coupled into the existing LEGO Reactor network, subject to lunar base power demand. Improvements in reactor control methods, fuel form and matrix, shielding, as well as power conversion and heat rejection techniques can help generate an even more competitive LEGO Reactor design. Further modifications in the design could provide power generative opportunities for use on other extraterrestrial surfaces.

John Darrell Bess

2008-06-01T23:59:59.000Z

314

Burnup concept for a long-life fast reactor core using MCNPX.  

SciTech Connect

This report describes a reactor design with a burnup concept for a long-life fast reactor core that was evaluated using Monte Carlo N-Particle eXtended (MCNPX). The current trend in advanced reactor design is the concept of a small modular reactor (SMR). However, very few of the SMR designs attempt to substantially increase the lifetime of a reactor core, especially without zone loading, fuel reshuffling, or other artificial mechanisms in the core that %E2%80%9Cflatten%E2%80%9D the power profile, including non-uniform cooling, non-uniform moderation, or strategic poison placement. Historically, the limitations of computing capabilities have prevented acceptable margins in the temporal component of the spatial excess reactivity in a reactor design, due primarily to the error in burnup calculations. This research was performed as an initial scoping analysis into the concept of a long-life fast reactor. It can be shown that a long-life fast reactor concept can be modeled using MCNPX to predict burnup and neutronics behavior. The inherent characteristic of this conceptual design is to minimize the change in reactivity over the lifetime of the reactor. This allows the reactor to operate substantially longer at full power than traditional Light Water Reactors (LWRs) or other SMR designs. For the purpose of this study, a single core design was investigated: a relatively small reactor core, yielding a medium amount of power (~200 to 400 MWth). The results of this scoping analysis were successful in providing a preliminary reactor design involving metal U-235/U-238 fuel with HT-9 fuel cladding and sodium coolant at a 20% volume fraction.

Holschuh, Thomas Vernon,; Lewis, Tom Goslee,; Parma, Edward J.,

2013-02-01T23:59:59.000Z

315

Prospects for spheromak fusion reactors  

Science Journals Connector (OSTI)

The reactor study of Hagenson and Krakowski demonstrated the attractiveness of the spheromak as a compact fusion reactor, based on...

T. K. Fowler; D. D. Hua

1995-06-01T23:59:59.000Z

316

DESIGN OPTIMIZATION OF HIGH-PERFORMANCE HELIUM-COOLED DIVERTOR PLATE CONCEPT  

E-Print Network (OSTI)

DESIGN OPTIMIZATION OF HIGH-PERFORMANCE HELIUM-COOLED DIVERTOR PLATE CONCEPT X.R. Wanga , S Consulting, Fliederweg 3, 76351 Linkenheim, Germany A helium-cooled plate-type divertor design concept has of the concept in the high heat flux zone. This paper describes the design optimization of the helium

Raffray, A. René

317

Advanced Test Reactor Tour  

SciTech Connect

The Advanced Test Reactor at Idaho National Laboratory is the foremost nuclear materials test reactor in the world. This virtual tour describes the reactor, how experiments are conducted, and how spent nuclear fuel is handled and stored. For more information about INL research, visit http://www.facebook.com/idahonationallaboratory.

Miley, Don

2011-01-01T23:59:59.000Z

318

Improved vortex reactor system  

DOE Patents (OSTI)

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

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

1995-01-01T23:59:59.000Z

319

Advanced Test Reactor Tour  

ScienceCinema (OSTI)

The Advanced Test Reactor at Idaho National Laboratory is the foremost nuclear materials test reactor in the world. This virtual tour describes the reactor, how experiments are conducted, and how spent nuclear fuel is handled and stored. For more information about INL research, visit http://www.facebook.com/idahonationallaboratory.

Miley, Don

2013-05-28T23:59:59.000Z

320

Si deposition rates in a two-dimensional CVD (chemical vapor deposition) reactor and comparisons with model calculations  

SciTech Connect

Deposition rates are presented for silicon from silane in a helium carrier gas using a tubular CVD reactor with a two-dimensional flow geometry. Measured surface-temperature profiles, inlet gas velocities, total pressures, and silane/helium concentrations are reported, providing exact boundary conditions that can be used in a two-dimensional numerical CVD model. Comparisons are made between this data and two variations of a model by Coltrin, Kee, and Miller in which different empirical expressions for the silane and disilane reactive sticking coefficient are used.

Breiland, W.G.; Coltrin, M.E.

1989-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "modular helium reactor" 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

Turbulent Mixing on Helium-Accreting White Dwarfs  

E-Print Network (OSTI)

An attractive scenario for producing Type Ia supernovae (SNe Ia) is a double detonation, where detonation of an accreted helium layer triggers ignition of a C/O core. Whether or not such a mechanism can explain some or most SNe Ia depends on the properties of the helium burning, which in turn is set by the composition of the surface material. Using a combination of semi-analytic and simple numerical models, I explore when turbulent mixing due to hydrodynamic instabilities during the accretion process can mix C/O core material up into the accreted helium. Mixing is strongest at high accretion rates, large white dwarf (WD) masses, and slow spin rates. The mixing would result in subsequent helium burning that better matches the observed properties of SNe Ia. In some cases, there is considerable mixing that can lead to more than 50% C/O in the accreted layer at the time of ignition. These results will hopefully motivate future theoretical studies of such strongly mixed conditions. Mixing also has implications for...

Piro, Anthony L

2015-01-01T23:59:59.000Z

322

Heat Transfer Between Solids and Liquid Helium II  

Science Journals Connector (OSTI)

...February 1961 research-article Heat Transfer Between Solids and Liquid Helium...According to this author, the transfer of heat from the solid surface to the...least, some other mechanism of heat transfer may be involved. The Royal Society...

1961-01-01T23:59:59.000Z

323

NREL: Wind Research - New Modularization Framework Transforms FAST Wind  

NLE Websites -- All DOE Office Websites (Extended Search)

New Modularization Framework Transforms FAST Wind Turbine Modeling Tool New Modularization Framework Transforms FAST Wind Turbine Modeling Tool January 3, 2014 The old and new versions of the FAST wind turbine modeling tool are represented in this illustration by boxes. The earlier version of FAST is represented by three boxes aligned in a column on the left side of the illustration. They contain the words AeroDyn, FAST, and Hydrodyn and represent the three modules that worked together to model aerodynamics, hydrodynamics and servo-elastics. Double ended arrows between the boxes indicate interaction between these modules. A large red arrow pointed from the three boxes to a large rectangle in the middle shows how this earlier software evolved into the new FAST Framework. The large rectangular box in the middle contains the words FAST Driver. Seven smaller boxes to the right of the FAST driver represent the new modules that feed into the driver.

324

Lessons Learned During the Manufacture of the NCSX Modular Coils  

SciTech Connect

The National Compact Stellarator Experiment's (NCSX) modular coils presented a number of engineering and manufacturing challenges due to their complex shapes, requirements for high dimensional accuracy and high current density requirements due to space constraints. Being the first of their kind, these coils required the implementation of many new manufacturing and measuring techniques and procedures. This was the first time that these manufacturing techniques and methods were applied in the production of coils at the laboratory. This resulted in a steep learning curve for the first several coils. Through the effective use of procedures, tooling modifications, involvement and ownership by the manufacturing workforce, and an emphasis on safety, the assembly team was able to reduce the manufacturing times and improve upon the manufacturing methods. This paper will discuss the learning curve and steps that were taken to improve the manufacturing efficiency and reduce the manufacturing times for the modular coils without forfeiting quality.

James H. Chrzanowski,Thomas G. Meighan, Steven Raftopoulos and Lawrence Dudek and Paul J. Fogarty

2009-09-15T23:59:59.000Z

325

The Argonaut Reactor - Reactors designed/built by Argonne National  

NLE Websites -- All DOE Office Websites (Extended Search)

Achievements > Achievements > Argonne Reactors > Training Reactors About Director's Welcome Organization Achievements Highlights Fact Sheets, Brochures & Other Documents Multimedia Library Visit Argonne Work with Argonne Contact us Nuclear Energy Why Nuclear Energy? Why are some people afraid of Nuclear Energy? How do nuclear reactors work? Cheaper & Safer Nuclear Energy Helping to Solve the Nuclear Waste Problem Nuclear Reactors Nuclear Reactors Early Exploration Training Reactors Basic and Applied Science Research LWR Technology Development BORAX-III lighting Arco, Idaho (Press Release) Heavy Water and Graphite Reactors Fast Reactor Technology Integral Fast Reactor Argonne Reactor Tree CP-1 70th Anniversary CP-1 70th Anniversary Argonne's Nuclear Science and Technology Legacy

326

Reactor vessel support system  

DOE Patents (OSTI)

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

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

1982-01-01T23:59:59.000Z

327

The Benefit of Lean Techniques Interfaced with Modular Construction  

E-Print Network (OSTI)

. was to implement the Lean principles in their manufacturing process. Upon implementation of Lean in the process, there was again another noticeable increase in the quality of the product being produced, a typical result form that implementation. Additionally... the same course. Douthit 22 #2; Chapter 5: Suggestions for Additional Work Further investigation of how Lean manufacturing, Lean construction, and modular construction interface should be pursued for the sake of the construction industry in the United...

Douthit, Colin

2013-12-20T23:59:59.000Z

328

Overland Tidal Power Generation Using Modular Tidal Prism  

SciTech Connect

Naturally occurring sites with sufficient kinetic energy suitable for tidal power generation with sustained currents > 1 to 2 m/s are relatively rare. Yet sites with greater than 3 to 4 m of tidal range are relatively common around the U.S. coastline. Tidal potential does exist along the shoreline but is mostly distributed, and requires an approach which allows trapping and collection to also be conducted in a distributed manner. In this paper we examine the feasibility of generating sustainable tidal power using multiple nearshore tidal energy collection units and present the Modular Tidal Prism (MTP) basin concept. The proposed approach utilizes available tidal potential by conversion into tidal kinetic energy through cyclic expansion and drainage from shallow modular manufactured overland tidal prisms. A preliminary design and configuration of the modular tidal prism basin including inlet channel configuration and basin dimensions was developed. The unique design was shown to sustain momentum in the penstocks during flooding as well as ebbing tidal cycles. The unstructured-grid finite volume coastal ocean model (FVCOM) was used to subject the proposed design to a number of sensitivity tests and to optimize the size, shape and configuration of MTP basin for peak power generation capacity. The results show that an artificial modular basin with a reasonable footprint (? 300 acres) has the potential to generate 10 to 20 kw average energy through the operation of a small turbine located near the basin outlet. The potential of generating a total of 500 kw to 1 MW of power through a 20 to 40 MTP basin tidal power farms distributed along the coastline of Puget Sound, Washington, is explored.

Khangaonkar, Tarang; Yang, Zhaoqing; Geerlofs, Simon H.; Copping, Andrea

2010-03-01T23:59:59.000Z

329

Instructions for filling liquid Helium for the 800 MHz magnet This is a twoperson job and will require 2 x 100 liter tanks of liquid helium if filling  

E-Print Network (OSTI)

and will require 2 x 100 liter tanks of liquid helium if filling from 207 mm (41%). · Move the ladder to the side and place the helium tank to the right of the leg facing the 500 system and as close to the magnet as possible. · Cut all ties from the helium tanks · Hand tighten the homemade fitting to the vent port

Oliver, Douglas L.

330

Parametric Evaluation of Large-Scale High-Temperature Electrolysis Hydrogen Production Using Different Advanced Nuclear Reactor Heat Sources  

SciTech Connect

High Temperature Electrolysis (HTE), when coupled to an advanced nuclear reactor capable of operating at reactor outlet temperatures of 800 C to 950 C, has the potential to efficiently produce the large quantities of hydrogen needed to meet future energy and transportation needs. To evaluate the potential benefits of nuclear-driven hydrogen production, the UniSim process analysis software was used to evaluate different reactor concepts coupled to a reference HTE process design concept. The reference HTE concept included an Intermediate Heat Exchanger and intermediate helium loop to separate the reactor primary system from the HTE process loops and additional heat exchangers to transfer reactor heat from the intermediate loop to the HTE process loops. The two process loops consisted of the water/steam loop feeding the cathode side of a HTE electrolysis stack, and the sweep gas loop used to remove oxygen from the anode side. The UniSim model of the process loops included pumps to circulate the working fluids and heat exchangers to recover heat from the oxygen and hydrogen product streams to improve the overall hydrogen production efficiencies. The reference HTE process loop model was coupled to separate UniSim models developed for three different advanced reactor concepts (a high-temperature helium cooled reactor concept and two different supercritical CO2 reactor concepts). Sensitivity studies were then performed to evaluate the affect of reactor outlet temperature on the power cycle efficiency and overall hydrogen production efficiency for each of the reactor power cycles. The results of these sensitivity studies showed that overall power cycle and hydrogen production efficiencies increased with reactor outlet temperature, but the power cycles producing the highest efficiencies varied depending on the temperature range considered.

Edwin A. Harvego; Michael G. McKellar; James E. O'Brien; J. Stephen Herring

2009-09-01T23:59:59.000Z

331

Reactor water cleanup system  

DOE Patents (OSTI)

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

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

1994-01-01T23:59:59.000Z

332

Reactor water cleanup system  

DOE Patents (OSTI)

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

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

1994-12-20T23:59:59.000Z

333

Impact of nuclear irradiation on helium bubble nucleation at interfaces in liquid metals coupled to permeation through stainless steels  

E-Print Network (OSTI)

The impact of nucleating gas bubbles in the form of a dispersed gas phase on hydrogen isotope permeation at interfaces between liquid metals, like LLE, and structural materials, like stainless steel, has been studied. Liquid metal to structural material interfaces involving surfaces, may lower the nucleation barrier promoting bubble nucleation at active sites. Hence, hydrogen isotope absorption into gas bubbles modelling and control at interfaces may have a capital importance regarding design, operation and safety. He bubbles as a permeation barrier principle is analysed showing a significant impact on hydrogen isotope permeation, which may have a significant effect on liquid metal systems, e.g., tritium extraction systems. Liquid metals like LLE under nuclear irradiation in, e.g., breeding blankets of a nuclear fusion reactor would generate tritium which is to be extracted and recirculated as fuel. At the same time that tritium is bred, helium is also generated and may precipitate in the form of nano bubbles...

Fradera, Jorge

2013-01-01T23:59:59.000Z

334

A feasibility study of reactor-based deep-burn concepts.  

SciTech Connect

A systematic assessment of the General Atomics (GA) proposed Deep-Burn concept based on the Modular Helium-Cooled Reactor design (DB-MHR) has been performed. Preliminary benchmarking of deterministic physics codes was done by comparing code results to those from MONTEBURNS (MCNP-ORIGEN) calculations. Detailed fuel cycle analyses were performed in order to provide an independent evaluation of the physics and transmutation performance of the one-pass and two-pass concepts. Key performance parameters such as transuranic consumption, reactor performance, and spent fuel characteristics were analyzed. This effort has been undertaken in close collaborations with the General Atomics design team and Brookhaven National Laboratory evaluation team. The study was performed primarily for a 600 MWt reference DB-MHR design having a power density of 4.7 MW/m{sup 3}. Based on parametric and sensitivity study, it was determined that the maximum burnup (TRU consumption) can be obtained using optimum values of 200 {micro}m and 20% for the fuel kernel diameter and fuel packing fraction, respectively. These values were retained for most of the one-pass and two-pass design calculations; variation to the packing fraction was necessary for the second stage of the two-pass concept. Using a four-batch fuel management scheme for the one-pass DB-MHR core, it was possible to obtain a TRU consumption of 58% and a cycle length of 286 EFPD. By increasing the core power to 800 MWt and the power density to 6.2 MW/m{sup 3}, it was possible to increase the TRU consumption to 60%, although the cycle length decreased by {approx}64 days. The higher TRU consumption (burnup) is due to the reduction of the in-core decay of fissile Pu-241 to Am-241 relative to fission, arising from the higher power density (specific power), which made the fuel more reactivity over time. It was also found that the TRU consumption can be improved by utilizing axial fuel shuffling or by operating with lower material temperatures (colder core). Results also showed that the transmutation performance of the one-pass deep-burn concept is sensitive to the initial TRU vector, primarily because longer cooling time reduces the fissile content (Pu-241 specifically.) With a cooling time of 5 years, the TRU consumption increases to 67%, while conversely, with 20-year cooling the TRU consumption is about 58%. For the two-pass DB-MHR (TRU recycling option), a fuel packing fraction of about 30% is required in the second pass (the recycled TRU). It was found that using a heterogeneous core (homogeneous fuel element) concept, the TRU consumption is dependent on the cooling interval before the 2nd pass, again due to Pu-241 decay during the time lag between the first pass fuel discharge and the second pass fuel charge. With a cooling interval of 7 years (5 and 2 years before and after reprocessing) a TRU consumption of 55% is obtained. With an assumed ''no cooling'' interval, the TRU consumption is 63%. By using a cylindrical core to reduce neutron leakage, TRU consumption of the case with 7-year cooling interval increases to 58%. For a two-pass concept using a heterogeneous fuel element (and homogeneous core) with first and second pass volume ratio of 2:1, the TRU consumption is 62.4%. Finally, the repository loading benefits arising from the deep-burn and Inert Matrix Fuel (IMF) concepts were estimated and compared, for the same initial TRU vector. The DB-MHR concept resulted in slightly higher TRU consumption and repository loading benefit compared to the IMF concept (58.1% versus 55.1% for TRU consumption and 2.0 versus 1.6 for estimated repository loading benefit).

Kim, T. K.; Taiwo, T. A.; Hill, R. N.; Yang, W. S.

2005-09-16T23:59:59.000Z

335

E-Print Network 3.0 - assessing modular concepts Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

the modular FORTRAN... . This program simulates the engine cycle, determines basic aerodynamic parameters and ... Source: Qubec, Universit du - cole de technologie...

336

Effects of Modularity and Connectivity on OADM Deployment in Ring Networks  

Science Journals Connector (OSTI)

For a class of Optical Add/Drop Multiplexers, we empirically study the effects of port modularity and connectivity on device deployment in ring networks. Designs with greater...

Nuzman, Carl; Kumaran, Krishnan; Nithi, Nachi; Saniee, Iraj; Levy, David; Mitev, Peter

337

A modular data analysis pipeline for the discovery of novel RNA motifs.  

E-Print Network (OSTI)

??This dissertation presents a modular software pipeline that searches collections of RNA sequences for novel RNA motifs. In this case the motifs incorporate elements of (more)

Schonfeld, Justin

2006-01-01T23:59:59.000Z

338

Performance Evaluation for Modular, Scalable Cooling Systems with Hot Aisle Containment in Data Centers  

E-Print Network (OSTI)

MSE): ratio of total cooling power to cooling provided, inGenerally, total modular cooling power demand was somewhathigher server loads. The cooling power demand decreased when

Adams, Barbara J

2009-01-01T23:59:59.000Z

339

Performance Evaluation for Modular, Scalable Liquid-Rack Cooling Systems in Data Centers  

E-Print Network (OSTI)

MSE): ratio of total cooling power to cooling transported,Generally, total modular cooling power demand stabilized atrack) in this study. The cooling power demand decreased when

Xu, TengFang

2009-01-01T23:59:59.000Z

340

Review of Helium and Xenon Pure Component and Mixture Transport Properties and Recommendation of Estimating Approach for Project Prometheus (Viscosity and Thermal Conductivity)  

SciTech Connect

The selected configuration for the Project Prometheus Space Nuclear Power Plant was a direct coupling of Brayton energy conversion loop(s) to a single reactor heat source through the gas coolant/working fluid. A mixture of helium (He) and xenon (Xe) gas was assumed as the coolant/working fluid. Helium has superior thermal conductivity while xenon is added to increase the gas atomic weight to benefit turbomachinery design. Both elements have the advantage of being non-reactive. HeXe transport properties (viscosity and thermal conductivity) were needed to calculate pressure drops and heat transfer rates. HeXe mixture data are limited, necessitating the use of semi-empirical correlations to calculate mixture properties. Several approaches are available. Pure component properties are generally required in the mixture calculations. While analytical methods are available to estimate pure component properties, adequate helium and xenon pure component data are available. This paper compares the sources of pure component data and the approaches to calculate mixture properties. Calculated mixture properties are compared to the limited mixture data and approaches are recommended to calculate both pure component and mixture properties. Given the limited quantity of HeXe mixture data (all at one atmosphere), additional testing may have been required for Project Prometheus to augment the existing data and confirm the selection of mixture property calculation methods.

Haire, Melissa A.; Vargo, David D. [Bechtel Bettis, Inc., Bettis Atomic Power Laboratory, P.O. Box 79, West Mifflin, PA 15122 (United States)

2007-01-30T23:59:59.000Z

Note: This page contains sample records for the topic "modular helium reactor" 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

Evaluation of High-Temperature Alloys for Helium Gas Turbines  

Science Journals Connector (OSTI)

C. 1. Mechanical Property / Status of Metallic Materials Development for Application in Advanced High-Temperature Gas-Cooled Reactor / Material

Wolfgang Jakobeit; Jrn-Peter Pfeifer; Georg Ullrich

342

Generation -IV Reactor Concepts  

NLE Websites -- All DOE Office Websites (Extended Search)

Generation-IV Reactor Concepts Generation-IV Reactor Concepts Thomas H. Fanning Argonne National Laboratory 9700 South Cass Avenue Argonne, Illinois 60439, USA The Generation-IV International Forum (GIF) is a multi-national research and development (R&D) collaboration. The GIF pursues the development of advanced, next generation reactor technology with goals to improve: a) sustainability (effective fuel utilization and minimization of waste) b) economics (competitiveness with respect to other energy sources) c) safety and reliability (e.g., no need for offsite emergency response), and d) proliferation resistance and physical protection The GIF Technology Roadmap exercise selected six generic systems for further study: the Gas- cooled Fast Reactor (GFR), the Lead-cooled Fast Reactor (LFR), the Molten Salt Reactor (MSR),

343

Elastic Electron Scattering from Tritium and Helium-3  

DOE R&D Accomplishments (OSTI)

The mirror nuclei of tritium and helium-3 have been studied by the method of elastic electron scattering. Absolute cross sections have been measured for incident electron energies in the range 110 - 690 MeV at scattering angles lying between 40 degrees and 135 degrees in this energy range. The data have been interpreted in a straightforward manner and form factors are given for the distributions of charge and magnetic moment in the two nuclei over a range of four-momentum transfer squared 1.0 - 8.0 F{sup -2}. Model-independent radii of the charge and magnetic moment distributions are given and an attempt is made to deduce form factors describing the spatial distribution of the protons in tritium and helium-3.

Collard, H.; Hofstadter, R.; Hughes, E. B.; Johansson, A.; Yearian, M. R.; Day, R. B.; Wagner, R. T.

1964-10-00T23:59:59.000Z

344

Power Reactor Progress  

Science Journals Connector (OSTI)

Argonne kicks off EBWR; Allis-Chalmers plans power reactor using both nuclear and conventional fuels ... NUCLEAR POWER took two giant steps last week. ... Just as the first nuclear power system in the U. S. designed and built solely for the generation of electric power went into full operation at Argonne, Allis-Chalmers came up with a new twist in power reactorsa controlled recirculation boiling reactor (CRBR) using both nuclear and conventional fuels (C&EN, Feb. 18, page 7). ...

1957-02-25T23:59:59.000Z

345

Improved vortex reactor system  

DOE Patents (OSTI)

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

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

1995-05-09T23:59:59.000Z

346

Coefficients of the second viscosity in bulk liquid helium  

Science Journals Connector (OSTI)

The coefficients of the second viscosity in bulk liquid helium are evaluated explicitly as a function of temperature via interactions between the anomalous excitation spectrums. The four coefficients of the second viscosity exhibit a T-1 dependence at low temperatures (well below 0.6 K), which is due to three-phonon processes originating from the anomalous dispersion at very low momenta and temperatures.

Chung-In Um; Chul-Won Jun; Thomas F. George

1992-09-01T23:59:59.000Z

347

AEC Pushes Fusion Reactors  

Science Journals Connector (OSTI)

AEC Pushes Fusion Reactors ... Project Sherwood, as the study program is called, began in 1951-52 soon after the first successful thermonuclear explosion in the Pacific. ...

1955-10-10T23:59:59.000Z

348

Tokamak reactor first wall  

DOE Patents (OSTI)

This invention relates to an improved first wall construction for a tokamak fusion reactor vessel, or other vessels subjected to similar pressure and thermal stresses.

Creedon, R.L.; Levine, H.E.; Wong, C.; Battaglia, J.

1984-11-20T23:59:59.000Z

349

Advanced Nuclear Research Reactor  

SciTech Connect

This report describes technical modifications implemented by INVAP to improve the safety of the Research Reactors the company designs and builds.

Lolich, J.V.

2004-10-06T23:59:59.000Z

350

Mathematical modeling of a Fermilab helium liquefier coldbox  

SciTech Connect

Fermilab Central Helium Liquefier (CHL) facility is operated 24 hours-a-day to supply 4.6{degrees}K for the Fermilab Tevatron superconducting proton-antiproton collider Ring and to recover warm return gases. The centerpieces of the CHL are two independent cold boxes rated at 4000 and 5400 liters/hour with LN{sub 2} precool. These coldboxes are Claude cycle and have identical heat exchangers trains, but different turbo-expanders. The Tevatron cryogenics demand for higher helium supply from CHL was the driving force to investigate an installation of an expansion engine in place of the Joule-Thompson valve. A mathematical model was developed to describe the thermo- and gas-dynamic processes for the equipment included in the helium coldbox. The model is based on a finite element approach, opposite to a global variables approach, thus providing for higher accuracy and conversion stability. Though the coefficients used in thermo- and gas-dynamic equations are unique for a given coldbox, the general approach, the equations, the methods of computations, and most of the subroutines written in FORTRAN can be readily applied to different coldboxes. The simulation results are compared against actual operating data to demonstrate applicability of the model.

Geynisman, M.G.; Walker, R.J.

1995-12-01T23:59:59.000Z

351

Improving Indoor Environmental Quality and Energy Performance of Modular  

NLE Websites -- All DOE Office Websites (Extended Search)

Indoor Environmental Quality and Energy Performance of Modular Indoor Environmental Quality and Energy Performance of Modular Classroom HVAC Systems Title Improving Indoor Environmental Quality and Energy Performance of Modular Classroom HVAC Systems Publication Type Conference Proceedings Year of Publication 2005 Authors Apte, Michael G., Michael Spears, Chi-Ming Lai, and Derek G. Shendell Conference Name Proceedings of Sustainable Buildings 2005 Conference Pagination 1432-1437 Conference Location Tokyo, Japan, September 27-29, 2005 Abstract The factory-built relocatable classroom (RC) is a dominant force in the school facility construction industry in the United States (U.S.) and elsewhere. It is estimated that there are approximately 650,000 RCs currently occupied in the U.S., housing about 16 million students. RCs receive public attention due to complaints about poor indoor environmental quality (IEQ). Both measured data and anecdotal evidence in California have suggested excessive acoustical noise from heating, ventilation, and air conditioning (HVAC) equipment as a central factor leading to degraded IEQ. In the U.S., RCs are typically equipped with unitary exterior wall-mount HVAC systems, and interior acoustical noise due to structural and airborne transmission can reach levels of about 58dB(A) with compressor cycling, under unoccupied conditions. Due to these noise levels teachers often simply choose to turn off the HVAC, leading to inadequate ventilation, as well as poor thermal conditioning, and thus to poor indoor air quality. Elevated levels of carbon dioxide and volatile organic compounds including formaldehyde are common. We discuss the acoustic component of our efforts to develop and test energy efficient HVAC systems that address the ventilation, controls, and acoustic requirements necessary to ensure high quality indoor environments in RCs

352

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

SciTech Connect

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

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

2004-07-01T23:59:59.000Z

353

Modular airborne remote sampling and sensing system (MARSSS)  

SciTech Connect

Sandia is developing a modular airborne instrumentation system for the Environmental Protection Agency. This system will allow flexibility in the choice of instruments by standardizing mountings, power supplies and sampling modes. The objective is to make it possible to perform aerial surveys from chartered aircraft that have not been adapted in a more than superficial manner. It will also allow the experimenter to tailor his choice of instruments to the specific problem. Since the equipment will have a stand-alone capability, it can be applied to other problems such as long-term unattended use at remote locations or in toxic or otherwise hazardous environments.

Woods, R.O.

1982-04-01T23:59:59.000Z

354

The Helium-Core Mass at the Helium Flash in Low-Mass Red Giant Stars: Observations and Theory  

E-Print Network (OSTI)

The method developed by Raffelt (1990a,b,c) to estimate a possible increase in the standard values of the helium-core mass at the tip of the red giant branch, $\\Mc$, from properties of the color-magnitude diagrams of Galactic globular clusters is employed. In the present study, we revise and update Raffelt's database, including also constraints from RR Lyrae pulsation, and find that a small increase, by $\\Delta\\Mc \\approx 0.01\\pm 0.015 \\Msun$, cannot be ruled out with the present data and evolutionary models. Our new upper limits on $\\Delta\\Mc$ are less restrictive than those previously obtained by Raffelt, as are the corresponding constraints on novel astroparticle phenomena which may affect the evolution of low-mass red giants. Within the estimated uncertainties, however, the standard values of $\\Mc$ may also be acceptable. Raffelt's method does not rule out a low envelope helium abundance in globular cluster giants, though again the standard values are compatible with the available constraints. The influence of a non-solar ratio for the $\\alpha$-capture elements upon these results is also investigated. In addition, we review several aspects of the input physics employed in red giant stellar evolutionary calculations, with the purpose of evaluating possible sources of uncertainty in the value of the helium-core mass at the helium flash that is obtained from evolutionary computations, such as: heat conduction by electrons in the degenerate core; Coulomb effects upon the Equation of State; triple-$\\alpha$ reaction rates and screening factors; neutrino emission rates, both standard and enhanced by a possible non-zero magnetic moment; stellar rotation; microscopic element diffusion; and energy losses by axions and Weakly Interacting Massive Particles.

M. Catelan; J. A. de Freitas Pacheco; J. E. Horvath

1995-09-12T23:59:59.000Z

355

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....

356

Portfolio for fast reactor collaboration  

SciTech Connect

The development of the LMFBR type reactor in the United Kingdom is reviewed. Design characteristics of a commercial demonstration fast reactor are presented and compared with the Super Phenix reactor.

Rippon, S.

1981-12-01T23:59:59.000Z

357

TR-IIS-06-001 On the Satisfiability of Modular  

E-Print Network (OSTI)

TR-IIS-06-001 On the Satisfiability of Modular Arithmetic Formula Bow-Yaw Wang January 24, 2006 the Satisfiability of Modular Arithmetic Formula Bow-Yaw Wang Institute of Information Science Academia Sinica Taiwan used in the design of cryptosystems and pseudo random number generators. In the RSA public key system

Chen, Sheng-Wei

358

A FLEXIBLE, MODULAR APPROACH TO INTEGRATED SPACE EXPLORATION CAMPAIGN LOGISTICS MODELING, SIMULATION, AND ANALYSIS  

E-Print Network (OSTI)

A FLEXIBLE, MODULAR APPROACH TO INTEGRATED SPACE EXPLORATION CAMPAIGN LOGISTICS MODELING Students #12;2 A FLEXIBLE, MODULAR APPROACH TO INTEGRATED SPACE EXPLORATION CAMPAIGN LOGISTICS MODELING in Aeronautics and Astronautics #12;3 Abstract A space logistics modeling framework to support space exploration

de Weck, Olivier L.

359

Ris-M-2652 s Development ofA Two-level Modular  

E-Print Network (OSTI)

IS Risø-M-2652 · s Development ofA Two-level Modular Simulation Tool for Dysim Jan Eggert Kofoed-LEVEL MODULAR SIMULATION TOOL FOR DYSIM Jan Eggert Kofoed Abstract. In this report a simulation tool that assists the user when constructing continuous simulation models will be described. The simulation tool can

360

The rigid analytical regulator and K_2 of Drinfeld modular curves.  

E-Print Network (OSTI)

We evaluate a rigid analytical analogue of the Beilinson-Bloch-Deligne regulator on certain explicit elements in the K_2 of Drinfeld modular curves, constructed from analogues of modular units, and relate its value to special values of L-series using the Rankin-Selberg method.

Ambrus Pal

Note: This page contains sample records for the topic "modular helium reactor" 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

Modular RNA architecture revealed by computational analysis of existing pseudoknots and  

E-Print Network (OSTI)

Modular RNA architecture revealed by computational analysis of existing pseudoknots and ribosomal architecture is a hallmark of RNA structures, implying structural, and possibly functional, similar- ity among functional molecules (2­6). Modular architecture also implies similarity of substructural motifs among

Schlick, Tamar

362

High-temperature gas-cooled-reactor steam-methane reformer design  

SciTech Connect

The concept of the long distance transportation of process heat energy from a High Temperature Gas Cooled Reactor (HTGR) heat source, based on the steam reforming reaction, is currently being evaluated as an energy source/application for use early in the 21st century. The steam-methane reforming reaction is an endothermic reaction at temperatures approximately 700/sup 0/C and higher, which produces hydrogen, carbon monoxide and carbon dioxide. The heat of the reaction products can then be released, after being pumped to industrial site users, in a methanation process producing superheated steam and methane which is then returned to the reactor plant site. In this application the steam reforming reaction temperatures are produced by the heat energy from the core of the HTGR through forced convection of the primary or secondary helium circuit to the catalytic chemical reactor (steam reformer). This paper summarizes the design of a helium heated steam reformer utilized in conjunction with a 1170 MW(t) intermediate loop, 850/sup 0/C reactor outlet temperature, HTGR process heat plant concept. This paper also discusses various design considerations leading to the mechanical design features, the thermochemical performance, materials selection and the structural design analysis.

Impellezzeri, J.R.; Drendel, D.B.; Odegaard, T.K.

1981-01-20T23:59:59.000Z

363

Handbook of Reactor Physics  

Science Journals Connector (OSTI)

... THIS handbook is one volume in a series sponsored by the United States Atomic Energy Commission with ... data and reference information in the field of reactors. The volume is devoted to reactor physics and radiation shielding, the latter subject occupying approximately a quarter of the book.

PETER W. MUMMERY

1956-08-25T23:59:59.000Z

364

Fast reactor safety  

Science Journals Connector (OSTI)

... SIR, - In his article on fast reactor safety (26 July, page 270) Norman Dombey claims to introduce to non-specialists ... , page 270) Norman Dombey claims to introduce to non-specialists some features of fast reactors that are not available outside the technical literature. The non-specialist would do well ...

R.D. SMITH

1979-08-23T23:59:59.000Z

365

Instrumentation of Nuclear Reactors  

Science Journals Connector (OSTI)

... s Lecture Theatre on January 8, a symposium of papers on the instrumentation of nuclear reactors was organized, at which about five hundred members and visitors attended, including guests from ... the Institution, took the chair and introduced Sir John Cockcroft, whose lecture on "Nuclear Reactors and their Applications" provided a general background for the three specialized papers which followed. ...

1953-03-07T23:59:59.000Z

366

Nuclear Research Reactors  

Science Journals Connector (OSTI)

... their countries for the advent of nuclear power. A few countries had built large research reactors for the production of isotopes and to study the behaviour of nuclear fuel, but ... production of isotopes and to study the behaviour of nuclear fuel, but the small training reactor had not been developed. Since then, research ...

T. E. ALLIBONE

1963-07-20T23:59:59.000Z

367

Helium generation rates in isotopically tailored Fe-Cr-Ni alloys irradiated in FFTF/MOTA  

SciTech Connect

Three Fe-Cr-Ni alloys have been doped with 0.4% {sup 59}Ni for side-by-side irradiations of doped and undoped materials in order to determine the effects of fusion-relevant levels of helium production on microstructural development and mechanical properties. The alloys were irradiated in three successive cycles of the Materials Open Test Assembly (MOTA) located in the Fast Flux Test Facility (FFTF). Following irradiation, helium levels were measured by isotope dilution mass spectrometry. The highest level of helium achieved in doped alloys was 172 appm at 9.1 dpa for a helium(appm)-to-dpa ratio of 18.9. The overall pattern of predicted helium generation rates in doped and undoped alloys is in good agreement with the helium measurements.

Greenwood, L.R.; Garner, F.A. [Pacific Northwest Lab., Richland, WA (United States); Oliver, B.M. [Rockwell International Corp., Canoga Park, CA (United States). Rocketdyne Div.

1991-11-01T23:59:59.000Z

368

Production of carbon monoxide-free hydrogen and helium from a high-purity source  

DOE Patents (OSTI)

The invention provides vacuum swing adsorption processes that produce an essentially carbon monoxide-free hydrogen or helium gas stream from, respectively, a high-purity (e.g., pipeline grade) hydrogen or helium gas stream using one or two adsorber beds. By using physical adsorbents with high heats of nitrogen adsorption, intermediate heats of carbon monoxide adsorption, and low heats of hydrogen and helium adsorption, and by using vacuum purging and high feed stream pressures (e.g., pressures of as high as around 1,000 bar), pipeline grade hydrogen or helium can purified to produce essentially carbon monoxide -free hydrogen and helium, or carbon monoxide, nitrogen, and methane-free hydrogen and helium.

Golden, Timothy Christopher (Allentown, PA); Farris, Thomas Stephen (Bethlehem, PA)

2008-11-18T23:59:59.000Z

369

Canadian university research reactors  

SciTech Connect

In Canada there are seven university research reactors: one medium-power (2-MW) swimming pool reactor at McMaster University and six low-power (20-kW) SLOWPOKE reactors at Dalhousie University, Ecole Polytechnique, the Royal Military College, the University of Toronto, the University of Saskatchewan, and the University of Alberta. This paper describes primarily the McMaster Nuclear Reactor (MNR), which operates on a wider scale than the SLOWPOKE reactors. The MNR has over a hundred user groups and is a very broad-based tool. The main applications are in the following areas: (1) neutron activation analysis (NAA); (2) isotope production; (3) neutron beam research; (4) nuclear engineering; (5) neutron radiography; and (6) nuclear physics.

Ernst, P.C.; Collins, M.F.

1989-11-01T23:59:59.000Z

370

Reactor & Nuclear Systems Publications | ORNL  

NLE Websites -- All DOE Office Websites (Extended Search)

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

371

NETL: Methane Hydrates - ANS Research Project - Modular Dynamics Tester  

NLE Websites -- All DOE Office Websites (Extended Search)

Well Well Modular Formation Dynamics Tester (MDT) Tool The scientific plan for the Mt. Elbert Prospect includes multiple tests using Schlumberger’s Modular Formation Dynamics Tester (MDT) tool. This device is deployed on wireline and will be used to sample formation fluids, and measure formation pressure and permeability. The tool’s design involves extension of a sampling probe pad against the borehole wall by backup pistons and the insertion of a smaller test probe a small distance into the formation. The probe is then opened to a sampling chamber within the tool, where fluids from the formation can flow, free of contamination by the borehole fluid. The formation pressure is measured using an extremely accurate gauge that can resolve small pressure differences. The pressure and the rate of fluid flow into the sample chamber can be used to calculate reservoir permeability. Multiple probes can also be used to determine both vertical and horizontal permeability data, which can be used to assess near-wellbore permeability anisotropy (i.e., the degree to which vertical and horizontal permeability within the same reservoir differ). All of these data are useful to engineers interested in predicting the productive capability of a reservoir. Various configurations of the MDT tool can be used to accomplish specific testing goals.

372

Modular Integrated Monitoring System (MIMS) field test installations  

SciTech Connect

The MIMS program is funded by the Department of Energy under the Office of Nonproliferation and National Security. The program objective is to develop cost effective, modular, multi-sensor monitoring systems. Both in-plant and ground based sensors are envisioned. It is also desirable to develop sensors/systems that can be fielded/deployed in a rapid fashion. A MIMS architecture was selected to allow modular integration of sensors and systems and is based on LonWorks technology, commercially developed by Echelon Corporation. The first MIMS fieldable hardware was demonstrated at Lawrence Livermore National Laboratory. The field test, known within the DOE as the Item Tracking and Transparency (IT&I) demonstration, involved the collaboration and cooperation of five DOE laboratories (Sandia (SNL), Lawrence Livermore (LLNL), Pacific Northwest (PNL), Los Alamos (LANL), and Oak Ridge (ORNL)). The IT&T demonstration involved the monitoring of special nuclear material as it was transported around the facility utilizing sensors from the participating labs. The scenario was programmed to ignore normal activity in the facility until entry into the room where the material was stored. A second demonstration, which involved three separate scenarios, was conducted at Idaho National Engineering Laboratory (INEL). The participants included representatives from SNL, LLNL, PNL, and INEL. DOE has selected INEL as the long term testbed for MIMS developed sensors, systems, and scenarios. This paper will describe the installation, intended purpose, and results of the field demonstrations at LLNL and INEL under the MIMS program.

Martinez, R.L.; Waymire, D.R. [Sandia National Labs., Albuquerque, NM (United States); Fuess, D.A. [Lawrence Livermore National Lab., CA (United States)] [and others

1995-07-01T23:59:59.000Z

373

646 IEEE TRANSACTIONS ON ROBOTICS AND AUTOMATION, VOL. 13, NO. 5, OCTOBER 1997 Design of Assembly Systems for Modular Products  

E-Print Network (OSTI)

Systems for Modular Products David W. He and Andrew Kusiak, Member, IEEE Abstract--To respond systems. Given a family of modular products, designing low cost assembly systems is an important problem. In this paper, an approach for the design of assembly systems for modular products is proposed. The assembly

Kusiak, Andrew

374

On the Criticality Safety of Transuranic Sodium Fast Reactor Fuel Transport Casks  

SciTech Connect

This work addresses the neutronic performance and criticality safety issues of transport casks for fuel pertaining to low conversion ratio sodium cooled fast reactors, conventionally known as Advanced Burner Reactors. The criticality of a one, three, seven and 19-assembly cask capacity is presented. Both dry helium and flooded water filled casks are considered. No credit for fuel burnup or fission products was assumed. As many as possible of the conservatisms used in licensing light water reactor universal transport casks were incorporated into this SFR cask criticality design and analysis. It was found that at 7-assemblies or more, adding moderator to the SFR cask increases criticality margin. Also, removal of MAs from the fuel increases criticality margin of dry casks and takes a slight amount of margin away for wet casks. Assuming credit for borated fuel tube liners, this design analysis suggests that as many as 19 assemblies can be loaded in a cask if limited purely by criticality safety. If no credit for boron is assumed, the cask could possibly hold seven assemblies if low conversion ratio fast reactor grade fuel and not breeder reactor grade fuel is assumed. The analysis showed that there is a need for new cask designs for fast reactors spent fuel transportation. There is a potential of modifying existing transportation cask design as the starting point for fast reactor spent fuel transportation.

Samuel Bays; Ayodeji Alajo

2010-05-01T23:59:59.000Z

375

UCLA program in reactor studies: The ARIES tokamak reactor study. Progress report, December 1, 1990--November 30, 1991  

SciTech Connect

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

Not Available

1991-12-01T23:59:59.000Z

376

Gas-chromatographische Bestimmung von Wasserstoff bei Verwendung von Helium als Trgergas  

Science Journals Connector (OSTI)

Die bei dem Trgergas Helium zuweilen auftretenden M-frmigen Wasserstoffpeaks lassen sich durch Vergrern oder Verkleinern des Probenvolumens in eine auswertbare Form bringen.

Holm Pauschmann

1964-01-01T23:59:59.000Z

377

Interim Report on the Optimization and Feasibility Studies for the Neutron Detection without Helium-3 Project  

SciTech Connect

This report provides the status and results of the first year's effort in modeling and simulation to investigate alternatives to helium-3 for neutron detection in safeguards applications.

Ely, James H.

2012-03-19T23:59:59.000Z

378

Atmospheric Pressure Helium Plasma Jet with Different Types of Discharge Setup  

Science Journals Connector (OSTI)

New techniques are demonstrated to generate cold plasma inside the glass capillary and hollow optical fiber. The plasma jet is generated using helium gas and experiments are carried...

Hosseinzadeh Kassani, Sahar; Lee, Changyoung; Yoon, Changsik; Choi, Honggu; Oh, Kyunghwan

379

Atmospheric-Pressure Helium Inductively Coupled Plasmas for Elemental Mass Spectrometry  

Science Journals Connector (OSTI)

Analytical and fundamental characteristics of helium inductively coupled plasma mass spectrometry (He ICPMS) were explored for atmospheric-pressure plasmas generated in a 13-mm He...

Zhang, Hao; Nam, Sang-Ho; Cai, Mingxiang; Montaser, Akbar

1996-01-01T23:59:59.000Z

380

Microsoft Word - 911138_0_SSC-6 Helium Circulator Test Plan_rel...  

NLE Websites -- All DOE Office Websites (Extended Search)

SERVICES FOR THE NEXT GENERATION NUCLEAR PLANT (NGNP) WITH HYDROGEN PRODUCTION Test Plan for Helium Circulators (PHTS, SCS, SHTS) Prepared by General Atomics For the...

Note: This page contains sample records for the topic "modular helium reactor" 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

Onboard Hydrogen/Helium Sensors in Support of the Global Technical...  

NLE Websites -- All DOE Office Websites (Extended Search)

Onboard HydrogenHelium Sensors in Support of the Global Technical Regulation: An Assessment of Performance in Fuel Cell Electric Vehicle Crash Tests Matthew B. Post, Robert...

382

Ultra high vacuum pumping system and high sensitivity helium leak detector  

DOE Patents (OSTI)

An improved helium leak detection method and apparatus are disclosed which increase the leak detection sensitivity to 10.sup.-13 atm cc s.sup.-1. The leak detection sensitivity is improved over conventional leak detectors by completely eliminating the use of o-rings, equipping the system with oil-free pumping systems, and by introducing measured flows of nitrogen at the entrances of both the turbo pump and backing pump to keep the system free of helium background. The addition of dry nitrogen flows to the system reduces backstreaming of atmospheric helium through the pumping system as a result of the limited compression ratios of the pumps for helium.

Myneni, Ganapati Rao (Yorktown, VA)

1997-01-01T23:59:59.000Z

383

Ultra high vacuum pumping system and high sensitivity helium leak detector  

DOE Patents (OSTI)

An improved helium leak detection method and apparatus are disclosed which increase the leak detection sensitivity to 10{sup {minus}13} atm cc/s. The leak detection sensitivity is improved over conventional leak detectors by completely eliminating the use of o-rings, equipping the system with oil-free pumping systems, and by introducing measured flows of nitrogen at the entrances of both the turbo pump and backing pump to keep the system free of helium background. The addition of dry nitrogen flows to the system reduces back streaming of atmospheric helium through the pumping system as a result of the limited compression ratios of the pumps for helium. 2 figs.

Myneni, G.R.

1997-12-30T23:59:59.000Z

384

Thermal hydraulic performance testing of printed circuit heat exchangers in a high-temperature helium test facility  

SciTech Connect

In high-temperature gas-cooled reactors, such as a very high temperature reactor (VHTR), an intermediate heat exchanger (IHX) is required to efficiently transfer the core thermal output to a secondary fluid for electricity generation with an indirect power cycle and/or process heat applications. Currently, there is no proven high-temperature (750800 C or higher) compact heat exchanger technology for high-temperature reactor design concepts. In this study, printed circuit heat exchanger (PCHE), a potential IHX concept for high-temperature applications, has been investigated for their heat transfer and pressure drop characteristics under high operating temperatures and pressures. Two PCHEs, each having 10 hot and 10 cold plates with 12 channels (semicircular cross-section) in each plate are fabricated using Alloy 617 plates and tested for their performance in a high-temperature helium test facility (HTHF). The PCHE inlet temperature and pressure were varied from 85 to 390 C/1.02.7 MPa for the cold side and 208790 C/1.02.7 MPa for the hot side, respectively, while the mass flow rate of helium was varied from 15 to 49 kg/h. This range of mass flow rates corresponds to PCHE channel Reynolds numbers of 950 to 4100 for the cold side and 900 to 3900 for the hot side (corresponding to the laminar and laminar-to-turbulent transition flow regimes). The obtained experimental data have been analyzed for the pressure drop and heat transfer characteristics of the heat transfer surface of the PCHEs and compared with the available models and correlations in the literature. In addition, a numerical treatment of hydrodynamically developing and hydrodynamically fully-developed laminar flow through a semicircular duct is presented. Relations developed for determining the hydrodynamic entrance length in a semicircular duct and the friction factor (or pressure drop) in the hydrodynamic entry length region for laminar flow through a semicircular duct are given. Various hydrodynamic entrance region parameters, such as incremental pressure drop number, apparent Fanning friction factor, and hydrodynamic entrance length in a semicircular duct have been numerically estimated.

Sai K. Mylavarapu; Xiaodong Sun; Richard E. Glosup; Richard N. Christensen; Michael W. Patterson

2014-04-01T23:59:59.000Z

385

Nuclear reactor control column  

DOE Patents (OSTI)

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

Bachovchin, Dennis M. (Plum Borough, PA)

1982-01-01T23:59:59.000Z

386

Reactor Safety Research Programs  

SciTech Connect

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

Edler, S. K.

1981-07-01T23:59:59.000Z

387

Advanced Gas Cooled Nuclear Reactor Materials Evaluation and Development Program. Progress report, April 1, 1980-June 30, 1980  

SciTech Connect

Objectives of this program are to evaluate candidate alloys for Very High Temperature Reactor (VHTR) Nuclear Process Heat (NPH) and Direct Cycle Helium Turbine (DCHT) applications, in terms of the effect of simulated reactor primary coolant (helium containing small amounts of various other gases), high temperatures, and long time exposures, on the mechanical properties and structural and surface stability of selected candidate alloys. A second objective is to select and recommend materials for future test facilities and more extensive qualification programs. Work covered in this report includes the activities associated with the status of the simulated reactor helium supply system, testing equipment and gas chemistry analysis instrumentation and equipment. The progress in the screening test program is described; this includes: screening creep results and metallographic analysis for materials thermally exposed or tested at 750, 850 and 950/sup 0/C. The initiation of air creep-rupture testing in the intensive screening test program is discussed. In addition, the status of the data management system is described.

Not Available

1980-11-14T23:59:59.000Z

388

Nuclear reactor reflector  

DOE Patents (OSTI)

A nuclear reactor reflector is disclosed that comprises a stack of reflector blocks with vertical water flow passages to cool the reflector. The interface between blocks is opposite support points for reactor fuel rods. Water flows between the reflector and the reactor barrel from passages in a bottom block. The top block contains a flange to limit this flow and the flange has a slot to receive an alignment pin that is welded to the barrel. The pin is held in the slot by two removable shims. Alignment bars extend the length of the stack in slots machined in each block when the stack is assembled.

Hopkins, Ronald J. (Pensacola, FL); Land, John T. (Pensacola, FL); Misvel, Michael C. (Pensacola, FL)

1994-01-01T23:59:59.000Z

389

Spherical torus fusion reactor  

DOE Patents (OSTI)

The object of this invention is to provide a compact torus fusion reactor with dramatic simplification of plasma confinement design. Another object of this invention is to provide a compact torus fusion reactor with low magnetic field and small aspect ratio stable plasma confinement. In accordance with the principles of this invention there is provided a compact toroidal-type plasma confinement fusion reactor in which only the indispensable components inboard of a tokamak type of plasma confinement region, mainly a current conducting medium which carries electrical current for producing a toroidal magnet confinement field about the toroidal plasma region, are retained.

Martin Peng, Y.K.M.

1985-10-03T23:59:59.000Z

390

Cathode fall measurement in a dielectric barrier discharge in helium  

SciTech Connect

A method based on the zero-length voltage extrapolation is proposed to measure cathode fall in a dielectric barrier discharge. Starting, stable, and discharge-maintaining voltages were measured to obtain the extrapolation zero-length voltage. Under our experimental conditions, the zero-length voltage gave a cathode fall of about 185 V. Based on the known thickness of the cathode fall region, the spatial distribution of the electric field strength in dielectric barrier discharge in atmospheric helium is determined. The strong cathode fall with a maximum field value of approximately 9.25 kV/cm was typical for the glow mode of the discharge.

Hao, Yanpeng; Zheng, Bin; Liu, Yaoge [School of Electric Power, South China University of Technology, Guangzhou 510640 (China)] [School of Electric Power, South China University of Technology, Guangzhou 510640 (China)

2013-11-15T23:59:59.000Z

391

Radiative Lifetimes of Some Electronic States of Helium  

Science Journals Connector (OSTI)

In this paper we describe our measurements of the radiative lifetimes of the 3 3 P 3 3 D 4 1 D and 4 3 D electronic states of helium using a low-energy positive ion accelerator. The lifetimes in nanoseconds are 3 3 P?(1115) 3 3 D?(143) 4 1 D?(344) and 4 3 D?(321) . In addition we discuss the desirability and feasibility of introducing undergraduates to this type of research.

Stanley A. Chin-Bing; Charles E. Head; Albert E. Green Jr.

1970-01-01T23:59:59.000Z

392

A pencil beam algorithm for helium ion beam therapy  

SciTech Connect

Purpose: To develop a flexible pencil beam algorithm for helium ion beam therapy. Dose distributions were calculated using the newly developed pencil beam algorithm and validated using Monte Carlo (MC) methods. Methods: The algorithm was based on the established theory of fluence weighted elemental pencil beam (PB) kernels. Using a new real-time splitting approach, a minimization routine selects the optimal shape for each sub-beam. Dose depositions along the beam path were determined using a look-up table (LUT). Data for LUT generation were derived from MC simulations in water using GATE 6.1. For materials other than water, dose depositions were calculated by the algorithm using water-equivalent depth scaling. Lateral beam spreading caused by multiple scattering has been accounted for by implementing a non-local scattering formula developed by Gottschalk. A new nuclear correction was modelled using a Voigt function and implemented by a LUT approach. Validation simulations have been performed using a phantom filled with homogeneous materials or heterogeneous slabs of up to 3 cm. The beams were incident perpendicular to the phantoms surface with initial particle energies ranging from 50 to 250 MeV/A with a total number of 10{sup 7} ions per beam. For comparison a special evaluation software was developed calculating the gamma indices for dose distributions. Results: In homogeneous phantoms, maximum range deviations between PB and MC of less than 1.1% and differences in the width of the distal energy falloff of the Bragg-Peak from 80% to 20% of less than 0.1 mm were found. Heterogeneous phantoms using layered slabs satisfied a {gamma}-index criterion of 2%/2mm of the local value except for some single voxels. For more complex phantoms using laterally arranged bone-air slabs, the {gamma}-index criterion was exceeded in some areas giving a maximum {gamma}-index of 1.75 and 4.9% of the voxels showed {gamma}-index values larger than one. The calculation precision of the presented algorithm was considered to be sufficient for clinical practice. Although only data for helium beams was presented, the performance of the pencil beam algorithm for proton beams was comparable. Conclusions: The pencil beam algorithm developed for helium ions presents a suitable tool for dose calculations. Its calculation speed was evaluated to be similar to other published pencil beam algorithms. The flexible design allows easy customization of measured depth-dose distributions and use of varying beam profiles, thus making it a promising candidate for integration into future treatment planning systems. Current work in progress deals with RBE effects of helium ions to complete the model.

Fuchs, Hermann; Stroebele, Julia; Schreiner, Thomas; Hirtl, Albert; Georg, Dietmar [Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna, 1090 Vienna (Austria); Department of Radiation Oncology, Medical University of Vienna/AKH Vienna, 1090 Vienna (Austria) and Comprehensive Cancer Center, Medical University of Vienna/AKH Vienna, 1090 Vienna (Austria); Department of Radiation Oncology, Medical University of Vienna/AKH Vienna (Austria) and Comprehensive Cancer Center, Medical University of Vienna/AKH Vienna, 1090 Vienna (Austria); PEG MedAustron, 2700 Wiener Neustadt (Austria); Department of Nuclear Medicine, Medical University of Vienna, 1090 Vienna (Austria); Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna, 1090 Vienna (Austria); Department of Radiation Oncology, Medical University of Vienna/AKH Vienna, 1090 Vienna (Austria) and Comprehensive Cancer Center, Medical University of Vienna/AKH Vienna, 1090 Vienna (Austria)

2012-11-15T23:59:59.000Z

393

Quartz Tuning Fork: Thermometer, Pressure- and Viscometer for Helium Liquids  

E-Print Network (OSTI)

Commercial quartz oscillators of the tuning-fork type with a resonant frequency of ~32 kHz have been investigated in helium liquids. The oscillators are found to have at best Q values in the range 10^5-10^6, when measured in vacuum below 1.5 K. However, the variability is large and for very low temperature operation the sensor has to be preselected. We explore their properties in the regime of linear viscous hydrodynamic response in normal and superfluid 3He and 4He, by comparing measurements to the hydrodynamic model of the sensor.

R. Blaauwgeers; M. Blazkova; M. Clovecko; V. B. Eltsov; R. de Graaf; J. Hosio; M. Krusius; D. Schmoranzer; W. Schoepe; L. Skrbek; P. Skyba; R. E. Solntsev; D. E. Zmeev

2006-08-17T23:59:59.000Z

394

Office of Nuclear Energy | Department of Energy  

Office of Environmental Management (EM)

Office of Nuclear Energy Small Modular Reactors Small Modular Reactors The Small Modular Reactor program advances the licensing and commercialization of this next-generation...

395

The neutronics studies of fusion fission hybrid power reactor  

SciTech Connect

In this paper, a series of neutronics analysis of hybrid power reactor is proposed. The ideas of loading different fuels in a modular-type fission blanket is analyzed, fitting different level of fusion developments, i.e., the current experimental power output, the level can be obtained in the coming future and the high-power fusion reactor like ITER. The energy multiplication of fission blankets and tritium breeding ratio are evaluated as the criterion of design. The analysis is implemented based on the D-type simplified model, aiming to find a feasible 1000MWe hybrid power reactor for 5 years' lifetime. Three patterns are analyzed: 1) for the low fusion power, the reprocessed fuel is chosen. The fuel with high plutonium content is loaded to achieve large energy multiplication. 2) For the middle fusion power, the spent fuel from PWRs can be used to realize about 30 times energy multiplication. 3) For the high fusion power, the natural uranium can be directly used and about 10 times energy multiplication can be achieved.

Zheng Youqi; Wu Hongchun; Zu Tiejun; Yang Chao; Cao Liangzhi [School of Nuclear Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049 (China)

2012-06-19T23:59:59.000Z

396

Improving Ventilation and Saving Energy: Laboratory Study in a Modular  

NLE Websites -- All DOE Office Websites (Extended Search)

Improving Ventilation and Saving Energy: Laboratory Study in a Modular Improving Ventilation and Saving Energy: Laboratory Study in a Modular Classroom Test Bed Title Improving Ventilation and Saving Energy: Laboratory Study in a Modular Classroom Test Bed Publication Type Report Year of Publication 2005 Authors Apte, Michael G., Ian S. Buchanan, David Faulkner, William J. Fisk, Chi-Ming Lai, Michael Spears, and Douglas P. Sullivan Publisher Lawrence Berkeley National Laboratory Abstract The primary goals of this research effort were to develop, evaluate, and demonstrate a practical HVAC system for classrooms that consistently provides classrooms with the quantity of ventilation in current minimum standards, while saving energy, and reducing HVAC-related noise levels. This research was motivated by several factors, including the public benefits of energy efficiency, evidence that many classrooms are under-ventilated, and public concerns about indoor environmental quality in classrooms. This project involved the installation and verification of the performance of an Improved Heat Pump Air Conditioning (IHPAC) system, and its comparison, a standard HVAC system having an efficiency of 10 SEER. The project included the verification of the physical characteristics suitable for direct replacement of existing 10 SEER systems, quantitative demonstration of improved energy efficiency, reduced acoustic noise levels, quantitative demonstration of improved ventilation control, and verification that the system would meet temperature control demands necessary for the thermal comfort of the occupants. Results showed that the IHPAC met these goals. The IHPAC was found to be a direct bolt-on replacement for the 10 SEER system. Calculated energy efficiency improvements based on many days of classroom cooling or heating showed that the IHPAC system is about 44% more efficient during cooling and 38% more efficient during heating than the 10 SEER system. Noise reduction was dramatic, with measured A-weighed sound level for fan only operation conditions of 34.3 dB(A), a reduction of 19 dB(A) compared to the 10 SEER system. Similarly, the IHPAC stage-1 and stage-2 compressor plus fan sound levels were 40.8 dB(A) and 42.7 dB(A), reductions of 14 and 13 dB(A), respectively. Thus, the IHPAC is 20 to 35 times quieter than the 10 SEER systems depending upon the operation mode. The IHPAC system met the ventilation requirements and was able to provide consistent outside air supply throughout the study. Indoor CO2 levels with simulated occupancy were maintained below 1000 ppm. Finally temperature settings were met and controlled accurately. The goals of the laboratory testing phase were met and this system is ready for further study in a field test of occupied classrooms

397

The effect of helium nano-bubbles on the structures stability and electronic properties of palladium tritides: a density functional theory study  

Science Journals Connector (OSTI)

...effect of helium nano-bubbles on the structures stability and electronic properties...found to contain helium gas bubbles. The stability of metal tritides decreases...The effects of helium bubbles on metal tritides are clearly...

2014-01-01T23:59:59.000Z

398

Insights from the WGRISK workshop on the PSA of advanced and new reactors  

SciTech Connect

Probabilistic Safety Assessment /Probabilistic Risk Assessment for new and advanced reactors is recognized as an essential complement of the deterministic approaches to achieve improved safety and performances of new nuclear power plants, comparing to the operating plants. However, the development of PSA to these reactors is encountered to concurrent challenges, mainly due to the limited available design information, as well as due to potentially new initiating events, accident sequences and phenomena. The use of PSA in the decision making process is also challenging since the resulting PSA may not sufficiently reflect the future as-built, as-operated plant information. In order to address these aspects, the OECD/NEA/WGRISK initiated two coordinated tasks on 'PSA for Advanced Reactors' and 'PSA in the frame of Design and Commissioning of New NPPs'. In this context, a joint workshop was organized by OECD, during which related subjects were presented and discussed, including PSA for generation IV reactors, PSA for evolutionary reactors, PSA for small modular reactors, severe accidents and Level 2 PSA, Level 3 PSA and consequences analysis, digital I and C modeling, passive systems reliability, safety-security interface, as well as the results of the surveys performed in the frame of theses WGRISK tasks. (authors)

Georgescu, G. [Inst. for Radioprotection and Nuclear Safety IRSN, BP17, 92262 Fontenay aux Roses (France); Ahn, K. I. [Korea Atomic Energy Research Inst. KAERI, 150-1 Deokjin-Dong, 1045 Daedeokdaero, Yuseong, Daejeon (Korea, Republic of); Amri, A. [OCED/NEA, Le Seine St.Germain, Bd des Iles, 92130 Issy-les-Moulineaux (France)

2012-07-01T23:59:59.000Z

399

Enhanced modularity-based community detection by random walk network preprocessing  

Science Journals Connector (OSTI)

The representation of real systems with network models is becoming increasingly common and critical to both capture and simplify systems complexity, notably, via the partitioning of networks into communities. In this respect, the definition of modularity, a common and broadly used quality measure for networks partitioning, has induced a surge of efficient modularity-based community detection algorithms. However, recently, the optimization of modularity has been found to show a resolution limit, which reduces its effectiveness and range of applications. Therefore, one recent trend in this area of research has been related to the definition of novel quality functions, alternative to modularity. In this paper, however, instead of laying aside the important body of knowledge developed so far for modularity-based algorithms, we propose to use a strategy to preprocess networks before feeding them into modularity-based algorithms. This approach is based on the observation that dynamic processes triggered on vertices in the same community possess similar behavior patterns but dissimilar on vertices in different communities. Validations on real-world and synthetic networks demonstrate that network preprocessing can enhance the modularity-based community detection algorithms to find more natural clusters and effectively alleviates the problem of resolution limit.

Darong Lai; Hongtao Lu; Christine Nardini

2010-06-23T23:59:59.000Z

400

Further experiments with liquid helium. C. On the change of electric resistance of pure metals at very low temperatures etc. IV. The resistance of pure mercury at helium temperatures  

Science Journals Connector (OSTI)

Since the appearance of the last Communication dealing with liquid helium temperatures (December 1910) liquid helium has been succesfully transferred from the apparatus in which it was liquefied to another ves...

H. Kamerlingh Onnes

1991-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modular helium reactor" 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

Reactor Thermal-Hydraulics  

NLE Websites -- All DOE Office Websites (Extended Search)

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

402

Reactor hot spot analysis  

SciTech Connect

The principle methods for performing reactor hot spot analysis are reviewed and examined for potential use in the Applied Physics Division. The semistatistical horizontal method is recommended for future work and is now available as an option in the SE2-ANL core thermal hydraulic code. The semistatistical horizontal method is applied to a small LMR to illustrate the calculation of cladding midwall and fuel centerline hot spot temperatures. The example includes a listing of uncertainties, estimates for their magnitudes, computation of hot spot subfactor values and calculation of two sigma temperatures. A review of the uncertainties that affect liquid metal fast reactors is also presented. It was found that hot spot subfactor magnitudes are strongly dependent on the reactor design and therefore reactor specific details must be carefully studied. 13 refs., 1 fig., 5 tabs.

Vilim, R.B.

1985-08-01T23:59:59.000Z

403

Molten metal reactors  

DOE Patents (OSTI)

A molten metal reactor for converting a carbon material and steam into a gas comprising hydrogen, carbon monoxide, and carbon dioxide is disclosed. The reactor includes an interior crucible having a portion contained within an exterior crucible. The interior crucible includes an inlet and an outlet; the outlet leads to the exterior crucible and may comprise a diffuser. The exterior crucible may contain a molten alkaline metal compound. Contained between the exterior crucible and the interior crucible is at least one baffle.

Bingham, Dennis N; Klingler, Kerry M; Turner, Terry D; Wilding, Bruce M

2013-11-05T23:59:59.000Z

404

F Reactor Inspection  

ScienceCinema (OSTI)

Workers from Mission Support Alliance, LLC., removed the welds around the steel door of the F Reactor before stepping inside the reactor to complete its periodic inspection. This is the first time the Department of Energy (DOE) has had the reactor open since 2008. The F Reactor is one of nine reactors along the Columbia River at the Department's Hanford Site in southeastern Washington State, where environmental cleanup has been ongoing since 1989. As part of the Tri-Party Agreement, the Department completes surveillance and maintenance activities of cocooned reactors periodically to evaluate the structural integrity of the safe storage enclosure and to ensure confinement of any remaining hazardous materials. "This entry marks a transition of sorts because the Hanford Long-Term Stewardship Program, for the first time, was responsible for conducting the entry and surveillance and maintenance activities," said Keith Grindstaff, Energy Department Long-Term Stewardship Program Manager. "As the River Corridor cleanup work is completed and transitioned to long-term stewardship, our program will manage any on-going requirements."

Grindstaff, Keith; Hathaway, Boyd; Wilson, Mike

2014-11-24T23:59:59.000Z

405

F Reactor Inspection  

SciTech Connect

Workers from Mission Support Alliance, LLC., removed the welds around the steel door of the F Reactor before stepping inside the reactor to complete its periodic inspection. This is the first time the Department of Energy (DOE) has had the reactor open since 2008. The F Reactor is one of nine reactors along the Columbia River at the Department's Hanford Site in southeastern Washington State, where environmental cleanup has been ongoing since 1989. As part of the Tri-Party Agreement, the Department completes surveillance and maintenance activities of cocooned reactors periodically to evaluate the structural integrity of the safe storage enclosure and to ensure confinement of any remaining hazardous materials. "This entry marks a transition of sorts because the Hanford Long-Term Stewardship Program, for the first time, was responsible for conducting the entry and surveillance and maintenance activities," said Keith Grindstaff, Energy Department Long-Term Stewardship Program Manager. "As the River Corridor cleanup work is completed and transitioned to long-term stewardship, our program will manage any on-going requirements."

Grindstaff, Keith; Hathaway, Boyd; Wilson, Mike

2014-10-29T23:59:59.000Z

406

The helium-rich cataclysmic variable SBSS 1108+574  

E-Print Network (OSTI)

We present time-resolved spectroscopy and photometry of the dwarf nova SBSS 1108+574, obtained during the 2012 outburst. Its quiescent spectrum is unusually rich in helium, showing broad, double-peaked emission lines from the accretion disc. We measure a line flux ratio HeI 5875/Halpha = 0.81 +/- 0.04, a much higher ratio than typically observed in cataclysmic variables (CVs). The outburst spectrum shows hydrogen and helium in absorption, with weak emission of Halpha and HeI 6678, as well as strong HeII emission. From our photometry, we find the superhump period to be 56.34 +/- 0.18 minutes, in agreement with the previously published result. The spectroscopic period, derived from the radial velocities of the emission lines, is found to be 55.3 +/- 0.8 minutes, consistent with a previously identified photometric orbital period, and significantly below the normal CV period minimum. This indicates that the donor in SBSS 1108+574 is highly evolved. The superhump excess derived from our photometry implies a mass r...

Carter, P J; de Miguel, E; Goff, W; Koff, R A; Krajci, T; Marsh, T R; Gnsicke, B T; Breedt, E; Groot, P J; Nelemans, G; Roelofs, G H A; Rau, A; Koester, D; Kupfer, T

2013-01-01T23:59:59.000Z

407

Neutron Irradiation Tests of Pressure Transducers in Liquid Helium  

E-Print Network (OSTI)

The superconducting magnets of the future Large Hadron Collider (LHC) at CERN will operate in pressurised superfluid helium (1 bar, 1.9 K). About 500 pressure transducers will be placed in the liquid helium bath for monitoring the filling and the pressure transients after resistive transitions. Their precision must remain better than 100 mbar at pressures below 2 bar and better than 5% for higher pressures (up to 20 bar), with temperatures ranging from 1.8 K to 300 K. All the tested transducers are based on the same principle: the fluid or gas is separated from a sealed reference vacuum by an elastic membrane; its deformation indicates the pressure. The transducers will be exposed to high neutron fluence (2 kGy, 1014 n/cm2 per year) during the 20 years of machine operation. This irradiation may induce changes both on the membranes characteristics (leakage, modification of elasticity) and on gauges which measure their deformations. To investigate these effects and select the transducer to be used in the LHC, a...

Amand, J F; Casas-Cubillos, J; Thermeau, J P

1999-01-01T23:59:59.000Z

408

Ignition and extinction phenomena in helium micro hollow cathode discharges  

SciTech Connect

Micro hollow cathode discharges (MHCD) were produced using 250??m thick dielectric layer of alumina sandwiched between two nickel electrodes of 8??m thickness. A through cavity at the center of the chip was formed by laser drilling technique. MHCD with a diameter of few hundreds of micrometers allowed us to generate direct current discharges in helium at up to atmospheric pressure. A slowly varying ramped voltage generator was used to study the ignition and the extinction periods of the microdischarges. The analysis was performed by using electrical characterisation of the V-I behaviour and the measurement of He*({sup 3}S{sub 1}) metastable atoms density by tunable diode laser spectroscopy. At the ignition of the microdischarges, 2??s long current peak as high as 24?mA was observed, sometimes followed by low amplitude damped oscillations. At helium pressure above 400?Torr, an oscillatory behaviour of the discharge current was observed just before the extinction of the microdischarges. The same type of instability in the extinction period at high pressure also appeared on the density of He*({sup 3}S{sub 1}) metastable atoms, but delayed by a few ?s relative to the current oscillations. Metastable atoms thus cannot be at the origin of the generation of the observed instabilities.

Kulsreshath, M. K.; Schwaederle, L.; Dufour, T.; Lefaucheux, P.; Dussart, R. [GREMI, CNRS/Universit d'Orlans (UMR7344), Orlans (France); Sadeghi, N. [LIPhy, CNRS and Universite Joseph Fourier (UMR5588), Grenoble (France); Overzet, L. J. [GREMI, CNRS/Universit d'Orlans (UMR7344), Orlans (France); PSAL, UTDallas, Richardson, Texas 75080-3021 (United States)

2013-12-28T23:59:59.000Z

409

The Source of the Helium Visible Lines in Eta Carinae  

E-Print Network (OSTI)

We assume that the helium-I lines emitted by the massive binary system Eta Carinae are formed in the acceleration zone of the less-massive secondary star. We calculate the Doppler shift of the lines as a function of orbital phase and of several parameters of the binary system. We find that a good fit is obtained if the helium lines are formed in the region where the secondary wind speed is 430 km/sec. The acceptable binary eccentricity is in the range 0.9-0.95, and the inclination angle (the angle between a line perpendicular to the orbital plane and the line of sight) is in the range 40-55 degrees. Lower values of e require higher values of i, and vice versa. The binary system is oriented such that the secondary star is in our direction (closer to us) during periastron passage. The orbital motion can account in part to the Doppler shift of the peak in X-ray emission.

Amit Kashi; Noam Soker

2007-02-25T23:59:59.000Z

410

The Source of the Helium Visible Lines in Eta Carinae  

E-Print Network (OSTI)

We assume that the helium-I lines emitted by the massive binary system Eta Carinae are formed in the acceleration zone of the less-massive secondary star. We calculate the Doppler shift of the lines as a function of orbital phase and of several parameters of the binary system. We find that a good fit is obtained if the helium lines are formed in the region where the secondary wind speed is 430 km/sec. The acceptable binary eccentricity is in the range 0.9-0.95, and the inclination angle (the angle between a line perpendicular to the orbital plane and the line of sight) is in the range 40-55 degrees. Lower values of e require higher values of i, and vice versa. The binary system is oriented such that the secondary star is in our direction (closer to us) during periastron passage. The orbital motion can account in part to the Doppler shift of the peak in X-ray emission.

Kashi, A; Kashi, Amit; Soker, Noam

2007-01-01T23:59:59.000Z

411

Technical Report No.7, Investigation of radon and helium as possible fluid-phase precursors to earthquakes. Technical Report No. 2, Additional task: Radon, helium and geochemical monitoring on the Palmdale uplift.  

E-Print Network (OSTI)

Imperial Valley) HELIUM AND All with RADON IN WELL SAMPLES of the wells in the Southern Network are geothermal

Craig, H; Lupton, J E; Chung, Y; Horowitz, R M

1977-01-01T23:59:59.000Z

412

Retrieval and Repackaging of RH-TRU Waste - General Presentation Modular Hot Cell Technology  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Paul Murray Paul Murray Oak Ridge, TN July 29, 2009 Retrieval and Repackaging of RH-TRU Waste- GENERAL PRESENTATION MODULAR HOT CELL TECHNOLOGY AREVA FEDERAL SERVICES - OAK RIDGE, TN - GENERAL PRESENTATION OF MODULAR HOT CELL TECHNOLOGY - July 29, 2009 ADAPTING AREVA'S TECHNOLOGY AREVA Worldwide Nuclear Lifecycle Transmission & Distribution Renewable Energy AREVA US Nuclear Fuel Services Nuclear Engineering Services AREVA Federal Services, LLC. (AFS) Federal Services Major Projects * MOX-MFFF * Yucca Mountain Project * DUF6 * Plateau Remediation Contract * Washington River Closure Project * SRS Liquid Waste AREVA FEDERAL SERVICES - OAK RIDGE, TN - GENERAL PRESENTATION OF MODULAR HOT CELL TECHNOLOGY - July 29, 2009 ADAPTING AREVA'S TECHNOLOGY AFS Technology Provider

413

Faraday and Cotton-Mouton Effects of Helium at = 1064 nm A. Cad`ene1  

E-Print Network (OSTI)

Faraday and Cotton-Mouton Effects of Helium at = 1064 nm A. Cad`ene1 , D. Sordes1 , P. Berceau1 of the Faraday and the Cotton-Mouton effects of helium gas at = 1064 nm. Our apparatus is based on an up and Cotton-Mouton effect. Our measurements give for the first time the experimental value of the Faraday

Paris-Sud XI, Université de

414

Difference in formation of hydrogen and helium clusters in tungsten K. O. E. Henriksson,a  

E-Print Network (OSTI)

Difference in formation of hydrogen and helium clusters in tungsten K. O. E. Henriksson,a K online 12 October 2005 The experimentally observed large difference in the depths of hydrogen and helium and He embrittlement of materials. Yet many of the basic properties of such systems are not well

Krasheninnikov, Arkady V.

415

The Solar Wind Helium Abundance: Variation with Wind Speed and the Solar Cycle  

E-Print Network (OSTI)

The Solar Wind Helium Abundance: Variation with Wind Speed and the Solar Cycle Matthias R. Aellig Alamos National Lab., Los Alamos, NM 87545 Abstract We investigate the helium abundance in the solar wind of 1994 and early 2000 are analyzed. In agreement with similar work for previous solar cycles, we find

Richardson, John

416

Cryogenic (<20 K) helium cooling mitigates radiation damage to protein crystals  

Science Journals Connector (OSTI)

Comparison of diffraction data collected from matched protein crystals bathed in helium at a set temperature of 8 K and nitrogen at 100 K indicate that the use of cryogenic helium can increase the diffractive lifetime of crystals and measurably mitigate radiation damage.

Chinte, U.

2007-03-16T23:59:59.000Z

417

Hydrogen and helium entrapment in flowing liquid metal plasma-facing surfaces  

E-Print Network (OSTI)

Hydrogen and helium entrapment in flowing liquid metal plasma-facing surfaces Ahmed Hassanein the PFC surface (helium and hydrogen isotopes) while accommodating high heat loads. To study this problem. Hydrogen isotope (DT) particles are likely be trapped in the liquid metal surface (e.g., lithium) due

Harilal, S. S.

418

Activation of the liquid helium contamination during its passage in the Collider ring  

SciTech Connect

Radioactivation of possible contamination of the liquid helium trapped in the arcs of the Collider ring of the Superconducting Super Collider and transported by the liquid helium is estimated. This estimation is used to calculate the dose rate on the filter of the refrigerator plant located at the top of the shaft.

Lopez, G.

1994-01-01T23:59:59.000Z

419

Comparison Between Air and Helium for Use as Working Fluids in the Energy-Conversion Cycle of the MPBR  

E-Print Network (OSTI)

A comparison between air and helium for use as working fluids in the energy-conversion cycle of the MPBR is presented. To date, helium has been selected in the MPBR indirect-cycle working reference design. Air open- and ...

Galen, T. A.

420

Helium Refrigerator Liquid Nitrogen Pre-Cooler Component Parameter Sensitivity Analysis  

SciTech Connect

For helium refrigerators using liquid nitrogen (LN) pre-cooling it is not uncommon for the ambient helium refrigeration return stream(s) exiting the cold box to be significantly colder and for the cycle to use more nitrogen than estimated by the process studies. Often there is an emphasis on the length of 300 to 80-K helium-nitrogen heat exchangers to ensure the exiting nitrogen is as close to ambient as possible. However, it is really the size and flow distribution of the 300 to 80-K helium-helium heat exchangers which are the dominate influence of the nitrogen consumption. As such, an analysis was done to identify and quantify the sensitivity the key parameters in the refrigerator LN pre-cooler section affecting the LN consumption.

Peter Knudsen, Venkatarao Ganni

2010-04-01T23:59:59.000Z

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


421

The Initiation and Propagation of Helium Detonations in White Dwarf Envelopes  

E-Print Network (OSTI)

Detonations in helium-rich envelopes surrounding white dwarfs have garnered attention as triggers of faint thermonuclear ".Ia" supernovae and double detonation Type Ia supernovae. However, recent studies have found that the minimum size of a hotspot that can lead to a helium detonation is comparable to, or even larger than, the white dwarf's pressure scale height, casting doubt on the successful ignition of helium detonations in these systems. In this paper, we examine the previously neglected effects of C/O pollution and a full nuclear reaction network, and we consider hotspots with spatially constant pressure in addition to constant density hotspots. We find that the inclusion of these effects significantly decreases the minimum hotspot size for helium-rich detonation ignition, making detonations far more plausible during turbulent shell convection or during double white dwarf mergers. The increase in burning rate also decreases the minimum shell mass in which a helium detonation can successfully propagate ...

Shen, Ken J

2014-01-01T23:59:59.000Z

422

Regional And Local Trends In Helium Isotopes, Basin And Range Province,  

Open Energy Info (EERE)

And Local Trends In Helium Isotopes, Basin And Range Province, And Local Trends In Helium Isotopes, Basin And Range Province, Western North America- Evidence For Deep Permeable Pathways Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Paper: Regional And Local Trends In Helium Isotopes, Basin And Range Province, Western North America- Evidence For Deep Permeable Pathways Details Activities (1) Areas (1) Regions (0) Abstract: Fluids from the western margin of the Basin and Range have helium isotope ratios as high as ~6-7 Ra, indicating a strong mantle melt influence and consistent with recent and current volcanic activity. Moving away from these areas, helium isotope ratios decrease rapidly to 'background' values of around 0.6 Ra, and then gradually decrease toward the east to low values of ~0.1 Ra at the eastern margin of the Basin and

423

The helium-core mass at the helium flash in low-mass red giant stars observations and theory  

E-Print Network (OSTI)

The method developed by Raffelt (1990a,b,c) to estimate a possible increase in the standard values of the helium-core mass at the tip of the red giant branch, \\Mc, from properties of the color-magnitude diagrams of Galactic globular clusters is employed. In the present study, we revise and update Raffelt's database, including also constraints from RR Lyrae pulsation, and find that a small increase, by \\Delta\\Mc \\approx 0.01\\pm 0.015 \\Msun, cannot be ruled out with the present data and evolutionary models. Our new upper limits on \\Delta\\Mc are less restrictive than those previously obtained by Raffelt, as are the corresponding constraints on novel astroparticle phenomena which may affect the evolution of low-mass red giants. Within the estimated uncertainties, however, the standard values of \\Mc may also be acceptable. Raffelt's method does not rule out a low envelope helium abundance in globular cluster giants, though again the standard values are compatible with the available constraints. The influence of a ...

Catelan, M

1995-01-01T23:59:59.000Z

424

REACTOR GROUT THERMAL PROPERTIES  

SciTech Connect

Savannah River Site has five dormant nuclear production reactors. Long term disposition will require filling some reactor buildings with grout up to ground level. Portland cement based grout will be used to fill the buildings with the exception of some reactor tanks. Some reactor tanks contain significant quantities of aluminum which could react with Portland cement based grout to form hydrogen. Hydrogen production is a safety concern and gas generation could also compromise the structural integrity of the grout pour. Therefore, it was necessary to develop a non-Portland cement grout to fill reactors that contain significant quantities of aluminum. Grouts generate heat when they set, so the potential exists for large temperature increases in a large pour, which could compromise the integrity of the pour. The primary purpose of the testing reported here was to measure heat of hydration, specific heat, thermal conductivity and density of various reactor grouts under consideration so that these properties could be used to model transient heat transfer for different pouring strategies. A secondary purpose was to make qualitative judgments of grout pourability and hardened strength. Some reactor grout formulations were unacceptable because they generated too much heat, or started setting too fast, or required too long to harden or were too weak. The formulation called 102H had the best combination of characteristics. It is a Calcium Alumino-Sulfate grout that contains Ciment Fondu (calcium aluminate cement), Plaster of Paris (calcium sulfate hemihydrate), sand, Class F fly ash, boric acid and small quantities of additives. This composition afforded about ten hours of working time. Heat release began at 12 hours and was complete by 24 hours. The adiabatic temperature rise was 54 C which was within specification. The final product was hard and displayed no visible segregation. The density and maximum particle size were within specification.

Steimke, J.; Qureshi, Z.; Restivo, M.; Guerrero, H.

2011-01-28T23:59:59.000Z

425

Reactor Safety Planning for Prometheus Project, for Naval Reactors Information  

SciTech Connect

The purpose of this letter is to submit to Naval Reactors the initial plan for the Prometheus project Reactor Safety work. The Prometheus project is currently developing plans for cold physics experiments and reactor prototype tests. These tests and facilities may require safety analysis and siting support. In addition to the ground facilities, the flight reactor units will require unique analyses to evaluate the risk to the public from normal operations and credible accident conditions. This letter outlines major safety documents that will be submitted with estimated deliverable dates. Included in this planning is the reactor servicing documentation and shipping analysis that will be submitted to Naval Reactors.

P. Delmolino

2005-05-06T23:59:59.000Z

426

Evaluation of Hastelloy X for gas-cooled-reactor applications  

SciTech Connect

Hastelloy X is a potential structural material for use in gas-cooled reactor systems. In this application data are necessary on the mechanical properties of base metals and weldments under realistic service conditions. The test environment studied was helium that contained small amounts of H/sub 2/, CH/sub 4/, and CO. It is shown that this environment is carburizing with the kinetics of this process, becoming rapid above 800/sup 0/C. Suitable weldments of Hastelloy X were prepared by several processes; those weldments generally had properties similar to the base metal except for lower fracture strains under some conditions. Some samples were aged up to 20,000 h in the test gas and tested, and some creep tests on as-received material exceeded 40,000 h. The predominant effect of aging was the significant reduction of the fracture strains at ambient temperature; the strains were lower when the samples were aged in HTGR helium than when aged in inert gas. Under some conditions aging also increased the yield and ultimate tensile strength. Limited impact testing showed that the impact energy at 25/sup 0/C was reduced drastically by aging at 871 and 704/sup 0/C.

McCoy, H.E.; King, J.F.

1982-11-01T23:59:59.000Z

427

B Reactor | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

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

428

New Approach for Feature Selection of Thermomechanically Processed HSLA Steel using Pruned-Modular Neural Networks  

Science Journals Connector (OSTI)

A new approach has been used in modeling of strength and ductility of high strength low alloy (HSLA) steel, where a comparative study among fully-connected neural network, modular network and pruned-module arc...

Prasun Das; Avishek Ghosh

2012-10-01T23:59:59.000Z

429

Design principles of mammalian signaling networks : emergent properties at modular and global scales  

E-Print Network (OSTI)

This thesis utilizes modeling approaches rooted in statistical physics and physical chemistry to investigate several aspects of cellular signal transduction at both the modular and global levels. Design principles of ...

Locasale, Jason W

2008-01-01T23:59:59.000Z

430

Abstract--We present progress on a comprehensive, modular, interactive modeling environment centered on overall  

E-Print Network (OSTI)

in a cell membrane ion transport protein. In this paper, we present progress on a comprehensive, modular, epithelial transport, or even whole organ physiology, there is presently, no comprehensive, organism

Boyer, Edmond

431

Order and diversity within a modular system for housing : a computational approach  

E-Print Network (OSTI)

This thesis introduces elements of a methodology to achieve order and diversity in the systematic design of street facades within a modular system for housing. In its context both order and diversity refer to the spatial ...

Duarte, Jos Pinto

1993-01-01T23:59:59.000Z

432

Modular invariants and subfactors e-mail: yasuyuki@ms.u-tokyo.ac.jp  

E-Print Network (OSTI)

###### 1994 ###### chiral generator ## Longo-Rehren [13] # 1994 ###### Xu [26, 27] # 1995 ## ####### braided endomorphism (### B"ockenhauer-Evans [1, 2, 3] #### ff-induction ####### net of subfactors ###### subfactor #### 2 ff-induction # modular invariant Ocneanu # double

Kawahigashi, Yasuyuki

433

Prototype Fault Current Limiter Using Transformer and a Modular Device of YBCO Coated Conductor  

Science Journals Connector (OSTI)

A superconducting fault current limiter (SCFL) consisted of a transformer with ... secondary winding short-circuited by a modular superconducting limiter device with 16 elements connected in series ... a 0.125? ...

C. A. Baldan; J. S. Lamas; A. A. Bernardes

2013-04-01T23:59:59.000Z

434

Design and analysis of a concrete modular housing system constructed with 3D panels  

E-Print Network (OSTI)

An innovative modular house system design utilizing an alternative concrete residential building system called 3D panels is presented along with an overview of 3D panels as well as relevant methods and markets. The proposed ...

Sarcia, Sam Rhea, 1982-

2004-01-01T23:59:59.000Z

435

Power management as a system-level inhibitor of modularity in the mobile computer industry  

E-Print Network (OSTI)

Since the mid-90s, the computer industry has been very modular with respect to both product architecture and industry structure. The growing market size of mobile computers means that the challenges facing this segment are ...

Weinstein, Samuel K. (Samuel Keith), 1974-

2004-01-01T23:59:59.000Z

436

Free and bound generics: two techniques for abstract data types in modular C  

Science Journals Connector (OSTI)

A description of two fundamentally distinct techniques for the implementation of abstract data types within Modular C, a preprocessor extension of C. Issues of reusability, environmental design, and efficiency are discussed as criteria for the selection ...

Stowe Boyd

1984-03-01T23:59:59.000Z

437

Passive solar strategies as a logic for improved architectural design: Two prototypes for modular housing  

SciTech Connect

This paper presents a project in which two passive solar housing prototypes were developed for mass production as modular housing. The prototypes have been built and are currently being marketed and thermally monitored. The project received support from the U.S. DOE under its Passive Solar Manufactured Buildings Program. The goal of this project was to develop a prototype which incorporated passive solar technologies into modular housing. Because modular housing is an industrialized product, this incorporation involved relating to a construction process as well as deriving the design of a new product. This paper addresses the issues of modular housing production that impact energy efficiency, passive solar design, and architectural quality. The product's design evolution is described, with emphasis upon how solutions for the prototype(s) were derived in response to factory construction processes, cost, existing and potential markets and the extended goal to improve both energy efficiency and architectural design while introducing passive solar strategies.

Reeder, B.C.

1983-12-01T23:59:59.000Z

438

Introducing MARF: a Modular Audio Recognition Framework and its Applications for Scientific and Software Engineering Research  

Science Journals Connector (OSTI)

In this paper we introduce a Modular Audio Recognition Framework (MARF), as an open ... recognition algorithms and beyond in areas such as audio and text processing (NLP) and may ... learning and extension as it ...

Serguei A. Mokhov

2008-01-01T23:59:59.000Z

439

An MCMC determination of the primordial helium abundance  

SciTech Connect

Spectroscopic observations of the chemical abundances in metal-poor H II regions provide an independent method for estimating the primordial helium abundance. H II regions are described by several physical parameters such as electron density, electron temperature, and reddening, in addition to y, the ratio of helium to hydrogen. It had been customary to estimate or determine self-consistently these parameters to calculate y. Frequentist analyses of the parameter space have been shown to be successful in these parameter determinations, and Markov Chain Monte Carlo (MCMC) techniques have proven to be very efficient in sampling this parameter space. Nevertheless, accurate determination of the primordial helium abundance from observations of H II regions is constrained by both systematic and statistical uncertainties. In an attempt to better reduce the latter, and continue to better characterize the former, we apply MCMC methods to the large dataset recently compiled by Izotov, Thuan, and Stasi?ska (2007). To improve the reliability of the determination, a high quality dataset is needed. In pursuit of this, a variety of cuts are explored. The efficacy of the He I ?4026 emission line as a constraint on the solutions is first examined, revealing the introduction of systematic bias through its absence. As a clear measure of the quality of the physical solution, a ?{sup 2} analysis proves instrumental in the selection of data compatible with the theoretical model. Nearly two-thirds of the observations fall outside a standard 95% confidence level cut, which highlights the care necessary in selecting systems and warrants further investigation into potential deficiencies of the model or data. In addition, the method also allows us to exclude systems for which parameter estimations are statistical outliers. As a result, the final selected dataset gains in reliability and exhibits improved consistency. Regression to zero metallicity yields Y{sub p} = 0.2534 0.0083, in broad agreement with the WMAP result. The inclusion of more observations shows promise for further reducing the uncertainty, but more high quality spectra are required.

Aver, Erik; Olive, Keith A.; Skillman, Evan D., E-mail: aver@physics.umn.edu, E-mail: olive@umn.edu, E-mail: skillman@astro.umn.edu [School of Physics and Astronomy, University of Minnesota, 116 Church St. SE, Minneapolis, MN 55455 (United States)

2012-04-01T23:59:59.000Z

440

Zeeman deceleration of electron-impact-excited metastable helium atoms  

E-Print Network (OSTI)

We present experimental results that demonstrate - for the first time - the Zeeman deceleration of helium atoms in the metastable 2^3S_1state. A more than 40% decrease of the kinetic energy of the beam is achieved for deceleration from 490 m/s to a final velocity of 370 m/s. Metastable atom generation is achieved with an electron-impact-excitation source whose performance is enhanced through an additional discharge-type process which we characterize in detail. Comparison of deceleration data at different electron beam pulse durations confirms that a matching between the initial particle distribution and the phase-space acceptance of the decelerator is crucial for the production of a decelerated packet with a well-defined velocity distribution. The experimental findings are in good agreement with three-dimensional numerical particle trajectory simulations.

Dulitz, Katrin; Softley, Timothy P

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modular helium reactor" 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

Options for Cryogenic Load Cooling with Forced Flow Helium Circulation  

SciTech Connect

Cryogenic pumps designed to circulate super-critical helium are commonly deemed necessary in many super-conducting magnet and other cooling applications. Acknowledging that these pumps are often located at the coldest temperature levels, their use introduces risks associated with the reliability of additional rotating machinery and an additional load on the refrigeration system. However, as it has been successfully demonstrated, this objective can be accomplished without using these pumps by the refrigeration system, resulting in lower system input power and improved reliability to the overall cryogenic system operations. In this paper we examine some trade-offs between using these pumps vs. using the refrigeration system directly with examples of processes that have used these concepts successfully and eliminated using such pumps

Peter Knudsen, Venkatarao Ganni, Roberto Than

2012-06-01T23:59:59.000Z

442

Friction-Induced Fluid Heating in Nanoscale Helium Flows  

SciTech Connect

We investigate the mechanism of friction-induced fluid heating in nanoconfinements. Molecular dynamics simulations are used to study the temperature variations of liquid helium in nanoscale Poiseuille flows. It is found that the fluid heating is dominated by different sources of friction as the external driving force is changed. For small external force, the fluid heating is mainly caused by the internal viscous friction in the fluid. When the external force is large and causes fluid slip at the surfaces of channel walls, the friction at the fluid-solid interface dominates over the internal friction in the fluid and is the major contribution to fluid heating. An asymmetric temperature gradient in the fluid is developed in the case of nonidentical walls and the general temperature gradient may change sign as the dominant heating factor changes from internal to interfacial friction with increasing external force.

Li Zhigang [Department of Mechanical Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon (Hong Kong)

2010-05-21T23:59:59.000Z

443

Design of oilfree all turbo-type helium refrigerator  

Science Journals Connector (OSTI)

We have designed a high efficient, compact 300 W oilfree all turbo-type heliumrefrigerator capable of long maintenance free continuous operation. The main compressor at ambient temperature which is driven by a helium gas turbine attached to the same shaft, is supported by magnetic bearings, and, has an inlet and outlet pressure of 0.35 \\{MPa\\} and 0.7 MPa. Four turbo expanders are employed, including one at 80 K because LN2 is not used in this system. Each expander drives a cold compressor, accompanying a generator brake by use of an induction motor. This provides very easy control. Variable nozzles are adopted to the expanders, and the number of valves are diminished as much as possible to reduce line pressure loss. Concerning a heat exchanger, we have examined a micro tube laminar flow heat exchanger which is compact and enables high efficiency at low temperature. This heat exchanger can reduce pressure loss greatly.

N. Saji; S. Nagai; H. Asakura; Y. Kaneko

1994-01-01T23:59:59.000Z

444

Equation of state and optical properties of warm dense helium  

Science Journals Connector (OSTI)

We investigate the physical properties of warm dense helium under the conditions found in the atmospheres of cool white dwarfs using both a chemical model and ab initio simulations. A chemical model is developed for the low-ionization limit that includes the species He, He+, He2+, and electrons, and interactions between them. The ab initio calculations consist in quantum molecular dynamics (QMD) simulations. We use the generalized gradient approximation (GGA) to calculate the equation of state and the electrical and optical properties within the linear response theory. We further use an exact exchange hybrid (PBE0) density functional as well as the GW approximation to estimate the uncertainties on the electrical and optical properties resulting from the GGA approximation. While both the chemical model and the QMD simulations are in excellent agreement with the measured equation of state, a qualitative discrepancy exists with the measured conductivity.

P. M. Kowalski, S. Mazevet, D. Saumon, and M. Challacombe

2007-08-10T23:59:59.000Z

445

Reactor Pressure Vessel Task of Light Water Reactor Sustainability Program:  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Reactor Pressure Vessel Task of Light Water Reactor Sustainability Reactor Pressure Vessel Task of Light Water Reactor Sustainability Program: Initial Assessment of Thermal Annealing Needs and Challenges Reactor Pressure Vessel Task of Light Water Reactor Sustainability Program: Initial Assessment of Thermal Annealing Needs and Challenges The most life-limiting structural component in light-water reactors (LWR) is the reactor pressure vessel (RPV) because replacement of the RPV is not considered a viable option at this time. LWR licenses are now being extended from 40y to 60y by the U.S. Nuclear Regulatory Commission (NRC) with intentions to extend licenses to 80y and beyond. The RPV materials exhibit varying degrees of sensitivity to irradiation-induced embrittlement (decreased toughness) , as shown in Fig. 1.1, and extending operation from

446

Reactor Pressure Vessel Task of Light Water Reactor Sustainability Program:  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Reactor Pressure Vessel Task of Light Water Reactor Sustainability Reactor Pressure Vessel Task of Light Water Reactor Sustainability Program: Milestone Report on Materials and Machining of Specimens for the ATR-2 Experiment Reactor Pressure Vessel Task of Light Water Reactor Sustainability Program: Milestone Report on Materials and Machining of Specimens for the ATR-2 Experiment The reactor pressure vessel (RPV) in a light-water reactor (LWR) represents the first line of defense against a release of radiation in case of an accident. Thus, regulations, which govern the operation of commercial nuclear power plants, require conservative margins of fracture toughness, both during normal operation and under accident scenarios. In the unirradiated condition, the RPV has sufficient fracture toughness such that failure is implausible under any postulated condition, including

447

Reactor for exothermic reactions  

DOE Patents (OSTI)

A liquid phase process is described for oligomerization of C[sub 4] and C[sub 5] isoolefins or the etherification thereof with C[sub 1] to C[sub 6] alcohols wherein the reactants are contacted in a reactor with a fixed bed acid cation exchange resin catalyst at an LHSV of 5 to 20, pressure of 0 to 400 psig and temperature of 120 to 300 F. Wherein the improvement is the operation of the reactor at a pressure to maintain the reaction mixture at its boiling point whereby at least a portion but less than all of the reaction mixture is vaporized. By operating at the boiling point and allowing a portion of the reaction mixture to vaporize, the exothermic heat of reaction is dissipated by the formation of more boil up and the temperature in the reactor is controlled.

Smith, L.A. Jr.; Hearn, D.; Jones, E.M. Jr.

1993-03-02T23:59:59.000Z

448

Thermionic Reactor Design Studies  

SciTech Connect

Paper presented at the 29th IECEC in Monterey, CA in August 1994. The present paper describes some of the author's conceptual designs and their rationale, and the special analytical techniques developed to analyze their (thermionic reactor) performance. The basic designs, first published in 1963, are based on single-cell converters, either double-ended diodes extending over the full height of the reactor core or single-ended diodes extending over half the core height. In that respect they are similar to the thermionic fuel elements employed in the Topaz-2 reactor subsequently developed in the Soviet Union, copies of which were recently imported by the U.S. As in the Topaz-2 case, electrically heated steady-state performance tests of the converters are possible before fueling.

Schock, Alfred

1994-08-01T23:59:59.000Z

449

The Role of Helium in the Outer Solar Atmosphere  

Science Journals Connector (OSTI)

We construct models of the outer solar atmosphere comprising the region from the mid-chromosphere and into the solar wind in order to study the force and energy balance in models with a significant helium abundance. The corona is created by dissipation of an energy flux from the Sun. The energy flux is lost as radiation from the top of the chromosphere and as gravitational and kinetic solar wind energy flux. We find that in models with significant ion heating of the extended corona most of the energy flux is lost in the solar wind. The ion temperatures are higher than the electron temperature in these models, and the ?-particle temperature is much higher than the proton temperature, so there is energy transfer from the ?-particle fluid to the protons and electrons, but this energy exchange between the different species is relatively small. To a fairly good approximation we can say that the energy flux deposited in the protons and ?-particles is lost as kinetic and gravitational energy flux in the proton and ?-particle flow. How this energy flux is divided between gravitational and kinetic energy flux (i.e., how large the particle fluxes and flow speeds are) depends upon details of the heating process. We also find that mixing processes in the chromosphere play an important role in determining the coronal helium abundance and the relative solar wind proton and ?-particle fluxes. Roughly speaking, we find that the relative ?-particle and proton fluxes are set by the degree of chromospheric mixing, while the speeds are set by the details of the coronal heating process.

V. H. Hansteen; E. Leer; T.

1997-01-01T23:59:59.000Z

450

Very High Temperature Reactor (VHTR) Deep Burn Core and Fuel Analysis -- Complete Design Selection for the Pebble Bed Reactor  

SciTech Connect

The Deep-Burn (DB) concept focuses on the destruction of transuranic nuclides from used light water reactor fuel. These transuranic nuclides are incorporated into TRISO coated fuel particles and used in gas-cooled reactors with the aim of a fractional fuel burnup of 60 to 70% in fissions per initial metal atom (FIMA). This high performance is expected through the use of multiple recirculation passes of the fuel in pebble form without any physical or chemical changes between passes. In particular, the concept does not call for reprocessing of the fuel between passes. In principle, the DB pebble bed concept employs the same reactor designs as the presently envisioned low-enriched uranium core designs, such as the 400 MWth Pebble Bed Modular Reactor (PBMR-400). Although it has been shown in the previous Fiscal Year (2009) that a PuO2 fueled pebble bed reactor concept is viable, achieving a high fuel burnup, while remaining within safety-imposed prescribed operational limits for fuel temperature, power peaking and temperature reactivity feedback coefficients for the entire temperature range, is challenging. The presence of the isotopes 239-Pu, 240-Pu and 241-Pu that have resonances in the thermal energy range significantly modifies the neutron thermal energy spectrum as compared to a standard, UO2-fueled core. Therefore, the DB pebble bed core exhibits a relatively hard neutron energy spectrum. However, regions within the pebble bed that are near the graphite reflectors experience a locally softer spectrum. This can lead to power and temperature peaking in these regions. Furthermore, a shift of the thermal energy spectrum with increasing temperature can lead to increased absorption in the resonances of the fissile Pu isotopes. This can lead to a positive temperature reactivity coefficient for the graphite moderator under certain operating conditions. The effort of this task in FY 2010 has focused on the optimization of the core to maximize the pebble discharge burnup level, while retaining its inherent safety characteristics. Using generic pebble bed reactor cores, this task will perform physics calculations to evaluate the capabilities of the pebble bed reactor to perform utilization and destruction of LWR used-fuel transuranics. The task will use established benchmarked models, and will introduce modeling advancements appropriate to the nature of the fuel considered (high TRU content and high burn-up).

B. Boer; A. M. Ougouag

2010-09-01T23:59:59.000Z

451

Diagnostics for hybrid reactors  

SciTech Connect

The Hybrid Reactor(HR) can be considered an attractive actinide-burner or a fusion assisted transmutation for destruction of transuranic(TRU) nuclear waste. The hybrid reactor has two important subsystems: the tokamak neutron source and the blanket which includes a fuel zone where the TRU are placed and a tritium breeding zone. The diagnostic system for a HR must be as simple and robust as possible to monitor and control the plasma scenario, guarantee the protection of the machine and monitor the transmutation.

Orsitto, Francesco Paolo [ENEA Unita' Tecnica Fusione , Associazione ENEA-EURATOM sulla Fusione C R Frascati v E Fermi 45 00044 Frascati (Italy)

2012-06-19T23:59:59.000Z

452

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

SciTech Connect

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

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

2009-03-01T23:59:59.000Z

453

THE EFFECTS OF CURVATURE AND EXPANSION ON HELIUM DETONATIONS ON WHITE DWARF SURFACES  

SciTech Connect

Accreted helium layers on white dwarfs have been highlighted for many decades as a possible site for a detonation triggered by a thermonuclear runaway. In this paper, we find the minimum helium layer thickness that will sustain a steady laterally propagating detonation and show that it depends on the density and composition of the helium layer, specifically {sup 12}C and {sup 16}O. Detonations in these thin helium layers have speeds slower than the Chapman-Jouget (CJ) speed from complete helium burning, v{sub CJ} = 1.5 10{sup 9} cm s{sup 1}. Though gravitationally unbound, the ashes still have unburned helium (?80% in the thinnest cases) and only reach up to heavy elements such as {sup 40}Ca, {sup 44}Ti, {sup 48}Cr, and {sup 52}Fe. It is rare for these thin shells to generate large amounts of {sup 56}Ni. We also find a new set of solutions that can propagate in even thinner helium layers when {sup 16}O is present at a minimum mass fraction of ?0.07. Driven by energy release from ? captures on {sup 16}O and subsequent elements, these slow detonations only create ashes up to {sup 28}Si in the outer detonated He shell. We close by discussing how the unbound helium burning ashes may create faint and fast 'Ia' supernovae as well as events with virtually no radioactivity, and speculate on how the slower helium detonation velocities impact the off-center ignition of a carbon detonation that could cause a Type Ia supernova in the double detonation scenario.

Moore, Kevin; Bildsten, Lars [Department of Physics, University of California, Santa Barbara, CA (United States); Townsley, Dean M. [Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL (United States)

2013-10-20T23:59:59.000Z

454

Structural materials for fusion reactors  

Science Journals Connector (OSTI)

Fusion Reactors will require specially engineered structural materials, which ... on safety considerations. The fundamental differences between fusion and other nuclear reactors arise due to the 14MeV neutronics ...

P. M. Raole; S. P. Deshpande

2009-04-01T23:59:59.000Z

455

Modeling of fission product release from HTR (high temperature reactor) fuel for risk analyses  

SciTech Connect

The US and FRG have developed methodologies to determine the performance of and fission product release from TRISO-coated fuel particles under postulated accident conditions. The paper presents a qualitative and quantitative comparison of US and FRG models. The models are those used by General Atomics (GA) and by the German Nuclear Research Center at Juelich (KFA/ISF). A benchmark calculation was performed for fuel temperatures predicted for the US Department of Energy sponsored Modular High Temperature Gas Cooled Reactor (MHTGR). Good agreement in the benchmark calculations supports the on-going efforts to verify and validate the independently developed codes of GA and KFA/ISF. This work was performed under the US/FRG Umbrella Agreement for Cooperation on Gas Cooled Reactor Development. 6 refs., 3 figs., 3 tabs.

Bolin, J.; Verfondern, K.; Dunn, T.; Kania, M.

1989-07-01T23:59:59.000Z

456

50 years of helium liquefaction at the MIT Cryogenic Engineering Laboratory  

Science Journals Connector (OSTI)

The evolution of the helium liquefaction facility of the MIT Cryogenic Engineering Laboratory and the history of its operation over the last 50 years are described. Professor Samuel C. Collins created the liquid-helium facility based on his earlier developments. The chronology of the laboratory helium liquefiers is given with a brief description of each one. The current facility based on the Model 2000 liquefier is described and operating experience is given. The reasons for the very high availability of the liquefaction system are developed.

Joseph L. Smith Jr.

2002-01-01T23:59:59.000Z

457

Laser-driven nanoplasmas in doped helium droplets: Local ignition and anisotropic expansion  

E-Print Network (OSTI)

Doping a helium nanodroplet with a tiny xenon cluster of a few atoms only, sparks complete ionization of the droplet at laser intensities below the ionization threshold of helium atoms. As a result, the intrinsically inert and transparent droplet turns into a fast and strong absorber of infrared light. Microscopic calculations reveal a two-step mechanism to be responsible for the dramatic change: Avalanche-like ionization of the helium atoms on a femtosecond time scale, driven by field ionization due to the quickly charged xenon core is followed by resonant absorption enabled by an unusual cigar-shaped nanoplasma within the droplet.

Mikaberidze, Alexey; Rost, Jan M

2009-01-01T23:59:59.000Z

458

Laser-Driven Nanoplasmas in Doped Helium Droplets: Local Ignition and Anisotropic Growth  

Science Journals Connector (OSTI)

Doping a helium nanodroplet with only a tiny xenon cluster of a few atoms sparks complete ionization of the droplet at laser intensities below the ionization threshold of helium atoms. As a result, the intrinsically inert and transparent droplet turns into a fast and strong absorber of infrared light. Microscopic calculations reveal a two-step mechanism to be responsible for the dramatic change: Avalanchelike ionization of the helium atoms on a femtosecond time scale, driven by field ionization due to the quickly charged xenon core, is followed by resonant absorption enabled by an unusual cigar-shaped nanoplasma within the droplet.

Alexey Mikaberidze, Ulf Saalmann, and Jan M. Rost

2009-03-25T23:59:59.000Z

459

Coal-fueled diesels for modular power generation  

SciTech Connect

Interest in coal-fueled heat engines revived after the sharp increase in the prices of natural gas and petroleum in the 1970`s. Based on the success of micronized coal water slurry combustion tests in an engine in the 1980`s, Morgantown Energy Technology Center (METC) of the US Department of Energy. initiated several programs for the development of advanced coal-fueled diesel and gas turbine engines for use in cogeneration, small utilities, industrial applications and transportation. Cooper-Bessemer and Arthur D. Little have been developing technology since 1985, under the sponsor of METC, to enable coal water slurry (CWS) to be utilized in large bore, medium-speed diesel engines. Modular power generation applications in the 10--100 MW size (each plant typically using from two to eight engines) are the target applications for the late 1990`s and beyond when, according to the US DOE and other projections, oil and natural gas prices are expected to escalate much more rapidly compared to the price of coal. As part of this program over 7.50 hours of prototype engine operation has been achieved on coal water slurry (CWS), including over 100 hours operation of a six-cylinder full scale engine with Integrated Emissions Control System in 1993. In this paper, the authors described the project cost of the CWS fuel used, the heat rate of the engine operating on CWS, the projected maintenance cost for various engine components, and the demonstrated low emissions characteristics of the coal diesel system.

Wilson, R.P. [Little (Arthur D.), Inc., Cambridge, MA (United States); Rao, A.K. [Cooper-Bessemer Reciprocating, Grove City, PA (United States); Smith, W.C. [Department of Energy, Morgantown, WV (United States). Morgantown Energy Technology Center

1993-11-01T23:59:59.000Z

460

Geometric Modularity in the Thermal Modeling of Solar Steam Turbines  

Science Journals Connector (OSTI)

Abstract To optimize the start-up schedules of steam turbines operating in concentrating solar power plants, accurate predictions of the temperatures within the turbine are required. In previous work by the authors, thermal models of steam turbines have been developed and validated for parabolic trough solar power plant applications. Building on these results, there is an interest to increase the adaptability of the models with respect to different turbine geometries due to the growing trend of having larger steam turbines in parabolic trough and solar tower power plants. In this work, a modular geometric approach has been developed and compared against both the previous modeling approach and 96h of measured data from an operational parabolic trough power plant. Results show a large degree of agreement with respect to the measured data in spite of the different detail levels. The new model allows for simple and fast prediction of the thermal behavior of different steam turbine sizes and geometries, which is expected to be of significant importance for future concentrating solar power plants.

M. Topel; J. Spelling; M. Jcker; B. Laumert

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modular helium reactor" from the National Library of EnergyBeta (NLEBeta).
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461

Reactor Materials | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Benefits Crosscutting Technology Development Reactor Materials Advanced Sensors and Instrumentation Proliferation and Terrorism Risk Assessment Advanced Methods for Manufacturing...

462

Reactor operation safety information document  

SciTech Connect

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

Not Available

1990-01-01T23:59:59.000Z

463

High-temperature low-cycle fatigue and tensile properties of Hastelloy X and alloy 617 in air and HTGR-helium  

SciTech Connect

Results of strain controlled fatigue and tensile tests are presented for two nickel base solution hardened alloys which are reference structural alloys for use in several high temperature gas cooled reactor concepts. These alloys, Hastelloy X Inconel 617, were tested at temperatures ranging from room temperature to 871/sup 0/C in air and impure helium. Materials were tested in the solution annealed as well as in the pre-aged condition where aging consisted of isothermal exposure at one of several temperatures for periods of up to 20,000 h. Comparisons are also given between the strain controlled fatigue lives of these alloys and several other commonly used alloys all tested at 538/sup 0/C.

Strizak, J.P.; Brinkman, C.R.; Rittenhouse, P.L.

1981-01-01T23:59:59.000Z

464

Relationship of H/sub 2/O and CH/sub 4/ supply rates in HTGR helium to the carburization of Hastelloy-X and alloy 800H  

SciTech Connect

A detailed study of the carburization of Hastelloy-X and alloy 800H in high-temperature gas-cooled reactor helium was made to determine the cause of the wide variability of data generated in retorts. Data for 1000/sup 0/C and 2500-h exposure show that up to an order of magnitude difference in the carburization levels can be caused by changes in the flow rate of the test gas and/or the position of the corrosion specimen in the gas stream. The results are unambiguously explained by the parameters S(H/sub 2/O) and S(CH/sub 4/), the supply rates of water and methane, respectively.

Inouye, H.

1984-08-01T23:59:59.000Z

465

Fossil fuel furnace reactor  

DOE Patents (OSTI)

A fossil fuel furnace reactor is provided for simulating a continuous processing plant with a batch reactor. An internal reaction vessel contains a batch of shale oil, with the vessel having a relatively thin wall thickness for a heat transfer rate effective to simulate a process temperature history in the selected continuous processing plant. A heater jacket is disposed about the reactor vessel and defines a number of independent controllable temperature zones axially spaced along the reaction vessel. Each temperature zone can be energized to simulate a time-temperature history of process material through the continuous plant. A pressure vessel contains both the heater jacket and the reaction vessel at an operating pressure functionally selected to simulate the continuous processing plant. The process yield from the oil shale may be used as feedback information to software simulating operation of the continuous plant to provide operating parameters, i.e., temperature profiles, ambient atmosphere, operating pressure, material feed rates, etc., for simulation in the batch reactor.

Parkinson, William J. (Los Alamos, NM)

1987-01-01T23:59:59.000Z

466

Transport reactor development status  

SciTech Connect

This project is part of METC`s Power Systems Development Facility (PSDF) located at Wilsonville, Alabama. The primary objective of the Advanced Gasifier module is to produce vitiated gases for intermediate-term testing of Particulate Control Devices (PCDs). The Transport reactor potentially allows particle size distribution, solids loading, and particulate characteristics in the off-gas stream to be varied in a number of ways. Particulates in the hot gases from the Transport reactor will be removed in the PCDs. Two PCDs will be initially installed in the module; one a ceramic candle filter, the other a granular bed filter. After testing of the initial PCDs they will be removed and replaced with PCDs supplied by other vendors. A secondary objective is to verify the performance of a Transport reactor for use in advanced Integrated Gasification Combined Cycle (IGCC), Integrated Gasification Fuel Cell (IG-FC), and Pressurized Combustion Combined Cycle (PCCC) power generation units. This paper discusses the development of the Transport reactor design from bench-scale testing through pilot-scale testing to design of the Process Development Unit (PDU-scale) facility at Wilsonville.

Rush, R.E.; Fankhanel, M.O.; Campbell, W.M.

1994-10-01T23:59:59.000Z

467

Thermal Reactor Safety  

SciTech Connect

Information is presented concerning fire risk and protection; transient thermal-hydraulic analysis and experiments; class 9 accidents and containment; diagnostics and in-service inspection; risk and cost comparison of alternative electric energy sources; fuel behavior and experiments on core cooling in LOCAs; reactor event reporting analysis; equipment qualification; post facts analysis of the TMI-2 accident; and computational methods.

Not Available

1980-06-01T23:59:59.000Z

468

NETL - Chemical Looping Reactor  

ScienceCinema (OSTI)

NETL's Chemical Looping Reactor unit is a high-temperature integrated CLC process with extensive instrumentation to improve computational simulations. A non-reacting test unit is also used to study solids flow at ambient temperature. The CLR unit circulates approximately 1,000 pounds per hour at temperatures around 1,800 degrees Fahrenheit.

None

2014-06-26T23:59:59.000Z

469

Modular Extrapolation Approach for Crop LCA MEXALCA: Global Warming Potential of Different Crops and its Relationship to the Yield  

Science Journals Connector (OSTI)

MEXALCA (Modular EXtrapolation of Agricultural LCA) extrapolates crop inventory data and impacts from an original country inventory to all producing countries worldwide. This allows estimates of worldwide mean...

Thomas Nemecek; Karin Weiler

2011-01-01T23:59:59.000Z

470

Hybrid reliability model for nuclear reactor safety system  

Science Journals Connector (OSTI)

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

Steven Verlinden; Geert Deconinck; Bernard Coup

2012-01-01T23:59:59.000Z

471

Reliability analysis for Atucha II reactor protection system signals  

Science Journals Connector (OSTI)

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

Jose Luis Roca

1996-01-01T23:59:59.000Z

472

On the mechanism of electromagnetic microwave absorption in superfluid helium  

SciTech Connect

In experiments on electromagnetic (EM) wave absorption in the microwave range in superfluid (SF) helium [1-3], a narrow EM field absorption line with a width on the order of (20-200) kHz was observed against the background of a wide absorption band with a width of 30-40 GHz at frequencies f{sub 0} Almost-Equal-To 110-180 GHz corresponding to the roton gap energy {Delta}{sub r}(T) in the temperature range 1.4-2.2 K. Using the so-called flexoelectric mechanism of polarization of helium atoms ({sup 4}He) in the presence of density gradients in SF helium (HeII), we show that nonresonance microwave absorption in the frequency range 170-200 GHz can be due to the existence of time-varying local density gradients produced by roton excitations in the bulk HeII. The absorption bandwidth is determined by the roton-roton scattering time in an equilibrium Boltzmann gas of rotons, which is t{sub r-r} Almost-Equal-To 3.4 Multiplication-Sign 10{sup -11} s at T = 1.4 K and decreases upon heating. We propose that the anomalously narrow microwave resonance absorption line in HeII at the roton frequency f{sub 0}(T) = {Delta}r(T)/2{pi}h appears due to the following two factors: (i) the discrete structure of the spectrum of the surface EM resonator modes in the form of a periodic sequence of narrow peaks and (ii) the presence of a stationary dipole layer in HeII near the resonator surface, which forms due to polarization of {sup 4}He atoms under the action of the density gradient associated with the vanishing of the density of the SF component at the solid wall. For this reason, the relaxation of nonequilibrium rotons generated in such a surface dipole layer is strongly suppressed, and the shape and width of the microwave resonance absorption line are determined by the roton density of states, which has a sharp peak at the edge of the roton gap in the case of weak dissipation. The effective dipole moments of rotons in the dipole layer can be directed either along or across the normal to the resonator surface, which explains the experimentally observed symmetric doublet splitting of the resonance absorption line in an external dc electric field perpendicular to the resonator surface. We show that negative absorption (induced emission) of EM field quanta observed after triggering a Kapitza 'heat gun' occurs when the occupation numbers for roton states due to 'pumping' of rotons exceed the occupation numbers of EM field photons in the resonator.

Pashitskii, E. A., E-mail: pashitsk@iop.kiev.ua; Pentegov, V. I. [National Academy of Sciences of Ukraine, Institute of Physics (Ukraine)

2012-08-15T23:59:59.000Z

473

Reactor vessel support system. [LMFBR  

DOE Patents (OSTI)

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

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

1980-05-09T23:59:59.000Z

474

Advanced Instrumentation and Control Methods for Small and Medium Reactors with IRIS Demonstration  

SciTech Connect

Development and deployment of small-scale nuclear power reactors and their maintenance, monitoring, and control are part of the mission under the Small Modular Reactor (SMR) program. The objectives of this NERI-consortium research project are to investigate, develop, and validate advanced methods for sensing, controlling, monitoring, diagnosis, and prognosis of these reactors, and to demonstrate the methods with application to one of the proposed integral pressurized water reactors (IPWR). For this project, the IPWR design by Westinghouse, the International Reactor Secure and Innovative (IRIS), has been used to demonstrate the techniques developed under this project. The research focuses on three topical areas with the following objectives. Objective 1 - Develop and apply simulation capabilities and sensitivity/uncertainty analysis methods to address sensor deployment analysis and small grid stability issues. Objective 2 - Develop and test an autonomous and fault-tolerant control architecture and apply to the IRIS system and an experimental flow control loop, with extensions to multiple reactor modules, nuclear desalination, and optimal sensor placement strategy. Objective 3 - Develop and test an integrated monitoring, diagnosis, and prognosis system for SMRs using the IRIS as a test platform, and integrate process and equipment monitoring (PEM) and process and equipment prognostics (PEP) toolboxes. The research tasks are focused on meeting the unique needs of reactors that may be deployed to remote locations or to developing countries with limited support infrastructure. These applications will require smaller, robust reactor designs with advanced technologies for sensors, instrumentation, and control. An excellent overview of SMRs is described in an article by Ingersoll (2009). The article refers to these as deliberately small reactors. Most of these have modular characteristics, with multiple units deployed at the same plant site. Additionally, the topics focus on meeting two of the eight needs outlined in the recently published 'Technology Roadmap on Instrumentation, Control, and Human-Machine Interface (ICHMI) to Support DOE Advanced Nuclear Energy Programs' which was created 'to provide a systematic path forward for the integration of new ICHMI technologies in both near-term and future nuclear power plants and the reinvigoration of the U.S. nuclear ICHMI community and capabilities.' The research consortium is led by The University of Tennessee (UT) and is focused on three interrelated topics: Topic 1 (simulator development and measurement sensitivity analysis) is led by Dr. Mike Doster with Dr. Paul Turinsky of North Carolina State University (NCSU). Topic 2 (multivariate autonomous control of modular reactors) is led by Dr. Belle Upadhyaya of the University of Tennessee (UT) and Dr. Robert Edwards of Penn State University (PSU). Topic 3 (monitoring, diagnostics, and prognostics system development) is led by Dr. Wes Hines of UT. Additionally, South Carolina State University (SCSU, Dr. Ken Lewis) participated in this research through summer interns, visiting faculty, and on-campus research projects identified throughout the grant period. Lastly, Westinghouse Science and Technology Center (Dr. Mario Carelli) was a no-cost collaborator and provided design information related to the IRIS demonstration platform and defining needs that may be common to other SMR designs. The results of this research are reported in a six-volume Final Report (including the Executive Summary, Volume 1). Volumes 2 through 6 of the report describe in detail the research and development under the topical areas. This volume serves to introduce the overall NERI-C project and to summarize the key results. Section 2 provides a summary of the significant contributions of this project. A list of all the publications under this project is also given in Section 2. Section 3 provides a brief summary of each of the five volumes (2-6) of the report. The contributions of SCSU are described in Section 4, including a summary of undergraduate research exper

J. Wesley Hines; Belle R. Upadhyaya; J. Michael Doster; Robert M. Edwards; Kenneth D. Lewis; Paul Turinsky; Jamie Coble

2011-05-31T23:59:59.000Z

475

Cryogenic system component development for the fusion experimental reactor at JAERI  

SciTech Connect

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

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

1986-01-01T23:59:59.000Z

476

Helium isotopes in geothermal systems- Iceland, The Geysers, Raft River and  

Open Energy Info (EERE)

Helium isotopes in geothermal systems- Iceland, The Geysers, Raft River and Helium isotopes in geothermal systems- Iceland, The Geysers, Raft River and Steamboat Springs Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Helium isotopes in geothermal systems- Iceland, The Geysers, Raft River and Steamboat Springs Details Activities (3) Areas (3) Regions (0) Abstract: Helium isotope ratios have been measured in geothermal fluids from Iceland, The Geysers, Raft River, Steamboat Springs and Hawaii. These ratios have been interpreted in terms of the processes which supply He in distinct isotopic ratios (i.e. magmatic He, ~10 Ra; atmospheric He, R,sub>a; and crustal He, ~0.1 Ra) and in terms of the processes which can alter the isotopic ratio (hydrologic mixing, U-Th series alpha production and weathering release of crustal He, magma aging and

477

Helium Isotopes In Geothermal And Volcanic Gases Of The Western United  

Open Energy Info (EERE)

Helium Isotopes In Geothermal And Volcanic Gases Of The Western United Helium Isotopes In Geothermal And Volcanic Gases Of The Western United States, I, Regional Variability And Magmatic Origin Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Helium Isotopes In Geothermal And Volcanic Gases Of The Western United States, I, Regional Variability And Magmatic Origin Details Activities (1) Areas (1) Regions (0) Abstract: Helium isotope ratios in gases of thirty hot springs and geothermal wells and of five natural gas wells