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1

TRANSP simulations of International Thermonuclear Experimental Reactor plasmas  

E-Print Network [OSTI]

TRANSP simulations of International Thermonuclear Experimental Reactor plasmas R. V. Budny, D. C-consistent models for plasmas within the separatrix surface in the International Thermonuclear Experimental Reactor. INTRODUCTION One of the goals for the International Thermonuclear Experimental Reactor ITER is the production

Budny, Robert

2

Industrial opportunities on the International Thermonuclear Experimental Reactor (ITER) project  

SciTech Connect (OSTI)

Industry has been a long-term contributor to the magnetic fusion program, playing a variety of important roles over the years. Manufacturing firms, engineering-construction companies, and the electric utility industry should all be regarded as legitimate stakeholders in the fusion energy program. In a program focused primarily on energy production, industry`s future roles should follow in a natural way, leading to the commercialization of the technology. In a program focused primarily on science and technology, industry`s roles, in the near term, should be, in addition to operating existing research facilities, largely devoted to providing industrial support to the International Thermonuclear Experimental Reactor (ITER) Project. Industrial opportunities on the ITER Project will be guided by the amount of funding available to magnetic fusion generally, since ITER is funded as a component of that program. The ITER Project can conveniently be discussed in terms of its phases, namely, the present Engineering Design Activities (EDA) phase, and the future (as yet not approved) construction phase. 2 refs., 3 tabs.

Ellis, W.R. [Raytheon Engineers and Constructors, New York, NY (United States)

1996-12-01T23:59:59.000Z

3

ITER: The International Thermonuclear Experimental Reactor and the nuclear weapons proliferation implications of thermonuclear-fusion energy  

E-Print Network [OSTI]

This paper contains two parts: (I) A list of "points" highlighting the strategic-political and military-technical reasons and implications of the very probable siting of ITER (the International Thermonuclear Experimental Reactor) in Japan, which should be confirmed sometimes in early 2004. (II) A technical analysis of the nuclear weapons proliferation implications of inertial- and magnetic-confinement fusion systems substantiating the technical points highlighted in the first part, and showing that while full access to the physics of thermonuclear weapons is the main implication of ICF, full access to large-scale tritium technology is the main proliferation impact of MCF. The conclusion of the paper is that siting ITER in a country such as Japan, which already has a large separated-plutonium stockpile, and an ambitious laser-driven ICF program (comparable in size and quality to those of the United States or France) will considerably increase its latent (or virtual) nuclear weapons proliferation status, and fo...

Gsponer, A; Gsponer, Andre; Hurni, Jean-Pierre

2004-01-01T23:59:59.000Z

4

Inexpensive Mini Thermonuclear Reactor  

E-Print Network [OSTI]

This proposed design for a mini thermonuclear reactor uses a method based upon a series of important innovations. A cumulative explosion presses a capsule with nuclear fuel up to 100 thousands of atmospheres, the explosive electric generator heats the capsule/pellet up to 100 million degrees and a special capsule and a special cover which keeps these pressure and temperature in capsule up to 0.001 sec. which is sufficient for Lawson criteria for ignition of thermonuclear fuel. Major advantages of these reactors/bombs is its very low cost, dimension, weight and easy production, which does not require a complex industry. The mini thermonuclear bomb can be delivered as a shell by conventional gun (from 155 mm), small civil aircraft, boat or even by an individual. The same method may be used for thermonuclear engine for electric energy plants, ships, aircrafts, tracks and rockets. Key words: Thermonuclear mini bomb, thermonuclear reactor, nuclear energy, nuclear engine,

Alexander Bolonkin; Alexander Bolonkin

5

The Japan Times Printer Friendly Articles France has won the competition to host the International Thermonuclear Experimental Reactor (ITER), the world's first nuclear-  

E-Print Network [OSTI]

the International Thermonuclear Experimental Reactor (ITER), the world's first nuclear- fusion reactor. Japan fought wins by withdrawing ITER bid Thermonuclear fusion utilizes the same process that powers the sun

6

ITER: The International Thermonuclear Experimental Reactor and the Nuclear Weapons Proliferation Implications of Thermonuclear-Fusion Energy Systems  

E-Print Network [OSTI]

This paper contains two parts: (I) A list of “points ” highlighting the strategic-political and militarytechnical reasons and implications of the very probable siting of ITER (the International Thermonuclear Experimental Reactor) in Japan, which should be confirmed sometimes in early 2004. (II) A technical analysis of the nuclear weapons proliferation implications of inertial- and magnetic-confinement fusion systems substantiating the technical points highlighted in the first part, and showing that while full access to the physics of thermonuclear weapons is the main implication of ICF, full access to large-scale tritium technology is the main proliferation impact of MCF. The conclusion of the paper is that siting ITER in a country such as Japan, which already has a large separated-plutonium stockpile, and an ambitious laser-driven ICF program (comparable in size and quality to those of the United States or France) will considerably increase its latent (or virtual) nuclear weapons proliferation status, and foster further nuclear proliferation throughout the world. The safety and environmental problems related to the operation of largescale fusion facilities such as ITER (which contain massive amounts of hazardous and/or radioactive materials such as tritium, lithium, and beryllium, as well as neutron-activated structural materials) are not addressed in this paper.

André Gsponer; Jean-pierre Hurni

2004-01-01T23:59:59.000Z

7

US ITER (International Thermonuclear Experimental Reactor) shield and blanket design activities  

SciTech Connect (OSTI)

This paper summarizes nuclear-related work in support of the US effort for the International Thermonuclear Experimental Reactor (ITER) Study. Primary tasks carried out during the past year include design improvements of the inboard shield developed for the TIBER concept, scoping studies of a variety of tritium breeding blanket options, development of necessary design guidelines and evaluation criteria for the blanket options, further safety considerations related to nuclear components, and issues regarding structural materials for an ITER device. The blanket concepts considered are the aqueous/Li salt solution, a water-cooled, solid breeder blanket, a helium-cooled, solid-breeder blanket, a blanket cooled by helium containing lithium-bearing particulates, and a blanket concept based on breeding tritium from He/sup 3/. 1 ref., 2 tabs.

Baker, C.C.

1988-08-01T23:59:59.000Z

8

Review of the International Thermonuclear Experimental Reactor (ITER) detailed design report  

SciTech Connect (OSTI)

Dr. Martha Krebs, Director, Office of Energy Research at the US Department of Energy (DOE), wrote to the Fusion Energy Sciences Advisory Committee (FESAC), in letters dated September 23 and November 6, 1996, requesting that FESAC review the International Thermonuclear Experimental Reactor (ITER) Detailed Design Report (DDR) and provide its view of the adequacy of the DDR as part of the basis for the United States decision to enter negotiations with the other interested Parties regarding the terms and conditions for an agreement for the construction, operations, exploitation and decommissioning of ITER. The letter from Dr. Krebs, referred to as the Charge Letter, provided context for the review and a set of questions of specific interest.

NONE

1997-04-18T23:59:59.000Z

9

03/01/2006 09:51 AMLoading "People's Daily Online --Chinese experimental thermonuclear reactor on discharge test in July" Page 1 of 1http://english.people.com.cn/200603/01/print20060301_247035.html  

E-Print Network [OSTI]

03/01/2006 09:51 AMLoading "People's Daily Online -- Chinese experimental thermonuclear reactor experimental thermonuclear reactor on discharge test in July China's new generation experimental Tokamak fusion and the former Soviet Union launched a 10 billion- euro ambitious plan, the International Thermonuclear

10

Beryllium fabrication/cost assessment for ITER (International Thermonuclear Experimental Reactor)  

SciTech Connect (OSTI)

A fabrication and cost estimate of three possible beryllium shapes for the International Thermonuclear Experimental Reactor (ITER) blanket is presented. The fabrication method by hot pressing (HP), cold isostatic pressing plus sintering (CIP+S), cold isostatic pressing plus sintering plus hot isostatic pressing (CIP+S+HIP), and sphere production by atomization or rotary electrode will be discussed. Conventional hot pressing blocks of beryllium with subsequent machining to finished shapes can be more expensive than production of a net shape by cold isostatic pressing and sintering. The three beryllium shapes to be considered here and proposed for ITER are: (1) cubic blocks (3 to 17 cm on an edge), (2) tubular cylinders (33 to 50 mm i.d. by 62 mm o.d. by 8 m long), and (3) spheres (1--5 mm dia.). A rough cost estimate of the basic shape is presented which would need to be refined if the surface finish and tolerances required are better than the sintering process produces. The final cost of the beryllium in the blanket will depend largely on the machining and recycling of beryllium required to produce the finished product. The powder preparation will be discussed before shape fabrication. 10 refs., 6 figs.

Beeston, J.M. (Beeston (J.M.), Garrison, UT (USA)); Longhurst, G.R. (EG and G Idaho, Inc., Idaho Falls, ID (USA)); Parsonage, T. (Brush Wellman, Inc., Elmore, OH (USA))

1990-06-01T23:59:59.000Z

11

Toroidal field coil replacement study for the International Thermonuclear Experimental Reactor (ITER)  

SciTech Connect (OSTI)

The objective of this study is to develop an estimate of the time required to replace a failed toroidal field (TF) coil in the International Thermonuclear Experimental Reactor (ITER). This estimate is based on the current ITER design which resulted from the Conceptual Design Activities began in spring of 1988 and ending in December 1990. Although the TF Coils in ITER are designated permanent components and expected to last the life of the plant, the history of failures of large coils in fusion devices has prompted an assessment of the down time that might be required for replacement of a failed TF coil in ITER. The difficulty of replacement of a TF Coil in ITER is compounded by the large physical size of ITER, and the radiation fields which necessitate the use of remote handling equipment for most maintenance activities. Since 10 out of 16 TF coils are adjacent to either a Neutral Beam Injector (NBI) port or a remote handling (RH) port, it is probable that a failed TF Coil will be in one of these inconvenient locations. For this study, TF coil number 3 is assumed to fail and its replacement will be evaluated as a typical case. TF coil number 3 is located between a remote handling port ({number sign}3) and a port allocated to the lower hybrid ({number sign}4).

Not Available

1991-08-01T23:59:59.000Z

12

Toroidal field coil replacement study for the International Thermonuclear Experimental Reactor (ITER)  

SciTech Connect (OSTI)

The objective of this study is to develop an estimate of the time required to replace a failed toroidal field (TF) coil in the International Thermonuclear Experimental Reactor (ITER). This estimate is based on the current ITER design which resulted from the Conceptual Design Activities began in spring of 1988 and ending in December 1990. Although the TF Coils in ITER are designated permanent components and expected to last the life of the plant, the history of failures of large coils in fusion devices has prompted an assessment of the down time that might be required for replacement of a failed TF coil in ITER. The difficulty of replacement of a TF Coil in ITER is compounded by the large physical size of ITER, and the radiation fields which necessitate the use of remote handling equipment for most maintenance activities. Since 10 out of 16 TF coils are adjacent to either a Neutral Beam Injector (NBI) port or a remote handling (RH) port, it is probable that a failed TF Coil will be in one of these inconvenient locations. For this study, TF coil number 3 is assumed to fail and its replacement will be evaluated as a typical case. TF coil number 3 is located between a remote handling port ({number_sign}3) and a port allocated to the lower hybrid ({number_sign}4).

Not Available

1991-08-01T23:59:59.000Z

13

Economic impacts on the United States of siting decisions for the international thermonuclear experimental reactor  

SciTech Connect (OSTI)

This report presents the results of a study that examines and compares the probable short-term economic impacts of the International Thermonuclear Experimental Reactor (ITER) on the United States (U.S.) if (1) ITER were to be sited in the U.S., or (2) ITER were to be sited in one of the other countries that, along with the U.S., is currently participating in the ITER program. Life-cycle costs associated with ITER construction, operation, and decommissioning are analyzed to assess their economic impact. A number of possible U.S. host and U.S. non-host technology and cost-sharing arrangements with the other ITER Parties are examined, although cost-sharing arrangements and the process by which the Parties will select a host country and an ITER site remain open issues. Both national and local/regional economic impacts, as measured by gross domestic product, regional output, employment, net exports, and income, are considered. These impacts represent a portion of the complex, interrelated set of economic considerations that characterize U.S. host and U.S. non-host participation in ITER. A number of other potentially important economic and noneconomic considerations are discussed qualitatively.

Peerenboom, J.P.; Hanson, M.E.; Huddleston, J.R. [and others

1996-08-01T23:59:59.000Z

14

Thermonuclear Reflect AB-Reactor  

E-Print Network [OSTI]

The author offers a new kind of thermonuclear reflect reactor. The remarkable feature of this new reactor is a three net AB reflector, which confines the high temperature plasma. The plasma loses part of its energy when it contacts with the net but this loss can be compensated by an additional permanent plasma heating. When the plasma is rarefied (has a small density), the heat flow to the AB reflector is not large and the temperature in the triple reflector net is lower than 2000 - 3000 K. This offered AB-reactor has significantly less power then the currently contemplated power reactors with magnetic or inertial confinement (hundreds-thousands of kW, not millions of kW). But it is enough for many vehicles and ships and particularly valuable for tunnelers, subs and space apparatus, where air to burn chemical fuel is at a premium or simply not available. The author has made a number of innovations in this reactor, researched its theory, developed methods of computation, made a sample computation of typical project. The main point of preference for the offered reactor is its likely cheapness as a power source. Key words: Micro-thermonuclear reactor, Multi-reflex AB-thermonuclear reactor, Self-magnetic AB-thermonuclear reactor, aerospace thermonuclear engine.

Alexander Bolonkin

2008-03-26T23:59:59.000Z

15

Iran cannot have claimed to be building a thermonuclear reactor -To build a thermonuclear reactor by its own efforts is a task absolutely beyond Iran's  

E-Print Network [OSTI]

Iran cannot have claimed to be building a thermonuclear reactor - expert To build a thermonuclear misunderstood." Work to create a thermonuclear reactor has been pursued in all leading countries for several experimental thermonuclear reactor ITER in France. The project involves the European Union, America, Russia

16

First operation with the JET International Thermonuclear Experimental Reactor-like wall  

SciTech Connect (OSTI)

To consolidate International Thermonuclear Experimental Reactor (ITER) design choices and prepare for its operation, Joint European Torus (JET) has implemented ITER's plasma facing materials, namely, Be for the main wall and W in the divertor. In addition, protection systems, diagnostics, and the vertical stability control were upgraded and the heating capability of the neutral beams was increased to over 30 MW. First results confirm the expected benefits and the limitations of all metal plasma facing components (PFCs) but also yield understanding of operational issues directly relating to ITER. H-retention is lower by at least a factor of 10 in all operational scenarios compared to that with C PFCs. The lower C content (? factor 10) has led to much lower radiation during the plasma burn-through phase eliminating breakdown failures. Similarly, the intrinsic radiation observed during disruptions is very low, leading to high power loads and to a slow current quench. Massive gas injection using a D{sub 2}/Ar mixture restores levels of radiation and vessel forces similar to those of mitigated disruptions with the C wall. Dedicated L-H transition experiments indicate a 30% power threshold reduction, a distinct minimum density, and a pronounced shape dependence. The L-mode density limit was found to be up to 30% higher than for C allowing stable detached divertor operation over a larger density range. Stable H-modes as well as the hybrid scenario could be re-established only when using gas puff levels of a few 10{sup 21} es{sup ?1}. On average, the confinement is lower with the new PFCs, but nevertheless, H factors up to 1 (H-Mode) and 1.3 (at ?{sub N}?3, hybrids) have been achieved with W concentrations well below the maximum acceptable level.

Neu, R. [EFDA-CSU, Boltzmannstr. 2, 85748 Garching (Germany) [EFDA-CSU, Boltzmannstr. 2, 85748 Garching (Germany); Max-Planck-Institut für Plasmaphysik, Euratom Association, Boltzmannstr. 2, 85748 Garching (Germany); Arnoux, G.; Beurskens, M.; Challis, C.; Giroud, C.; Lomas, P.; Maddison, G.; Matthews, G.; Mayoral, M.-L.; Meigs, A.; Rimini, F. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom)] [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Bobkov, V.; Dux, R.; Hobirk, J.; Lang, P.; Maggi, C.; Pütterich, T.; Sertoli, M.; Sieglin, B. [Max-Planck-Institut für Plasmaphysik, Euratom Association, Boltzmannstr. 2, 85748 Garching (Germany)] [Max-Planck-Institut für Plasmaphysik, Euratom Association, Boltzmannstr. 2, 85748 Garching (Germany); Brezinsek, S. [IEK-4, Association EURATOM/Forschungszentrum Jülich GmbH, Jülich 52425 (Germany)] [IEK-4, Association EURATOM/Forschungszentrum Jülich GmbH, Jülich 52425 (Germany); and others

2013-05-15T23:59:59.000Z

17

ITER: The International Thermonuclear Experimental Reactor and the Nuclear Weapons Proliferation  

E-Print Network [OSTI]

militarytechnical reasons and implications of the very probable siting of ITER (the International Thermonuclear

André Gsponer; Jean-pierre Hurni

2004-01-01T23:59:59.000Z

18

Thermonuclear reactor may begin to be built 2004 21.02.2004, 00.55  

E-Print Network [OSTI]

Thermonuclear reactor may begin to be built 2004 21.02.2004, 00.55 MOSCOW, February 20 (Itar-Tass) -- Construction of what may become the world's first-ever thermonuclear experimental reactor (ITER) may begin Institute, which developed the thermonuclear reactor, Yevgeny Velikhov said. The Russian panel at the Vienna

19

ITER --"INTERNATIONAL THERMONUCLEAR EXPERIMENTAL RESEARCH PROGRAM".  

E-Print Network [OSTI]

ITER -- "INTERNATIONAL THERMONUCLEAR EXPERIMENTAL RESEARCH PROGRAM". ORGANIZATION TO DIRECT WORLD plasmas and thermonuclear burn processes (cost -$1.5-36)2. (2) An expanded, more ambitious international Thermonuclear Experimental Research Program" by L. J. Perkins #12;NORMAL-CONDUCTING COPPER OPTIONS FOR THE ITER

20

PUBLISHED VERSION Design, performance, and grounding aspects of the International Thermonuclear Experimental  

E-Print Network [OSTI]

PUBLISHED VERSION Design, performance, and grounding aspects of the International Thermonuclear, performance, and grounding aspects of the International Thermonuclear Experimental Reactor ion cyclotron range Thermonuclear Experimental Reactor ion cyclotron range of frequencies antenna F. Durodie,1,a) P. Dumortier,1 M

Note: This page contains sample records for the topic "thermonuclear experimental 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

Micro -Thermonuclear AB-Reactors for Aerospace  

E-Print Network [OSTI]

The author offers several innovations that he first suggested publicly early in 1983 for the AB multi-reflex engine, space propulsion, getting energy from plasma, etc. (see: A. Bolonkin, Non-Rocket Space Launch and Flight, Elsevier, London, 2006, Chapters 12, 3A). It is the micro-thermonuclear AB-Reactors. That is new micro-thermonuclear reactor with very small fuel pellet that uses plasma confinement generated by multi-reflection of laser beam or its own magnetic field. The Lawson criterion increases by hundreds of times. The author also suggests a new method of heating the power-making fuel pellet by outer electric current as well as new direct method of transformation of ion kinetic energy into harvestable electricity. These offered innovations dramatically decrease the size, weight and cost of thermonuclear reactor, installation, propulsion system and electric generator. Non-industrial countries can produce these researches and constructions. Currently, the author is researching the efficiency of these innovations for two types of the micro-thermonuclear reactors: multi-reflection reactor (ICF) and self-magnetic reactor (MCF).

Alexander Bolonkin

2007-01-08T23:59:59.000Z

22

New AB-Thermonuclear Reactor for Aerospace  

E-Print Network [OSTI]

There are two main methods of nulcear fusion: inertial confinement fusion (ICF) and magnetic confinement fusion (MCF). Existing thermonuclear reactors are very complex, expensive, large, and heavy. They cannot achieve the Lawson creterion. The author offers an innovation. ICF has on the inside surface of the shell-shaped combustion chamber a covering of small Prism Reflectors (PR) and plasma reflector. These prism reflectors have a noteworthy advantage, in comparison with conventional mirror and especially with conventional shell: they multi-reflect the heat and laser radiation exactly back into collision with the fuel target capsule (pellet). The plasma reflector reflects the Bremsstrahlung radiation. The offered innovation decreases radiation losses, creates significant radiation pressure and increases the reaction time. The Lawson criterion increases by hundreds of times. The size, cost, and weight of a typical installation will decrease by tens of times. The author is researching the efficiency of these innovations. Keywords: Thermonuclear reactor, Multi-reflex AB-thermonuclear reactor, aerospace thermonuclear engine. This work is presented as paper AIAA-2006-7225 to Space-2006 Conference, 19-21 September, 2006, San Jose, CA, USA.

Alexander Bolonkin

2007-06-14T23:59:59.000Z

23

Recent Steps Towards a Controlled Thermonuclear Fusion Reactor with Results from the JET Tokamak Device  

E-Print Network [OSTI]

Recent Steps Towards a Controlled Thermonuclear Fusion Reactor with Results from the JET Tokamak Device

24

Radiation-Resistant WDM Optical Link for Thermonuclear Fusion Reactor Instrumentation  

E-Print Network [OSTI]

The future International Thermonuclear Experimental Reactor (ITER) is a complex installation that will require permanent monitoring and frequent maintenance operations. The high-gamma dose rates, the high neutron fluence, and other radiological hazards call for the use of remote-handled equipment

A. Fernandez Fernandez; Ez Fern; P. Borgermans; B. Brichard; P. Borgermans; A. I. Gusarov; M. Van Uffelen; P. Megret; M. Decréton; M. Blondel; A. Delchambre

2001-01-01T23:59:59.000Z

25

http://www3.nhk.or.jp/news/2003/12/27/k20031227000018.html 3 national visits related to proposed site for experimental reactor  

E-Print Network [OSTI]

Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor realize the Japanese proposed site for the international thermonuclear fusion experimental reactor (ITER international support for experimental reactor ITER of the fusion centering on proposed site in Aomori

26

Thermonuclear Fusion Research Progress and the Way to the Reactor  

SciTech Connect (OSTI)

The paper reviews the progress of fusion research and its prospects for electricity generation. It starts with a reminder of the principles of thermonuclear fusion and a brief discussion of its potential role in the future of the world energy production. The reactions allowing energy production by fusion of nuclei in stars and on earth and the conditions required to sustain them are reviewed. At the high temperatures required for fusion (hundred millions kelvins), matter is completely ionized and has reached what is called its 4th state: the plasma state. The possible means to achieve these extreme temperatures is discussed. The remainder of the paper focuses on the most promising of these approaches, magnetic confinement. The operating principles of the presently most efficient machine of this type -- the tokamak -- is described in some detail. On the road to producing energy with fusion, a number of obstacles have to be overcome. The plasma, a fluid that reacts to electromagnetic forces and carries currents and charges, is a complex medium. Fusion plasma is strongly heated and is therefore a good example of a system far from equilibrium. A wide variety of instabilities can grow in this system and lead to self-organized structures and spontaneous cycles. Turbulence is generated that degrades the confinement and hinders easy achievement of long lasting hot plasmas. Physicists have learned how to quench turbulence, thereby creating sort of insulating bottles inside the plasma itself to circumvent this problem. The recent history of fusion performance is outlined and the prospect of achieving power generation by fusion in a near future is discussed in the light of the development of the 'International Tokamak Experimental Reactor' project ITER.

Koch, Raymond [Laboratory for Plasma Physics, Royal Military Academy, Association EURATOM - Belgian State, 1000 Brussels (Belgium)

2006-06-08T23:59:59.000Z

27

Stars as thermonuclear reactors: their fuels and ashes  

E-Print Network [OSTI]

Atomic nuclei are transformed into each other in the cosmos by nuclear reactions inside stars: -- the process of nucleosynthesis. The basic concepts of determining nuclear reaction rates inside stars and how they manage to burn their fuel so slowly most of the time are discussed. Thermonuclear reactions involving protons in the hydrostatic burning of hydrogen in stars are discussed first. This is followed by triple alpha reactions in the helium burning stage and the issues of survival of carbon and oxygen in red giant stars connected with nuclear structure of oxygen and neon. Advanced stages of nuclear burning in quiescent reactions involving carbon, neon, oxygen and silicon are discussed. The role of neutron induced reactions in nucleosynthesis beyond iron is discussed briefly, as also the experimental detection of neutrinos from SN 1987A which confirmed broadly the ideas concerning gravitational collapse leading to a supernova.

A. Ray

2004-05-28T23:59:59.000Z

28

Application of variational techniques for parametric studies of steady-state controlled thermonuclear reactor blankets  

E-Print Network [OSTI]

APPLICATION OF VARIATIONAL TECHNIQUES FOR PARAMETRIC STUDIES OF STEADY-STATE CONTROLLED THERMONUCLEAR REACTOR BLANKETS A Thesis JAMES DAVID PEARCE Submitted to the Graduate College of Texas A6M University in partial fulfillment... of the requirement for the degree of MASTER OP SCIENCE May 1975 Ma)or Subject: Nuclear Engineering APPLICATION OF VARIATIONAL TECHNIQUES FOR PARAMETRIC STUDIES OF STEADY-STATE CONTROLLED THERMONUCLEAR REACTOR BLANKETS A Thesis by JAMES DAVID PEARCE Approved...

Pearce, James David

1975-01-01T23:59:59.000Z

29

INTERNATIONAL THERMONUCLEAR EXPERIMENTAL REACTOR TECHNICAL BASIS  

E-Print Network [OSTI]

Analysis (FDR)1 (the 1998 ITER design), supported by a body of scientific and technological data which both - to demonstrate the scientific and technological feasibility of fusion energy for peaceful purposes - and complied and Thermal Shields II.4 Fuel Cycle II.5 Water Cooling System II.6 Plasma Diagnostic System II.7 Heating

30

ROLE OF FUSION ENERGY FOR THE 21 CENTURY ENERGY MARKET AND DEVELOPMENT STRATEGY WITH INTERNATIONAL THERMONUCLEAR EXPERIMENTAL  

E-Print Network [OSTI]

THERMONUCLEAR EXPERIMENTAL REACTOR Rôle de l'énergie de fusion dans la production énergétique du 21 e siècle etROLE OF FUSION ENERGY FOR THE 21 CENTURY ENERGY MARKET AND DEVELOPMENT STRATEGY WITH INTERNATIONAL be improved to contribute to this issue. Fusion is an energy source of the Sun and the Star. It is a quite

31

Finite element modeling and experimental study of brittle fracture in tempered martensitic steels for thermonuclear fusion applications.  

E-Print Network [OSTI]

??In this work we have studied brittle fracture in high-chromium reduced activation tempered martensitic steels foreseen as structural materials for thermonuclear fusion reactors. Developing the… (more)

Mueller, Pablo Federico

2009-01-01T23:59:59.000Z

32

E-Print Network 3.0 - argentina 5f reactor Sample Search Results  

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

MARKET AND DEVELOPMENT STRATEGY WITH INTERNATIONAL THERMONUCLEAR EXPERIMENTAL Summary: THERMONUCLEAR EXPERIMENTAL REACTOR Rle de l'nergie de fusion dans la production...

33

E-Print Network 3.0 - advanced fission reactors Sample Search...  

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

fission reactors, which release energy by splitting atoms... ) International Thermonuclear Experimental Reactor (ITER), which will be ... Source: Fusiongnition Research...

34

E-Print Network 3.0 - aries tokamak reactor Sample Search Results  

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

Tokamak Physics Experiment Tokamak Fusion Test Reactor Doublet... International Thermonuclear Experimental Reactor Plasma Technologies Fusion Technologies Advanced...

35

Thermonuclear Fusion Energy : Assessment and Next Step Ren Pellat  

E-Print Network [OSTI]

Thermonuclear Fusion Energy : Assessment and Next Step René Pellat High Commissioner at the French 2000, Rome Abstract Fifty years of thermonuclear fusion work with no insurmountable road blocks have is well advanced through the International Thermonuclear Experimental Reactor (ITER) programme, which has

36

Astrophysical thermonuclear functions  

E-Print Network [OSTI]

Stars are gravitationally stabilized fusion reactors changing their chemical composition while transforming light atomic nuclei into heavy ones. The atomic nuclei are supposed to be in thermal equilibrium with the ambient plasma. The majority of reactions among nuclei leading to a nuclear transformation are inhibited by the necessity for the charged participants to tunnel through their mutual Coulomb barrier. As theoretical knowledge and experimental verification of nuclear cross sections increases it becomes possible to refine analytic representations for nuclear reaction rates. Over the years various approaches have been made to derive closed-form representations of thermonuclear reaction rates (Critchfield 1972, Haubold and John 1978, Haubold, Mathai and Anderson 1987). They show that the reaction rate contains the astrophysical cross section factor and its derivatives which has to be determined experimentally, and an integral part of the thermonuclear reaction rate independent from experimental results which can be treated by closed-form representation techniques in terms of generalized hypergeometric functions. In this paper mathematical/statistical techniques for deriving closed-form representations of thermonuclear functions will be summarized and numerical results for them will be given. The separation of thermonuclear functions from thermonuclear reaction rates is our preferred result. The purpose of the paper is also to compare numerical results for approximate and closed-form representations of thermonuclear functions. This paper completes the work of Haubold, Mathai, and Anderson (1987).

William J. Anderson; Hans J. Haubold; Arak Mathai Mathai

1993-08-23T23:59:59.000Z

37

Thermonuclear inverse magnetic pumping power cycle for stellarator reactor  

DOE Patents [OSTI]

The plasma column in a stellarator is compressed and expanded alternatively in minor radius. First a plasma in thermal balance is compressed adiabatically. The volume of the compressed plasma is maintained until the plasma reaches a new thermal equilibrium. The plasma is then expanded to its original volume. As a result of the way a stellarator works, the plasma pressure during compression is less than the corresponding pressure during expansion. Therefore, negative work is done on the plasma over a complete cycle. This work manifests itself as a back-voltage in the toroidal field coils. Direct electrical energy is obtained from this voltage. Alternatively, after the compression step, the plasma can be expanded at constant pressure. The cycle can be made self-sustaining by operating a system of two stellarator reactors in tandem. Part of the energy derived from the expansion phase of a first stellarator reactor is used to compress the plasma in a second stellarator reactor.

Ho, Darwin D. (Pleasanton, CA); Kulsrud, Russell M. (Princeton, NJ)

1991-01-01T23:59:59.000Z

38

EU to build experimental fusion reactor Associated Press, THE JERUSALEM POST Sep 25, 2006  

E-Print Network [OSTI]

EU to build experimental fusion reactor Associated Press, THE JERUSALEM POST Sep 25, 2006 European Union nations on Monday endorsed a pact to build an experimental fusion reactor with the aim, China, Japan, South Korea and Russia - also aim to ratify the International Thermonuclear Experimental

39

Lower hybrid current drive at densities required for thermonuclear reactors R. Cesario 1), L. Amicucci 2), M. L. Apicella 1), G. Calabr 1), A. Cardinali 1), C. Castaldo 1),  

E-Print Network [OSTI]

EXW/P7-02 Lower hybrid current drive at densities required for thermonuclear reactors R@frascati.enea.it Abstract. For the progress of the thermonuclear fusion energy research based on the tokamak concept in ITER (International Thermonuclear Experiment Reactor) at relatively high plasma densities also

Vlad, Gregorio

40

Feedback control of major disruptions in International Thermonuclear Experimental Reactor  

SciTech Connect (OSTI)

It is argued that major disruptions in ITER can be avoided by the feedback control of the causative MHD precursors. The sensors will be 2D-arrays of ECE detectors and the suppressors will be modulated ECH beams injected radially to produce non-thermal radial pressures to counter the radial dynamics of MHD modes. The appropriate amplitude and phase of this signal can stabilize the relevant MHD modes and prevent their evolution to a major disruption. For multimode MHD precursors, an optimal feedback scheme with a Kalman filter is discussed.

Sen, A. K. [Plasma Physics Laboratory, Columbia University, New York, New York 10026 (United States)

2011-08-15T23:59:59.000Z

Note: This page contains sample records for the topic "thermonuclear experimental reactor" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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to obtain the most current and comprehensive results.


41

E-Print Network 3.0 - aged reactor pressure Sample Search Results  

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

effort Summary: plan to build a 5 billion fusion reactor, called the International Thermonuclear Experimental Reactor... could be achieved in 35 years. "By the time our young...

42

E-Print Network 3.0 - advanced reactor research Sample Search...  

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to build the world's most advanced nuclear fusion reactor... ) International Thermonuclear Experimental Reactor (ITER), which will be built at Cadarache, near the...

43

E-Print Network 3.0 - advanced research reactor Sample Search...  

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to build the world's most advanced nuclear fusion reactor... ) International Thermonuclear Experimental Reactor (ITER), which will be built at Cadarache, near the...

44

E-Print Network 3.0 - advanced marine reactor Sample Search Results  

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to build the world's most advanced nuclear fusion reactor... ) International Thermonuclear Experimental Reactor (ITER), which will be built at Cadarache, near the...

45

E-Print Network 3.0 - almaty wwr-k reactor Sample Search Results  

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High Flux Isotope Reactor Center for Nanophase Materials Sciences... International Thermonuclear Experimental Reactor Center for Computational Sciences National Security 0 0 61 1...

46

E-Print Network 3.0 - austrian research reactor Sample Search...  

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to build the world's most advanced nuclear fusion reactor... ) International Thermonuclear Experimental Reactor (ITER), which will be built at Cadarache, near the...

47

E-Print Network 3.0 - anuclear research reactor Sample Search...  

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to build the world's most advanced nuclear fusion reactor... ) International Thermonuclear Experimental Reactor (ITER), which will be built at Cadarache, near the...

48

E-Print Network 3.0 - advanced hanaro reactor Sample Search Results  

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to build the world's most advanced nuclear fusion reactor... ) International Thermonuclear Experimental Reactor (ITER), which will be built at Cadarache, near the...

49

E-Print Network 3.0 - athene reactor Sample Search Results  

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which country... will host a nuclear fusion reactor for the International Thermonuclear Experimental Reactor (ITER) project... . The candidate sites for the international...

50

E-Print Network 3.0 - atomic reactors nouvelles Sample Search...  

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to build the world's most advanced nuclear fusion reactor... ) International Thermonuclear Experimental Reactor (ITER), which will be built at Cadarache, ... Source:...

51

E-Print Network 3.0 - advanced reactors transition Sample Search...  

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than 30 countries signed a deal on Tuesday to build the world's most advanced nuclear fusion reactor... ) International Thermonuclear Experimental Reactor (ITER), which will be...

52

E-Print Network 3.0 - astra research reactor Sample Search Results  

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than 30 countries signed a deal on Tuesday to build the world's most advanced nuclear fusion reactor... ) International Thermonuclear Experimental Reactor (ITER), which will be...

53

E-Print Network 3.0 - aprf reactor Sample Search Results  

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than 30 countries signed a deal on Tuesday to build the world's most advanced nuclear fusion reactor... ) International Thermonuclear Experimental Reactor (ITER), which will be...

54

E-Print Network 3.0 - advanced reactor study Sample Search Results  

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Hotel bargains... to iron out their differences over the site of the International Thermonuclear Experimental Reactor Source: Fusiongnition Research Experiment (FIRE) Collection:...

55

E-Print Network 3.0 - advanced fusion reactors Sample Search...  

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fusion plant deal 1 hour, 28 minutes ago Representatives of more... ) International Thermonuclear Experimental Reactor (ITER), which will be built at ... Source: Fusiongnition...

56

E-Print Network 3.0 - atomic reactors chaines Sample Search Results  

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to join round-the-world computer network ring. 28.01.2004, 21.08 Summary: thermonuclear experimental reactor (ITER) project have an opportunity to offer technical...

57

E-Print Network 3.0 - australian moata reactor Sample Search...  

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was expected on breaking... the deadlock over where to base the International Thermonuclear Experimental Reactor (ITER), the officials... for 20 years. The six parties failed...

58

E-Print Network 3.0 - auxiliary reactor area-1 Sample Search...  

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plans eyed for fusion project site Summary: said. The six parties involved in the Thermonuclear Experimental Reactor (ITER) project have been... unable to agree where to locate...

59

E-Print Network 3.0 - advanced converter reactors Sample Search...  

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computer network ring for advance science and education cooperation in Beijing... thermonuclear experimental reactor (ITER) project have an opportunity to offer technical...

60

E-Print Network 3.0 - austrian triga-mk-2 reactor Sample Search...  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

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61

E-Print Network 3.0 - ai-l-77 reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

62

E-Print Network 3.0 - agesta-r3 reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

63

E-Print Network 3.0 - atucha-1 reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

64

E-Print Network 3.0 - asco-2 reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

65

E-Print Network 3.0 - alrr reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

66

E-Print Network 3.0 - atlantic-1 reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

67

E-Print Network 3.0 - akw1 rheinsberg reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

68

E-Print Network 3.0 - ast-1 reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

69

E-Print Network 3.0 - ao-phai-1 reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

70

E-Print Network 3.0 - aguirre-1 reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

71

E-Print Network 3.0 - are-rr-1 reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

72

E-Print Network 3.0 - aguirre reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

73

E-Print Network 3.0 - arsi reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

74

E-Print Network 3.0 - afrri reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

75

E-Print Network 3.0 - arkansas-2 reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

76

E-Print Network 3.0 - arkansas-1 reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

77

E-Print Network 3.0 - argonaut reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

78

E-Print Network 3.0 - atucha-2 reactor Sample Search Results  

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

proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

79

E-Print Network 3.0 - ahfr reactor Sample Search Results  

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

proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

80

E-Print Network 3.0 - anna reactor Sample Search Results  

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

proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

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While these samples are representative of the content of NLEBeta,
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81

E-Print Network 3.0 - asco-1 reactor Sample Search Results  

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

proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

82

E-Print Network 3.0 - ardennes reactor Sample Search Results  

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

proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

83

E-Print Network 3.0 - aeg-pr-10 reactor Sample Search Results  

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

proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

84

E-Print Network 3.0 - ancon space-independent reactor Sample...  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

85

E-Print Network 3.0 - affri reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

86

E-Print Network 3.0 - aipfr reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

87

E-Print Network 3.0 - apsara reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

88

E-Print Network 3.0 - aps reactor Sample Search Results  

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

-- The United States plans to jump back into a long... States plan to build a 5 billion fusion reactor, called the International Thermonuclear Experimental Source: Fusiongnition...

89

E-Print Network 3.0 - aries-rs fusion reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor... realize the Japanese proposed site for the...

90

E-Print Network 3.0 - afsr reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

91

E-Print Network 3.0 - airos-2a space-independent reactor Sample...  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

92

E-Print Network 3.0 - aquilon reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

93

E-Print Network 3.0 - akr-1 reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

94

E-Print Network 3.0 - arbi reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

95

E-Print Network 3.0 - adsorbent-membrane reactor hamr Sample...  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

96

E-Print Network 3.0 - aarr reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

97

E-Print Network 3.0 - argonauta rien-1 reactor Sample Search...  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

98

E-Print Network 3.0 - agata reactor Sample Search Results  

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proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

99

E-Print Network 3.0 - arbus reactor Sample Search Results  

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

proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

100

E-Print Network 3.0 - atlantic-2 reactor Sample Search Results  

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

proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

Note: This page contains sample records for the topic "thermonuclear experimental 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.
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to obtain the most current and comprehensive results.


101

Astrophysical thermonuclear functions  

E-Print Network [OSTI]

As theoretical knowledge and experimental verification of nuclear cross sections increases it becomes possible to refine analytic representations for nuclear reaction rates. In this paper mathematical/statistical techniques for deriving closed-form representations of thermonuclear functions are summarized and numerical results for them are given.The purpose of the paper is also to compare numerical results for approximate and closed-form representations of thermonuclear functions.

W. J. Anderson; H. J. Haubold; A. M. Mathai

1994-02-08T23:59:59.000Z

102

E-Print Network 3.0 - alma-ata wwr-k reactor Sample Search Results  

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

proposed site in Aomori... Minister communication meeting on Japanese Proposed site for Thermonuclear fusion experimental reactor Source: Fusiongnition Research Experiment (FIRE)...

103

Concept of a thermonuclear reactor based on gravity retention of high-temperature plasma  

E-Print Network [OSTI]

In the present paper the realization of the obtained results in relation to the dense high- temperature plasma of multivalent ions including experimental data interpretation is discussed.

S. I. Fisenko; I. S. Fisenko

2007-05-27T23:59:59.000Z

104

Radiation Hardness of Passive Fibre Optic Components for the Future Thermonuclear Fusion Reactor  

E-Print Network [OSTI]

thermon uclearfusion reactor ITER will require remote-hanA#0 equipmen t to monNNfl its operation an to allow hazard-freemand-freexAN durin itsfrequen tmain ten3# periods. Heavy shielded umbilicals will be required tocon5N3 thesen2A5 an the actuators with theirinrx0flNj tation Multiplexin sen#0 signfl3 turn out to beessen tial to ease the umbilicalmancalx5 t. We arecon33NxF0# fibre optic technxfljN , with its in trinfl# wavelenflfl multiplexin (WDM) capabilities, tohanA5 these ITER multiplexin issues. We propose anA anAN2 data lin design for low-banjxF0N sennj an actuators basedon commercialo #-the-shelf (COTS) fiber optic compon5 ts. We relyon passive compon0 ts such as WDM couplersan fibre Bragggratin2 (FBG) to build a radiationfl0#NxnN t an5#j datalin0 WDM couplers remain operationx up to a 13 MGy gamma total dose. Aradiation53AxnA chan#/ drift is observed. The refractive inflNN han3 un33 ion33jj radiation is proposed as the degradation mechan30j FBG filters con tin ue to operate satisfactorily up to a 150 MGy total gamma dosean an505/3 fluen2 of about 10 15nx0 2 . Our resultson these COTS all-fibre passive compon5 ts open perspectives to build a radiation#A2/xn t an/5/ optical data lin compatible with the ITERrequiremen ts.

A. Fernandez Fernandez F. Berghmans; A. Fern; Ez Fern; M. Decréton; P. Mégret; M. Blondel; A. Delchambre; Ez A; F. Berghmans A; B. Brichard; M. Van Uffelen

2001-01-01T23:59:59.000Z

105

China To Build Its Own Fusion Reactor ENERGY TECH  

E-Print Network [OSTI]

Thermonuclear Experimental Reactor project reached agreement in Moscow Tuesday to construct the first fusion devices in thermonuclear reaction," and that "Chinese scientists started to develop a fusion operationChina To Build Its Own Fusion Reactor ENERGY TECH by Edward Lanfranco Beijing (UPI) July 1, 2005

106

Method and system to directly produce electrical power within the lithium blanket region of a magnetically confined, deuterium-tritium (DT) fueled, thermonuclear fusion reactor  

DOE Patents [OSTI]

A method for integrating liquid metal magnetohydrodynamic power generation with fusion blanket technology to produce electrical power from a thermonuclear fusion reactor located within a confining magnetic field and within a toroidal structure. A hot liquid metal flows from a liquid metal blanket region into a pump duct of an electromagnetic pump which moves the liquid metal to a mixer where a gas of predetermined pressure is mixed with the pressurized liquid metal to form a Froth mixture. Electrical power is generated by flowing the Froth mixture between electrodes in a generator duct. When the Froth mixture exits the generator the gas is separated from the liquid metal and both are recycled.

Woolley, Robert D. (Belle Mead, NJ)

1999-01-01T23:59:59.000Z

107

Thermonuclear Supernovae  

E-Print Network [OSTI]

The application of Type Ia supernovae (SNe Ia) as distance indicators in cosmology calls for a sound understanding of these objects. Recent years have seen a brisk development of astrophysical models which explain SNe Ia as thermonuclear explosions of white dwarf stars. While the evolution of the progenitor is still uncertain, the explosion mechanism certainly involves the propagation of a thermonuclear flame through the white dwarf star. Three-dimensional hydrodynamical simulations allowed to study a wide variety of possibilities involving subsonic flame propagation (deflagrations), flames accelerated by turbulence, and supersonic detonations. These possibilities lead to a variety of scenarios. I review the currently discussed approaches and present some recent results from simulations of the turbulent deflagration model and the delayed detonation model.

F. K. Roepke

2008-04-14T23:59:59.000Z

108

ASTROPHYSICAL THERMONUCLEAR FUNCTIONS  

E-Print Network [OSTI]

approaches have been made to derive closed-form representations of thermonuclear reaction rates (Critchfield

W. J. Anderson; H. J. Haubold; A. M. Mathai

1993-01-01T23:59:59.000Z

109

How far is a Fusion Power Reactor from an Experimental Reactor?  

E-Print Network [OSTI]

be able to move directly and safely to a "first of a kind" reactor. The main conditions to be satisfied / experimental evidence. To assess the reactor relevance of ITER, rather than a comparison between ITER and one1 How far is a Fusion Power Reactor from an Experimental Reactor? R. Toschi(1) , P. Barabaschi(2

110

ITER vacuum vessel fabrication plan and cost study (D 68) for the international thermonuclear experimental reactor  

SciTech Connect (OSTI)

ITER Task No. 8, Vacuum Vessel Fabrication Plan and Cost Study (D68), was initiated to assess ITER vacuum vessel fabrication, assembly, and cost. The industrial team of Raytheon Engineers & Constructors and Chicago Bridge & Iron (Raytheon/CB&I) reviewed the current vessel basis and prepared a manufacturing plan, assembly plan, and cost estimate commensurate with the present design. The guidance for the Raytheon/CB&I assessment activities was prepared by the ITER Garching Work Site. This guidance provided in the form of work descriptions, sketches, drawings, and costing guidelines for each of the presently identified vacuum vessel Work Breakdown Structure (WBS) elements was compiled in ITER Garching Joint Work Site Memo (Draft No. 9 - G 15 MD 01 94-17-05 W 1). A copy of this document is provided as Appendix 1 to this report. Additional information and clarifications required for the Raytheon/CB&I assessments were coordinated through the US Home Team (USHT) and its technical representative. Design details considered essential to the Task 8 assessments but not available from the ITER Joint Central Team (JCT) were generated by Raytheon/CB&I and documented accordingly.

NONE

1995-01-01T23:59:59.000Z

111

Experimental and Computational Study of Fluid Dynamics in Solar Reactor  

E-Print Network [OSTI]

The experimental simulation and a computational validation of a methane-cracking solar reactor powered by solar energy is the focus of this article. A solar cyclone reactor operates at over 1000 °C where the methane decomposition reaction takes...

Chien, Min-Hsiu

2014-02-19T23:59:59.000Z

112

a-1 reactor bohunice: Topics by E-print Network  

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

of degree one rather than rational points. Nguyen Le Dang Thi 7 Inexpensive Mini Thermonuclear Reactor CiteSeer Summary: This proposed design for a mini thermonuclear reactor...

113

Elastic-plastic analysis of the transition divertor joint for high performance divertor target plate  

E-Print Network [OSTI]

CER) 8. International Thermonuclear Experimental Reactor (to International Thermonuclear Experimental Reactor (International Thermonuclear Experimental Reactor (ITER) is a

Navaei, Dara

2011-01-01T23:59:59.000Z

114

Experimental measurements of the O15(alpha,gamma)Ne19 reaction rate and the stability of thermonuclear burning on accreting neutron stars  

E-Print Network [OSTI]

Neutron stars in close binary star systems often accrete matter from their companion stars. Thermonuclear ignition of the accreted material in the atmosphere of the neutron star leads to a thermonuclear explosion which is observed as an X-ray burst occurring periodically between hours and days depending on the accretion rate. The ignition conditions are characterized by a sensitive interplay between the accretion rate of the fuel supply and its depletion rate by nuclear burning in the hot CNO cycle and the rp-process. For accretion rates close to stable burning the burst ignition therefore depends critically on the hot CNO breakout reaction, O15(alpha,gamma)Ne19, that regulates the flow between the hot CNO cycle and the rapid proton capture process. Until recently, the O15(alpha,gamma)Ne19-reaction rate was not known experimentally and the theoretical estimates carried significant uncertainties. In this paper we perform a parameter study of the uncertainty of this reaction rate and determine the astrophysical consequences of the first measurement of this reaction rate. Our results corroborate earlier predictions and show that theoretically burning remains unstable up to accretion rates near the Eddington limit, in contrast to astronomical observations.

Jacob Lund Fisker; Wanpeng Tan; Joachim Goerres; Michael Wiescher; Randall L. Cooper

2007-05-07T23:59:59.000Z

115

E-Print Network 3.0 - advanced test reactor Sample Search Results  

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

20 03012006 09:51 AMLoading "People's Daily Online --Chinese experimental thermonuclear reactor on discharge test in July" Page 1 of 1http:english.people.com.cn200603...

116

Simplest AB-Thermonuclear Space Propulsion and Electric Generator  

E-Print Network [OSTI]

The author applies, develops and researches mini-sized Micro- AB Thermonuclear Reactors for space propulsion and space power systems. These small engines directly convert the high speed charged particles produced in the thermonuclear reactor into vehicle thrust or vehicle electricity with maximum efficiency. The simplest AB-thermonuclear propulsion offered allows spaceships to reach speeds of 20,000 50,000 km/s (1/6 of light speed) for fuel ratio 0.1 and produces a huge amount of useful electric energy. Offered propulsion system permits flight to any planet of our Solar system in short time and to the nearest non-Sun stars by E-being or intellectual robots during a single human life period. Key words: AB-propulsion, thermonuclear propulsion, space propulsion, thermonuclear power system.

Alexander Bolonkin

2007-01-19T23:59:59.000Z

117

Space power reactor ground test in the Experimental Gas Cooled Reactor (EGCR) at Oak Ridge  

SciTech Connect (OSTI)

The Experimental Gas Cooled Reactor (EGCR) facility and the supporting technical infrastructure at the Oak Ridge National Laboratory have the capabilities of performing ground tests of space nuclear power reactor systems. A candidate test would be a 10 MWt lithium cooled reactor, generating potassium vapor that would drive a power turbine. The facility is a large containment vessel originally intended to test the EGCR. Large, contained, and shielded spaces are available for testing, assembly, disassembly, and post-test examination.

Fontana, M.H.; Holcomb, R.S.; Cooper, R.H.

1992-08-01T23:59:59.000Z

118

June 28, 2005 France to Be Site of World's First Nuclear Fusion Reactor  

E-Print Network [OSTI]

June 28, 2005 France to Be Site of World's First Nuclear Fusion Reactor By CRAIG S. SMITH PARIS fusion reactor, an estimated $12 billion project that many scientists see as essential to solving chose the country as the site for the International Thermonuclear Experimental Reactor. Japan, which had

119

Macroscopic implications from phase space dynamics of tokamak turbulence : relaxation, transport, and flow generation  

E-Print Network [OSTI]

for the International Thermonuclear Experimental Reactor (for the International Thermonuclear Experimental Reactor (

Kosuga, Yusuke

2012-01-01T23:59:59.000Z

120

Experimental Criticality Benchmarks for SNAP 10A/2 Reactor Cores  

SciTech Connect (OSTI)

This report describes computational benchmark models for nuclear criticality derived from descriptions of the Systems for Nuclear Auxiliary Power (SNAP) Critical Assembly (SCA)-4B experimental criticality program conducted by Atomics International during the early 1960's. The selected experimental configurations consist of fueled SNAP 10A/2-type reactor cores subject to varied conditions of water immersion and reflection under experimental control to measure neutron multiplication. SNAP 10A/2-type reactor cores are compact volumes fueled and moderated with the hydride of highly enriched uranium-zirconium alloy. Specifications for the materials and geometry needed to describe a given experimental configuration for a model using MCNP5 are provided. The material and geometry specifications are adequate to permit user development of input for alternative nuclear safety codes, such as KENO. A total of 73 distinct experimental configurations are described.

Krass, A.W.

2005-12-19T23:59:59.000Z

Note: This page contains sample records for the topic "thermonuclear experimental 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

Fusion reactor control  

SciTech Connect (OSTI)

The plasma kinetic temperature and density changes, each per an injected fuel density rate increment, control the energy supplied by a thermonuclear fusion reactor in a power production cycle. This could include simultaneously coupled control objectives for plasma current, horizontal and vertical position, shape and burn control. The minimum number of measurements required, use of indirect (not plasma parameters) system measurements, and distributed control procedures for burn control are to be verifiable in a time dependent systems code. The International Thermonuclear Experimental Reactor (ITER) has the need to feedback control both the fusion output power and the driven plasma current, while avoiding damage to diverter plates. The system engineering of fusion reactors must be performed to assure their development expeditiously and effectively by considering reliability, availability, maintainability, environmental impact, health and safety, and cost.

Plummer, D.A.

1995-12-31T23:59:59.000Z

122

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

Princeton Plasma Physics Laboratory NSTX Experimental Proposal Title: Dependence of ELM size Thermonuclear Experimental Reactor (ITER) have yielded a pedestal energy loss fraction between 5% and 20 with resonant magnetic perturbations2 or by access to small ELM regimes. Fig. 1 from reference1 , where

Princeton Plasma Physics Laboratory

123

Princeton Plasma Physics Laboratory NSTX Experimental Proposal  

E-Print Network [OSTI]

Princeton Plasma Physics Laboratory NSTX Experimental Proposal Title: Dependence of ELM size Projections1 of the energy loss from Type I ELMs for the International Thermonuclear Experimental Reactor perturbations2 or by access to small ELM regimes. Fig. 1 from reference1 , where extrapolation to ITER is done

Princeton Plasma Physics Laboratory

124

Prediction of Thermonuclear Reaction Rates in Astrophysics  

E-Print Network [OSTI]

Recent improvements and remaining problems in the prediction of thermonuclear rates are reviewed. The main emphasis is on statistical model calculations, but the challenge to include direct reactions close to the driplines is also briefly addressed. Further theoretical as well as experimental investigations are motivated.

T. Rauscher

1998-10-15T23:59:59.000Z

125

Thermonuclear Ignition of Dark Galaxies  

E-Print Network [OSTI]

thermonuclear ignition of stars by nuclear fission, and the corollary, non-ignition of stars. The possibility of

J. Marvin Herndon

2006-01-01T23:59:59.000Z

126

A high-speed beam of lithium droplets for collecting diverted energy and particles in ITER (International Thermonuclear Experimental Reactor)  

SciTech Connect (OSTI)

A high-speed (160m/s) beam (0.14 {times} 0.86m) of liquid-lithium droplets passing through the divertor region(s) below (and above) the main plasma has the potential to replace and out-perform conventional'' solid divertor plates in both heat and particle removal. In addition to superior heat-collection properties, the lithium beam would: remove impurities; require low power to circulate the lithium; exhibit low-recycle divertor operation compatible with lower-hybrid current drive, H-mode plasma confinement, and no flow reversal in the edge plasma; be insensitive to plasma shifts; and finally protect solid structures from the plasma thermal energy for those disruptions that deposit energy preferentially into the divertor while simultaneously being rapidly re-established after a major disruption. Scoping calculations identifying the beam configuration and the droplet dynamics, including formation, MHD effects, gravitational effects, thermal response and hydrodynamics, are presented. Limitations and uncertainties are also discussed. 20 refs., 6 figs., 3 tabs.

Werley, K.A.

1989-01-01T23:59:59.000Z

127

Design, performance, and grounding aspects of the International Thermonuclear Experimental Reactor ion cyclotron range of frequencies antenna  

SciTech Connect (OSTI)

ITER's Ion Cyclotron Range of Frequencies (ICRF) system [Lamalle et al., Fusion Eng. Des. 88, 517–520 (2013)] comprises two antenna launchers designed by CYCLE (a consortium of European associations listed in the author affiliations above) on behalf of ITER Organisation (IO), each inserted as a Port Plug (PP) into one of ITER's Vacuum Vessel (VV) ports. Each launcher is an array of 4 toroidal by 6 poloidal RF current straps specified to couple up to 20?MW in total to the plasma in the frequency range of 40 to 55 MHz but limited to a maximum system voltage of 45?kV and limits on RF electric fields depending on their location and direction with respect to, respectively, the torus vacuum and the toroidal magnetic field. A crucial aspect of coupling ICRF power to plasmas is the knowledge of the plasma density profiles in the Scrape-Off Layer (SOL) and the location of the RF current straps with respect to the SOL. The launcher layout and details were optimized and its performance estimated for a worst case SOL provided by the IO. The paper summarizes the estimated performance obtained within the operational parameter space specified by IO. Aspects of the RF grounding of the whole antenna PP to the VV port and the effect of the voids between the PP and the Blanket Shielding Modules (BSM) surrounding the antenna front are discussed. These blanket modules, whose dimensions are of the order of the ICRF wavelengths, together with the clearance gaps between them will constitute a corrugated structure which will interact with the electromagnetic waves launched by ICRF antennas. The conditions in which the grooves constituted by the clearance gaps between the blanket modules can become resonant are studied. Simple analytical models and numerical simulations show that mushroom type structures (with larger gaps at the back than at the front) can bring down the resonance frequencies, which could lead to large voltages in the gaps between the blanket modules and perturb the RF properties of the antenna if they are in the ICRF operating range. The effect on the wave propagation along the wall structure, which is acting as a spatially periodic (toroidally and poloidally) corrugated structure, and hence constitutes a slow wave structure modifying the wall boundary condition, is examined.

Durodié, F., E-mail: frederic.durodie@rma.ac.be; Dumortier, P.; Vrancken, M.; Messiaen, A.; Huygen, S.; Louche, F.; Van Schoor, M.; Vervier, M. [LPP-ERM/KMS, Association EURATOM-Belgian State, Brussels (Belgium); Bamber, R.; Hancock, D.; Lockley, D.; Nightingale, M. P. S.; Shannon, M.; Tigwell, P.; Wilson, D. [EURATOM/CCFE Assoc., Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Maggiora, R.; Milanesio, D. [Associazione EURATOM-ENEA, Politechnico di Torino (Italy); Winkler, K. [IPP-MPI, EURATOM-Assoziation, Garching (Germany)

2014-06-15T23:59:59.000Z

128

PATHWAY PARAMETER AND THERMONUCLEAR FUNCTIONS  

E-Print Network [OSTI]

Abstract. In the theory of thermonuclear reaction rates, analytical evaluation of thermonuclear functions for non-resonant reactions, including cases with cut-off and depletion of the tail of the Maxwell-Boltzmann distribution function were considered in a series of papers by Mathai and Haubold (1988). In the present paper we study more general classes of thermonuclear functions by introducing a pathway parameter ?, so that when ? ? 1 the thermonuclear functions in the Maxwell-Boltzmannian case are recovered. We will also give interpretations for the pathway parameter ? in the case of cut-off and in terms of moments. 1. Thermonuclear Functions The standard thermonuclear function in the Maxwell-Boltzmann case in the theory of nuclear reactions, is given by the following (Critchfield, 1972; Haubold and Mathai, 1985; Mathai and

H. J. Haubold

129

akm reactor: Topics by E-print Network  

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

the flux calculation and recent progresses. Jun Cao 2012-03-08 9 Inexpensive Mini Thermonuclear Reactor CiteSeer Summary: This proposed design for a mini thermonuclear reactor...

130

akm muehleberg reactor: Topics by E-print Network  

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

the flux calculation and recent progresses. Jun Cao 2012-03-08 9 Inexpensive Mini Thermonuclear Reactor CiteSeer Summary: This proposed design for a mini thermonuclear reactor...

131

almaraz-2 reactor: Topics by E-print Network  

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

the flux calculation and recent progresses. Jun Cao 2012-03-08 5 Inexpensive Mini Thermonuclear Reactor CiteSeer Summary: This proposed design for a mini thermonuclear reactor...

132

almaraz-1 reactor: Topics by E-print Network  

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

the flux calculation and recent progresses. Jun Cao 2012-03-08 5 Inexpensive Mini Thermonuclear Reactor CiteSeer Summary: This proposed design for a mini thermonuclear reactor...

133

Ceramic breeder blanket development for fusion experimental reactor in JAERI  

SciTech Connect (OSTI)

Ceramic breeding blanket is a promising breeding blanket concept for the fusion experimental reactor, and world-wide efforts have been devoted to the design and R&D. Irradiation damages of both of breeding materials and neutron multipliers are one of the critical issues for this type of blanket, and usage of these materials as a form of small pebbles has been proposed so as to accommodate expected irradiation damages without degradation of breeding capability. The present paper outlines the progress of the design of layered pebble bed breeding blanket and also shows preliminary results of concept development related to higher fusion power accommodation and convertible blanket.

Kurasawa, T.; Takatsu, H.; Sato, S. [JAERI, Ibaraki-ken (Japan)] [and others

1994-12-31T23:59:59.000Z

134

Experimental Breeder Reactor-II Primary Tank System Wash Water Workshop  

Broader source: Energy.gov [DOE]

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

135

Simulation-Based Design and Experimental Evaluation of a Spatially Controllable CVD Reactor  

E-Print Network [OSTI]

Simulation-Based Design and Experimental Evaluation of a Spatially Controllable CVD Reactor Jae CVD reactor system has been developed that can explicitly control the spatial profile of gas, opening the door to a new class of flexible and highly controllable CVD reactor designs. © 2005 American

Rubloff, Gary W.

136

Programmable AC power supply for simulating power transient expected in fusion reactor  

SciTech Connect (OSTI)

This paper focus on control engineering of the programmable AC power source which has capability to simulate power transient expected in fusion reactor. To generate the programmable power source, AC-AC power electronics converter is adopted to control the power of a set of heaters to represent the transient phenomena of heat exchangers or heat sources of a fusion reactor. The International Thermonuclear Experimental Reactor (ITER) plasma operation scenario is used as the basic reference for producing this transient power source. (authors)

Halimi, B. [Seoul National Univ., Seoul 151-744 (Korea, Republic of); Suh, K. Y. [Seoul National Univ., Seoul 151-744 (Korea, Republic of); PHILOSOPHIA, 1 Gwanak Ro, Gwanak Gu, Seoul 151-744 (Korea, Republic of)

2012-07-01T23:59:59.000Z

137

Electron Screening Effect on Stellar Thermonuclear Fusion  

E-Print Network [OSTI]

thermonuclear fusions and show that these scenarios do not apply to stellar conditions. c ? 2013 WILEY

K. -h. Spatschek; M. Bonitz; T. Klinger; U. Ebert; C. Franck; A. V. Keudell; D. Naujoks; M. Dewitz; A. Y. Potekhin; G. Chabrier

2012-01-01T23:59:59.000Z

138

Implications of Thermonuclear-Fusion Energy Systems  

E-Print Network [OSTI]

militarytechnical reasons and implications of the very probable siting of ITER (the International Thermonuclear

André Gsponer; Jean-pierre Hurni

2004-01-01T23:59:59.000Z

139

Removal of volatile organic compounds from polluted air in a reverse flow reactor: An experimental study  

SciTech Connect (OSTI)

An experimental study of the reverse flow reactor for the purification of contaminated air has been carried out. An experimental reactor with an inner diameter of 0.145 m has been constructed. It almost completely reached the goal of an adiabatically operating system. The influence of several operating parameters such as gas velocity, cycle period, chemical character, and concentration of the pollutants and reactor pressure are discussed. The reactor could be operated autothermally provided that the inlet concentrations were sufficiently high. If a mixture of contaminants is fed to the reactor, it might be necessary to increase the total hydrocarbon concentration to assure an autothermal process. Increasing the reactor pressure will hardly change the axial temperature profiles, if the mass flux is kept constant. Increasing the mass flow rate will lead to a higher plateau temperature. Not only the reactor behavior at fixed operating conditions, but also the response of the reactor toward variations in inlet conditions is reported.

Beld, B. van de; Borman, R.A.; Derkx, O.R.; Woezik, B.A.A. van; Westerterp, K.R. (Univ. of Twente, Enschede (Netherlands). Dept. of Chemical Engineering)

1994-12-01T23:59:59.000Z

140

Decommissioning of Experimental Breeder Reactor - II Complex, Post Sodium Draining  

SciTech Connect (OSTI)

The Experimental Breeder Reactor - II (EBR-II) was shutdown in September 1994 as mandated by the United States Department of Energy. This sodium-cooled reactor had been in service since 1964. The bulk sodium was drained from the primary and secondary systems and processed. Residual sodium remaining in the systems after draining was converted into sodium bicarbonate using humid carbon dioxide. This technique was tested at Argonne National Laboratory in Illinois under controlled conditions, then demonstrated on a larger scale by treating residual sodium within the EBR-II secondary cooling system, followed by the primary tank. This process, terminated in 2002, was used to place a layer of sodium bicarbonate over all exposed surfaces of sodium. Treatment of the remaining EBR-II sodium is governed by the Resource Conservation and Recovery Act (RCRA). The Idaho Department of Environmental Quality issued a RCRA Operating Permit in 2002, mandating that all hazardous materials be removed from EBR-II within a 10 year period, with the ability to extend the permit and treatment period for another 10 years. A preliminary plan has been formulated to remove the remaining sodium and NaK from the primary and secondary systems using moist carbon dioxide, steam and nitrogen, and a water flush. The moist carbon dioxide treatment was resumed in May 2004. As of August 2005, approximately 60% of the residual sodium within the EBR-II primary tank had been treated. This process will continue through the end of 2005, when it is forecast that the process will become increasingly ineffective. At that time, subsequent treatment processes will be planned and initiated. It should be noted that the processes and anticipated costs associated with these processes are preliminary. Detailed engineering has not been performed, and approval for these methods has not been obtained from the regulator or the sponsors.

J. A. (Bart) Michelbacher; S. Paul Henslee; Collin J. Knight; Steven R. sherman

2005-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermonuclear experimental 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

COMPUTATIONAL AND EXPERIMENTAL MODELING OF SLURRY BUBBLE COLUMN REACTORS  

SciTech Connect (OSTI)

This project is a collaborative effort between the University of Akron, Illinois Institute of Technology and two industries: UOP and Energy International. The tasks involve the development of transient two and three dimensional computer codes for slurry bubble column reactors, optimization, comparison to data, and measurement of input parameters, such as the viscosity and restitution coefficients. To understand turbulence, measurements were done in the riser with 530 micron glass beads using a PIV technique. This report summarizes the measurements and simulations completed as described in details in the attached paper, ''Computational and Experimental Modeling of Three-Phase Slurry-Bubble Column Reactor.'' The Particle Image Velocimetry method described elsewhere (Gidaspow and Huilin, 1996) was used to measure the axial and tangential velocities of the particles. This method was modified with the use of a rotating colored transparent disk. The velocity distributions obtained with this method shows that the distribution is close to Maxwellian. From the velocity measurements the normal and the shear stresses were computed. Also with the use of the CCD camera a technique was developed to measure the solids volume fraction. The granular temperature profile follows the solids volume fraction profile. As predicted by theory, the granular temperature is highest at the center of the tube. The normal stress in the direction of the flow is approximately 10 times larger than that in the tangential direction. The <{nu}{prime}{sub z}{nu}{prime}{sub z}> is lower at the center where the <{nu}{prime}{sub {theta}}{nu}{prime}{sub {theta}}> is higher at that point. The Reynolds shear stress was small, producing a restitution coefficient near unity. The normal Reynolds stress in the direction of flow is large due to the fact that it is produced by the large gradient of velocity in the direction of flow compared to the small gradient in the {theta} and r directions. The kinetic theory gives values of viscosity that agree with our previous measurements (Gidaspow, Wu and Mostofi, 1999). The values of viscosity obtained from pressure drop minus weight of bed measurements agree at the center of the tube.

Paul Lam; Dimitri Gidaspow

2001-08-01T23:59:59.000Z

142

Measurement of neutron capture on $^{48}$Ca at thermal and thermonuclear energies  

E-Print Network [OSTI]

At the Karlsruhe pulsed 3.75\\,MV Van de Graaff accelerator the thermonuclear $^{48}$Ca(n,$\\gamma$)$^{49}$Ca(8.72\\,min) cross section was measured by the fast cyclic activation technique via the 3084.5\\,keV $\\gamma$-ray line of the $^{49}$Ca-decay. Samples of CaCO$_3$ enriched in $^{48}$Ca by 77.87\\,\\% were irradiated between two gold foils which served as capture standards. The capture cross-section was measured at the neutron energies 25, 151, 176, and 218\\,keV, respectively. Additionally, the thermal capture cross-section was measured at the reactor BR1 in Mol, Belgium, via the prompt and decay $\\gamma$-ray lines using the same target material. The $^{48}$Ca(n,$\\gamma$)$^{49}$Ca cross-section in the thermonuclear and thermal energy range has been calculated using the direct-capture model combined with folding potentials. The potential strengths are adjusted to the scattering length and the binding energies of the final states in $^{49}$Ca. The small coherent elastic cross section of $^{48}$Ca+n is explained through the nuclear Ramsauer effect. Spectroscopic factors of $^{49}$Ca have been extracted from the thermal capture cross-section with better accuracy than from a recent (d,p) experiment. Within the uncertainties both results are in agreement. The non-resonant thermal and thermonuclear experimental data for this reaction can be reproduced using the direct-capture model. A possible interference with a resonant contribution is discussed. The neutron spectroscopic factors of $^{49}$Ca determined from shell-model calculations are compared with the values extracted from the experimental cross sections for $^{48}$Ca(d,p)$^{49}$Ca and $^{48}$Ca(n,$\\gamma$)$^{49}$Ca.

H. Beer; C. Coceva; P. V. Sedyshev; Yu. P. Popov; H. Herndl; R. Hofinger; P. Mohr; H. Oberhummer

1996-08-07T23:59:59.000Z

143

President Truman Orders Development of Thermonuclear Weapon ...  

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

Orders Development of Thermonuclear Weapon | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing...

144

Approaches to modeling thermonuclear flames  

E-Print Network [OSTI]

Turbulence-flame interactions of thermonuclear fusion flames occurring in Type Ia Supernovae were studied by means of incompressible DNS with a highly simplified flame description. The flame is treated as a single diffusive scalar field with a nonlinear source term. It is characterized by its

J. C. Niemeyer; W. K. Bushe; G. R. Ruetsch

145

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

SciTech Connect (OSTI)

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

146

Thermonuclear Ignition of Dark Galaxies  

E-Print Network [OSTI]

Dark matter is thought to be at least an order of magnitude more abundant than luminous matter in the Universe, but there has yet to be an unambiguous identification of a wholly dark, galactic-scale structure. There is, however, increasing evidence that VIRGOHI 21 may be a dark galaxy. If VIRGOHI 21 turns out to be composed of dark stars, having approximately the mass of stars found in luminous galaxies, it will pose an enigma within the framework of current astrophysical models, but will provide strong support for my concept, published in 1994 in the Proceedings of the Royal Society of London, of the thermonuclear ignition of stars by nuclear fission, and the corollary, non-ignition of stars. The possibility of galactic thermonuclear ignition is discussed from that framework and leads to my suggestion that the distribution of luminous stars in a galaxy may simply be a reflection of the galactic distribution of the heavy elements.

J. Marvin Herndon

2006-01-01T23:59:59.000Z

147

New Views of Thermonuclear Bursts  

E-Print Network [OSTI]

Since the advent of powerful new X-ray observatories, NASA's Rossi X-ray Timing Explorer (RXTE), the Italian - Dutch BeppoSAX mission, XMM-Newton and Chandra, a number of entirely new phenomena associated with thermonuclear burning on neutron stars have been discovered. These include: (i) the discovery of millisecond (300 - 600 Hz) oscillations during bursts, so called ``burst oscillations'', (ii) a new regime of nuclear burning on neutron stars which manifests itself through the generation of hours long flares about once a decade, now referred to as ``superbursts'',(iii) discoveries of bursts from low accretion rate neutron stars, and (iv) new evidence for discrete spectral features from bursting neutron stars. In this article we review our current understanding of thermonuclear bursts on neutron stars, with a focus on these new phenomena.

Tod Strohmayer; Lars Bildsten

2003-05-06T23:59:59.000Z

148

Thermonuclear Ignition of Dark Galaxies  

E-Print Network [OSTI]

Dark matter is thought to be at least an order of magnitude more abundant than luminous matter in the Universe, but there has yet to be an unambiguous identification of a wholly dark, galactic-scale structure. There is, however, increasing evidence that VIRGOHI 21 may be a dark galaxy. If VIRGOHI 21 turns out to be composed of dark stars, having approximately the same mass of stars found in luminous galaxies, it will pose an enigma within the framework of current astrophysical models, but will provide strong support for my concept, published in 1994 in the Proceedings of the Royal Society of London, of the thermonuclear ignition of stars by nuclear fission, and the corollary, non-ignition of stars. The possibility of galactic thermonuclear ignition is discussed from that framework and leads to my suggestion that the distribution of luminous stars in a galaxy may simply be a reflection of the galactic distribution of the heavy elements.

J. Marvin Herndon

2006-04-13T23:59:59.000Z

149

Experimental Highlights - 2014  

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

weapons as they age or are subjected to the immense pressures and temperatures of a thermonuclear explosion. By providing experimental data to compare to computer models of...

150

4/20/14 12:35 PMSenators Request GAO Investigation of Costs at Experimental Fusion React...tems -Newsroom -U.S. Senate Committee on Energy and Natural Resources Page 1 of 2http://www.energy.senate.gov/public/index.cfm/featured-items?ID=854ad0a0-fe2a-4a04-  

E-Print Network [OSTI]

Thermonuclear Experimental Reactor and its effect on U.S. fusion programs. Senators Ron Wyden, D-Ore., Lisa4/20/14 12:35 PMSenators Request GAO Investigation of Costs at Experimental Fusion React.S. fusion energy science programs and user facilities have, and may continue to be, cut to pay

151

Approaches to modeling thermonuclear flames  

E-Print Network [OSTI]

Turbulence-flame interactions of thermonuclear fusion flames occurring in Type Ia Supernovae were studied by means of incompressible DNS with a highly simplified flame description. The flame is treated as a single diffusive scalar field with a nonlinear source term. It is characterized by its Prandtl number, Pr ? 1, and laminar flame speed, SL. We find that if SL ? u ?,whereu ? is the rms amplitude of turbulent velocity fluctuations, the local flame propagation speed does not significantly deviate from SL even in the presence of velocity fluctuations on scales below the laminar flame thickness. This result is interpreted in the context of subgrid-scale modeling of supernova explosions. 1.

J. C. Niemeyer; W. K. Bushe; G. R. Ruetsch

152

1 Thermonuclear Operation Space Lift  

E-Print Network [OSTI]

The “Project Orion ” small fission bomb propulsion concept proposed the one-stage launching of large payloads into low earth orbit, but it was abandoned because of the radioactive fallout into the earth atmosphere. The idea is here revived by the replacement of the small fission bombs with pure deuterium-tritium fusion bombs, and the pusher plate of the Project Orion with a large magnetic mirror. The ignition of the thermonuclear fusion reaction is done by the transient formation of keV super-explosives under the high pressure of a convergent shock wave launched into liquid hydrogen propellant by a conventional high explosive. 1.

F. Winterberg

153

Experimental Studies of NGNP Reactor Cavity Cooling System With Water  

SciTech Connect (OSTI)

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

Michael Corradini; Mark Anderson; Yassin Hassan; Akira Tokuhiro

2013-01-16T23:59:59.000Z

154

Workshop on Thermonuclear Reaction Rates for Astrophysics Applications  

E-Print Network [OSTI]

Workshop on Thermonuclear Reaction Rates for Astrophysics Applications 24-25 November 2011, Athensrd and final circular for the Workshop on Thermonuclear Reaction Rates for Astrophysics Applications

155

A E Costley, US/ITER Town meeting, San Diego, 22 April 2004 N 55 IP 57 04-04-30 F 1 International Thermonuclear Experimental Reactor  

E-Print Network [OSTI]

for the integration have been developed and the interfaces with the re to their anticipated operational role (machine protection, control and physics studies). About 45 parameters in total). These are included in the highest level ITER design requirement document (DRG 1). · For each parameter

156

Toward the Development of Radiation-Tolerant Instrumentation Data Links for Thermonuclear Fusion Experiments  

E-Print Network [OSTI]

Thermonuclear reactors will require permanent monitoring under high-gamma dose rates and high neutron flux. We propose to get rid of the digital data transmission limitations in highly radioactive environments by implementing an analog fiber-optic link based on directly modulated vertical

Alberto Fernandez Fernandez; Ez Fern; F. Berghmans; B. Brichard; M. Decreton

2002-01-01T23:59:59.000Z

157

CO{sub 2} adsorption: Experimental investigation with kinetics verification and CFD reactor model validation  

SciTech Connect (OSTI)

The National Energy Technology Laboratory is investigating a new process for CO{sub 2} capture from large sources such as utility power generation facilities as an alternative to liquid amine based absorption processes. Many, but not all of these advanced dry processes are based upon sorbents composed of supported polyamines. In this analysis, experiments have been conducted in a small facility at different temperatures and compared to CFD reactor predictions using kinetics obtained from TGA tests. This particular investigation compares the predicted performance and the experimental performance of one of these new class of sorbents in a fluidized bed reactor. In the experiment, the sorbent absorbs CO{sub 2} from simulated flue gas in a riser reactor, separates the carbonated particles from the de-carbonated flue gas in a cyclone and then regenerates the sorbent, creating a concentrated stream of pure CO{sub 2} for sequestration. In this work, experimental measurements of adsorption are compared to predictions from a 3-dimensional non-isothermal reacting multiphase flow model. The effects of the gas flow rate and reactor temperature are explored. It is shown that the time duration for CO{sub 2} adsorption decreased for an increase in the gas flow. The details of the experimental facility and the model as well as the comparative analysis between the data and the simulation results are discussed.

Breault, Ronald W, [U.S. DOE; Huckaby, Ernest D. [U.S. DOE; Shadle, Lawrence J [U.S. DOE; Spenik, James L. [REM Engineering PLLC

2013-01-01T23:59:59.000Z

158

Experimental study of Siphon breaker about size effect in real scale reactor design  

SciTech Connect (OSTI)

Rupture accident within the pipe of a nuclear reactor is one of the main causes of a loss of coolant accident (LOCA). Siphon-breaking is a passive method that can prevent a LOCA. In this study, either a line or a hole is used as a siphon-breaker, and the effect of various parameters, such as the siphon-breaker size, pipe rupture point, pipe rupture size, and the presence of an orifice, are investigated using an experimental facility similar in size to a full-scale reactor. (authors)

Kang, S. H. [Mechanical Engineering Dept., POSTECH, Pohang, 790-784 (Korea, Republic of); Ahn, H. S. [Div. of Advanced Nuclear Engineering, POSTECH, Pohang, 790-784 (Korea, Republic of); Kim, J. M. [Mechanical Engineering Dept., POSTECH, Pohang, 790-784 (Korea, Republic of); Joo, H. M. [Dept. of Nuclear Engineering, Hanyang Univ., Seoul, 133-791 (Korea, Republic of); Lee, K. Y.; Seo, K.; Chi, D. Y. [KAERI, Yuseong, Daejeon, 305-353 (Korea, Republic of); Kim, M. H. [Div. of Advanced Nuclear Engineering, POSTECH, Pohang, 790-784 (Korea, Republic of)

2012-07-01T23:59:59.000Z

159

Statistical Methods for Thermonuclear Reaction Rates and Nucleosynthesis Simulations  

E-Print Network [OSTI]

Rigorous statistical methods for estimating thermonuclear reaction rates and nucleosynthesis are becoming increasingly established in nuclear astrophysics. The main challenge being faced is that experimental reaction rates are highly complex quantities derived from a multitude of different measured nuclear parameters (e.g., astrophysical S-factors, resonance energies and strengths, particle and gamma-ray partial widths). We discuss the application of the Monte Carlo method to two distinct, but related, questions. First, given a set of measured nuclear parameters, how can one best estimate the resulting thermonuclear reaction rates and associated uncertainties? Second, given a set of appropriate reaction rates, how can one best estimate the abundances from nucleosynthesis (i.e., reaction network) calculations? The techniques described here provide probability density functions that can be used to derive statistically meaningful reaction rates and final abundances for any desired coverage probability. Examples ...

Iliadis, Christian; Coc, Alain; Timmes, F X; Champagne, Art E

2014-01-01T23:59:59.000Z

160

Thermonuclear burst physics with RXTE  

E-Print Network [OSTI]

Abstract. Recently we have made measurements of thermonuclear burst energetics and recurrence times which are unprecedented in their precision, largely thanks to the sensitivity of the Rossi X-ray Timing Explorer (RXTE). In the "Clocked Burster", GS 1826?24, hydrogen burns during the burst via the rapid-proton (rp) process, which has received particular attention in recent years through theoretical and modelling studies. The burst energies and the measured variation of alpha (the ratio of persistent to burst flux) with accretion rate strongly suggests solar metallicity in the neutron star atmosphere, although this is not consistent with the corresponding variation of the recurrence time. Possible explanations include extra heating between the bursts, or a change in the fraction of the neutron star over which accretion takes place. I also present results from 4U 1746?37, which exhibits regular burst trains which are interrupted by “out of phase ” bursts.

Duncan K. Galloway; Deepto Chakrabarty; Andrew Cumming; Erik Kuulkers; Lars Bildsten; Richard Rothschild

2004-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermonuclear experimental 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

Thermonuclear burst physics with RXTE  

E-Print Network [OSTI]

Recently we have made measurements of thermonuclear burst energetics and recurrence times which are unprecedented in their precision, largely thanks to the sensitivity of the Rossi X-ray Timing Explorer. In the "Clocked Burster", GS 1826-24, hydrogen burns during the burst via the rapid-proton (rp) process, which has received particular attention in recent years through theoretical and modelling studies. The burst energies and the measured variation of alpha (the ratio of persistent to burst flux) with accretion rate strongly suggests solar metallicity in the neutron star atmosphere, although this is not consistent with the corresponding variation of the recurrence time. Possible explanations include extra heating between the bursts, or a change in the fraction of the neutron star over which accretion takes place. I also present results from 4U 1746-37, which exhibits regular burst trains which are interrupted by "out of phase" bursts.

D. K. Galloway; D. Chakrabarty; A. Cumming; E. Kuulkers; L. Bildsten; R. Rothschild

2004-04-22T23:59:59.000Z

162

Tidally-induced thermonuclear Supernovae  

E-Print Network [OSTI]

We discuss the results of 3D simulations of tidal disruptions of white dwarfs by moderate-mass black holes as they may exist in the cores of globular clusters or dwarf galaxies. Our simulations follow self-consistently the hydrodynamic and nuclear evolution from the initial parabolic orbit over the disruption to the build-up of an accretion disk around the black hole. For strong enough encounters (pericentre distances smaller than about 1/3 of the tidal radius) the tidal compression is reversed by a shock and finally results in a thermonuclear explosion. These explosions are not restricted to progenitor masses close to the Chandrasekhar limit, we find exploding examples throughout the whole white dwarf mass range. There is, however, a restriction on the masses of the involved black holes: black holes more massive than 2 × 10 5 M? swallow a typical 0.6 M ? white dwarf before their tidal forces can overwhelm the star’s selfgravity. Therefore, this mechanism is characteristic for black holes of moderate masses. The material that remains bound to the black hole settles into an accretion disk and produces an X-ray flare close to the Eddington limit of LEdd ? 10 41 erg/s (Mbh/1000M?), typically lasting for a few months. The combination of a peculiar thermonuclear supernova together with an X-ray flare thus whistle-blows the existence of such moderate-mass black holes. The next generation of wide field space-based instruments should be able to detect such events. 1.

Stephan Rosswog; Enrico Ramirez-ruiz; W. Raphael Hix

163

Tidally-induced thermonuclear Supernovae  

E-Print Network [OSTI]

We discuss the results of 3D simulations of tidal disruptions of white dwarfs by moderate-mass black holes as they may exist in the cores of globular clusters or dwarf galaxies. Our simulations follow self-consistently the hydrodynamic and nuclear evolution from the initial parabolic orbit over the disruption to the build-up of an accretion disk around the black hole. For strong enough encounters (pericentre distances smaller than about 1/3 of the tidal radius) the tidal compression is reversed by a shock and finally results in a thermonuclear explosion. These explosions are not restricted to progenitor masses close to the Chandrasekhar limit, we find exploding examples throughout the whole white dwarf mass range. There is, however, a restriction on the masses of the involved black holes: black holes more massive than $2\\times 10^5$ M$_\\odot$ swallow a typical 0.6 M$_\\odot$ dwarf before their tidal forces can overwhelm the star's self-gravity. Therefore, this mechanism is characteristic for black holes of moderate masses. The material that remains bound to the black hole settles into an accretion disk and produces an X-ray flare close to the Eddington limit of $L_{\\rm Edd} \\simeq 10^{41} {\\rm erg/s} M_{\\rm bh}/1000 M$_\\odot$), typically lasting for a few months. The combination of a peculiar thermonuclear supernova together with an X-ray flare thus whistle-blows the existence of such moderate-mass black holes. The next generation of wide field space-based instruments should be able to detect such events.

S. Rosswog; E. Ramirez-Ruiz; W. R. Hix

2008-11-13T23:59:59.000Z

164

Workshop on Thermonuclear Reaction Rates for Astrophysics Applications  

E-Print Network [OSTI]

Workshop on Thermonuclear Reaction Rates for Astrophysics Applications 24-25 November 2011, Athens circular for the Workshop on Thermonuclear Reaction Rates for Astrophysics Applications, to be held of thermonuclear reaction rates. The topics of the workshop, in relation with thermonuclear reaction rates

165

The physics of antimatter induced fusion and thermonuclear explosions  

E-Print Network [OSTI]

triggering large scale thermonuclear explosions is investigated. The number of antiproton annihilations

Andre Gsponer; Jean-pierre Hurni

166

Electron screening effect on stellar thermonuclear fusion  

E-Print Network [OSTI]

We study the impact of plasma correlation effects on nonresonant thermonuclear reactions for various stellar objects, namely in the liquid envelopes of neutron stars, and the interiors of white dwarfs, low-mass stars, and substellar objects. We examine in particular the effect of electron screening on the enhancement of thermonuclear reactions in dense plasmas within and beyond the linear mixing rule approximation as well as the corrections due to quantum effects at high density. In addition, we examine some recent unconventional (Yukawa-potential and "quantum-tail") theoretical results on stellar thermonuclear fusions and show that these scenarios do not apply to stellar conditions.

Potekhin, A Y

2013-01-01T23:59:59.000Z

167

Material unaccounted for at the Southwest Experimental Fast Oxide Reactor: The SEFOR MUF  

SciTech Connect (OSTI)

The U.S. Atomic Energy Commission contracted with the General Electric Company to design, construct, and operate the Southwest Experimental Fast Oxide Reactor (SEFOR) to measure the Doppler effect for fast neutron breeder reactors. It contracted with Nuclear Fuel Services to fabricate the fuel rods for the reactor. When the reactor went critical in May, 1969, it appeared that some of the mixed uranium-plutonium oxide (MOX) fuel rods did not contain the specified quantity of plutonium. The SEFOR operators soon found several fuel rods which appeared to be low in plutonium. The safeguards group at Brookhaven was asked to look into the problem and, if possible, determine how much plutonium was missing from the unirradiated rods and from the larger number which had been slightly irradiated in the reactor. It was decided that the plutonium content of the unirradiated and irradiated rods could be measured relative to a reference rod using a high resolution gamma-ray detector and also by neutron measurements using an auto-correlation circuit recently developed at the Naval Research Laboratory (NRL). During the next two years, Brookhaven personnel and C.V. Strain of NRL made several trips to the SEFOR reactor. About 250 of the 775 rods were measured by two or more methods, using a sodium-iodide detector, a high-resolution germanium detector, a neutron detector, or the reactor (to measure reactivity). The research team concluded that 4.6 {+-} 0.46 kg of plutonium was missing out of the 433 kg that the rods should have contained. This report describes the SEFOR experiment and the procedures used to determine the material unaccounted for, or MUF.

Higinbotham, W.A.

1994-11-07T23:59:59.000Z

168

E-Print Network 3.0 - advanced passive reactor Sample Search...  

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

... Source: Fusiongnition Research Experiment (FIRE) Collection: Plasma Physics and Fusion 37 ITER --"INTERNATIONAL THERMONUCLEAR EXPERIMENTAL RESEARCH PROGRAM". Summary:...

169

UV Light Curves of Thermonuclear Supernovae  

E-Print Network [OSTI]

Ultraviolet light curves are calculated for several thermonuclear supernova models using a multifrequency radiation hydrodynamic code. It is found that Chandrasekhar-mass models produce very similar light curves both for detonation and deflagration. Sub-Chandrasekhar-mass models essentially differ from ``normal'' Chandrasekhar ones regarding behaviour of their UV fluxes. Differences in absolute brightness and in shape of light curves of thermonuclear supernovae could be detectable up to 300 Mpc with modern UV space telescopes.

S. I. Blinnikov; E. I. Sorokina

2000-03-17T23:59:59.000Z

170

An Experimental Test Facility to Support Development of the Fluoride Salt Cooled High Temperature Reactor  

SciTech Connect (OSTI)

The need for high-temperature (greater than 600 C) energy exchange and delivery systems is significantly increasing as the world strives to improve energy efficiency and develop alternatives to petroleum-based fuels. Liquid fluoride salts are one of the few energy transport fluids that have the capability of operating at high temperatures in combination with low system pressures. The Fluoride Salt-Cooled High-Temperature Reactor design uses fluoride salt to remove core heat and interface with a power conversion system. Although a significant amount of experimentation has been performed with these salts, specific aspects of this reactor concept will require experimental confirmation during the development process. The experimental facility described here has been constructed to support the development of the Fluoride Salt Cooled High Temperature Reactor concept. The facility is capable of operating at up to 700 C and incorporates a centrifugal pump to circulate FLiNaK salt through a removable test section. A unique inductive heating technique is used to apply heat to the test section, allowing heat transfer testing to be performed. An air-cooled heat exchanger removes added heat. Supporting loop infrastructure includes a pressure control system; trace heating system; and a complement of instrumentation to measure salt flow, temperatures, and pressures around the loop. The initial experiment is aimed at measuring fluoride salt heat transfer inside a heated pebble bed similar to that used for the core of the pebble bed advanced high-temperature reactor. This document describes the details of the loop design, auxiliary systems used to support the facility, the inductive heating system, and facility capabilities.

Yoder Jr, Graydon L [ORNL] [ORNL; Aaron, Adam M [ORNL] [ORNL; Cunningham, Richard Burns [University of Tennessee, Knoxville (UTK)] [University of Tennessee, Knoxville (UTK); Fugate, David L [ORNL] [ORNL; Holcomb, David Eugene [ORNL] [ORNL; Kisner, Roger A [ORNL] [ORNL; Peretz, Fred J [ORNL] [ORNL; Robb, Kevin R [ORNL] [ORNL; Wilgen, John B [ORNL] [ORNL; Wilson, Dane F [ORNL] [ORNL

2014-01-01T23:59:59.000Z

171

White dwarf mergers,White dwarf mergers, thermonuclear supernovae,thermonuclear supernovae,  

E-Print Network [OSTI]

White dwarf mergers,White dwarf mergers, thermonuclear supernovae,thermonuclear supernovae fusion is ignited. Degenerate, hence runaway. #12;CO white dwarf accretes, either from companion, or from disk after merger. As it approaches maximum mass, C fusion is ignited. Degenerate, hence runaway. SN Ia

Hinton, Jim

172

E-Print Network 3.0 - advanced reactor licensing Sample Search...  

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

in advanced fuel and materials, nuclear medicine... of fission power reactors, to thermonuclear fusion and plasma physics, ... Source: Entekhabi, Dara - Kavli Institute for...

173

E-Print Network 3.0 - aberdeen maryland reactor Sample Search...  

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

for fusion. The project is part... alternatives to current reactor designs (see sidebar). Thermonuclear fusion is the engine that powers the sun Source: Massachusetts Institute of...

174

E-Print Network 3.0 - alternative reactor vessel Sample Search...  

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

full2855429821 Summary: alternatives to current reactor designs (see sidebar). Thermonuclear fusion is the engine that powers the sun... Alerts || Subscription HELP ||...

175

E-Print Network 3.0 - advanced integral reactor Sample Search...  

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

in advanced fuel and materials, nuclear medicine... of fission power reactors, to thermonuclear fusion and plasma physics, ... Source: Entekhabi, Dara - Kavli Institute for...

176

E-Print Network 3.0 - advanced reactor instrumentation Sample...  

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

in advanced fuel and materials, nuclear medicine... of fission power reactors, to thermonuclear fusion and plasma physics, ... Source: Entekhabi, Dara - Kavli Institute for...

177

Modeling and Experimental Tests on the Hydraulically Driven Control Rod option for IRIS Reactor  

SciTech Connect (OSTI)

The adoption of Internal Control Rod Drive Mechanisms (ICRDMs) represents a valuable alternative to classical, external CRDMs based on electro-magnetic devices, as adopted in current PWRs. The advantages on the safety features of the reactor are apparent: inherent elimination of the Rod Ejection accidents and of possible concerns about the vessel head penetrations. A further positive feedback on the design is the reduction of the primary system overall dimensions. Within the frame of the ICRDM concepts, the Hydraulically Driven Control Rod solution is investigated as a possible option for the IRIS integral reactor. After a brief comparison of the solutions currently proposed for integral reactors, the configuration of the Hydraulic Control Rod device for IRIS, made up by an external movable piston and an internal fixed cylinder, is described. A description of the whole control system is reported as well. Particular attention is devoted to the Control Rod profile characterization, performed by means of a Computational Fluid Dynamics (CFD) analysis. The investigation of the system behavior has been carried out, including the dynamic equilibrium and its stability properties, the withdrawal and insertion step movement and the sensitivity study on command time periods. A suitable dynamic model has been set up for the mentioned purposes: the models corresponding to the various Control Rod system devices have been written in an Object-Oriented language (Modelica), thus allowing an easy implementation of such a system into the simulator for the whole reactor. Finally, a preliminary low pressure, low temperature, reduced length experimental facility has been built. Tests on HDCR stability and operational transients have been performed. The results are compared with the dynamic system model and CFD simulation model, showing good agreement between simulations and experimental data. During these preliminary tests, the control system performed correctly, allowing stable dynamic equilibrium positions for the Control Rod and stable behavior during withdrawal and insertion steps. (authors)

Cammi, Antonio; Ricotti, Marco E.; Vitulo, Alessia [Department of Nuclear Engineering, Politecnico di Milano, Via Ponzio, 34/3, 20133 Milano (Italy)

2004-07-01T23:59:59.000Z

178

Convective heating analysis of an IFE target in a high temperature, low Reynolds number xenon environment  

E-Print Network [OSTI]

conditions required for thermonuclear burn lies on the edgeThe International Thermonuclear Experimental Reactor (ITER)is successful in achieving thermonuclear burn. While NIF is

Holdener, Dain Steffen

2011-01-01T23:59:59.000Z

179

Experimental Evaluation of the Thermal Performance of a Water Shield for a Surface Power Reactor  

SciTech Connect (OSTI)

Water based reactor shielding is being investigated for use on initial lunar surface power systems. A water shield may lower overall cost (as compared to development cost for other materials) and simplify operations in the setup and handling. The thermal hydraulic performance of the shield is of significant interest. The mechanism for transferring heat through the shield is natural convection. Natural convection in a 100 kWt lunar surface reactor shield design is evaluated with 2 kW power input to the water in the Water Shield Testbed (WST) at the NASA Marshall Space Flight Center. The experimental data from the WST is used to validate a CFD model. Performance of the water shield on the lunar surface is then predicted with a CFD model anchored to test data. The experiment had a maximum water temperature of 75 deg. C. The CFD model with 1/6-g predicts a maximum water temperature of 88 deg. C with the same heat load and external boundary conditions. This difference in maximum temperature does not greatly affect the structural design of the shield, and demonstrates that it may be possible to use water for a lunar reactor shield.

Pearson, J. Boise; Stewart, Eric T. [NASA Marshall Space Flight Center, Huntsville, AL 35812 (United States); Reid, Robert S. [Los Alamos National Laboratory, Los Alamos, NM 87544 (United States)

2007-01-30T23:59:59.000Z

180

Antimatter induced fusion and thermonuclear explosions  

E-Print Network [OSTI]

The feasibility of using antihydrogen for igniting inertial confinement fusion pellets or triggering large scale thermonuclear explosions is investigated. The number of antiproton annihilations required to start a thermonuclear burn wave in either DT or Li_2DT is found to be about 10^{21}/k^2, where k is the compression factor of the fuel to be ignited. In the second part, the technologies for producing antiprotons with high energy accelerator systems and the means for manipulating and storing microgram amounts of antihydrogen are examined. While there seems to be no theoretical obstacles to the production of 10^{18} antiprotons per day (the amount required for triggering one thermonuclear bomb), the construction of such a plant involves several techniques which are between 3 and 4 orders of magnitude away from present day technology.

Gsponer, A; Gsponer, Andre; Hurni, Jean-Pierre

1987-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermonuclear experimental 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

E-Print Network 3.0 - ab-thermonuclear space propulsion Sample...  

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

thermonuclear space propulsion Search Powered by Explorit Topic List Advanced Search Sample search results for: ab-thermonuclear...

182

Modeling and Experimental Studies of Mercury Oxidation and Adsorption in a Fixed-Bed Reactor  

SciTech Connect (OSTI)

This report presents experimental and modeling mercury oxidation and adsorption data. Fixed-bed and single-particle models of mercury adsorption were developed. The experimental data were obtained with two reactors: a 300- W, methane-fired, tubular, quartz-lined reactor for studying homogeneous oxidation reactions and a fixed-bed reactor, also of quartz, for studying heterogeneous reactions. The latter was attached to the exit of the former to provide realistic combustion gases. The fixed-bed reactor contained one gram of coconut-shell carbon and remained at a temperature of 150oC. All methane, air, SO2, and halogen species were introduced through the burner to produce a radical pool representative of real combustion systems. A Tekran 2537A Analyzer coupled with a wet conditioning system provided speciated mercury concentrations. At 150°C and in the absence of HCl or HBr, the mercury uptake was about 20%. The addition of 50 ppm HCl caused complete capture of all elemental and oxidized mercury species. In the absence of halogens, SO2 increased the mercury adsorption efficiency to up to 30 percent. The extent of adsorption decreased with increasing SO2 concentration when halogens were present. Increasing the HCl concentration to 100 ppm lessened the effect of SO2. The fixed-bed model incorporates Langmuir adsorption kinetics and was developed to predict adsorption of elemental mercury and the effect of multiple flue gas components. This model neglects intraparticle diffusional resistances and is only applicable to pulverized carbon sorbents. It roughly describes experimental data from the literature. The current version includes the ability to account for competitive adsorption between mercury, SO2, and NO2. The single particle model simulates in-flight sorbent capture of elemental mercury. This model was developed to include Langmuir and Freundlich isotherms, rate equations, sorbent feed rate, and intraparticle diffusion. The Freundlich isotherm more accurately described in-flight mercury capture. Using these parameters, very little intraparticle diffusion was evident. Consistent with other data, smaller particles resulted in higher mercury uptake due to available surface area. Therefore, it is important to capture the particle size distribution in the model. At typical full-scale sorbent feed rates, the calculations underpredicted adsorption, suggesting that wall effects can account for as much as 50 percent of the removal, making it an important factor in entrained-mercury adsorption models.

Paula A. Buitrago, Mike Morrill, JoAnn S. Lighty, Geoffrey D.; Silcox,

2009-06-15T23:59:59.000Z

183

THE POSSIBILITY OF PRODUCING THERMONUCLEAR REACTIONS IN A GASEOUS DISCHARGE*  

E-Print Network [OSTI]

THE POSSIBILITY OF PRODUCING THERMONUCLEAR REACTIONS IN A GASEOUS DISCHARGE* I.V. Kurchatov of the energy of thermonuclear reactions. Physicists the world over are attracted by the extraordinarily interest- ing and very difficult task of controlling thermonuclear reactiom. Investigations in this field

184

3 New Views of Thermonuclear Bursts  

E-Print Network [OSTI]

Many accreting neutron stars erupt in spectacular thermonuclear conflagrations every few hours to days. These events, known as Type I X-ray bursts, or simply X-ray bursts, are the subject of our review. Since the last review of X-ray burst phenomenology was written (Lewin, van Paradijs & Taam 1993; hereafter

Tod Strohmayer; Lars Bildsten

2003-01-01T23:59:59.000Z

185

Resonances and the thermonuclear reaction rate  

E-Print Network [OSTI]

We present an approximate analytic expression for thermonuclear reaction rate of charged particles when the cross section contains a single narrow or wide resonance described by a Breit-Wigner shape. The resulting expression is uniformly valid as the effective energy and resonance energy coalesce. We use our expressions to calculate the reaction rate for $^{12}$C(p,$\\gamma$)$^{13}$N.

M. S. Hussein; M. Ueda; A. J. Sargeant; M. P. Pato

2003-07-21T23:59:59.000Z

186

Introduction to Magnetic Thermonuclear Fusion and  

E-Print Network [OSTI]

Introduction to Magnetic Thermonuclear Fusion and Related Research Projects Ghassan Antar Fusion 2. Research on Turbulence (Theory and Experiment) 3. Research on Disruptions 4. Research on Plasma Facing Components #12;Ghassan Y. ANTAR 3 Fusion Occurs when Two Nuclei Unite to Form One The Energy

Shihadeh, Alan

187

IAEA-CN-SO/F-I-4 ITER: CONCEPT DEFINITION*  

E-Print Network [OSTI]

way. 1. INTRODUCTION The activity of the International Thermonuclear Experimental Reactor (ITER. * The activity of the International Thermonuclear Experimental Reactor (ITER) is conducted under the auspices

188

DEPARTMENT OF ENERGY Since 2001, the Administration  

E-Print Network [OSTI]

Gen, the Carbon Sequestration Leadership Forum, and the International Thermonuclear Experimental Reactor fusion to the International Thermonuclear Experimental Reactor fusion energy project. Accelerating Breakthroughs

189

October 10th Daejeon Convention Center, KOREA  

E-Print Network [OSTI]

using pilot devices during the construction phase of International Thermonuclear Experimental Reactor Thermonuclear Experimental Reactor European Union Russia China Japan United States of America India Korea #12

190

Senate Appropriations Committee Report FY04 Energy and Water Development Act  

E-Print Network [OSTI]

as a viable energy source. International Thermonuclear Experimental Reactor - The Committee recommendation negotiations aimed at building the International Thermonuclear Experimental Reactor (ITER), a burning plasma

191

Calculational-experimental research models for a fast reactor with a heterogeneous core  

SciTech Connect (OSTI)

The physical characteristics of heterogeneous metallic oxide cores were experimentally studied by physical tests of the critical assemblies BFS-46 and BFS-46AZ, which simulate a reactor of the BN-1600 type, into the core of which a fuel assembly with metallic uranium is inserted. A calculational model for the critical assemblies being investigated, showing the zones and their dimensions, is presented. The critical assembly BFS-46AZ is a modification of the basic critical assembly BFS-46 which adds plutonium to the IBZ to simulate its accumulation during reactor operation. The BFS-46 and BFS-46AZ assemblies have identical dimensions for the IBZ and LEZ, and have different HEZ dimensions, necessary to ensure the criticality of each assembly. Plutonium with a /sup 240/Pu content equal to 3.8% is used in the LEZ. The critically parameters are calculated using one-dimensional and two-dimensional models in a 26-group diffusion approximation based on the BNAP-78 system of group constants.

Belov, S.P.; Bobrov, S.B.; Kazanskii, Yu.A.; Kuzin, E.N.; Matveev, V.I.; Novozhilov, A.I.; Chernyi, V.A.

1987-11-01T23:59:59.000Z

192

Formulation and experimental evaluation of closed-form control laws for the rapid maneuvering of reactor neutronic power  

SciTech Connect (OSTI)

This report describes both the theoretical development and the experimental evaluation of a novel, robust methodology for the time-optimal adjustment of a reactor's neutronic power under conditions of closed-loop digital control. Central to the approach are the MIT-SNL Period-Generated Minimum Time Control Laws' which determine the rate at which reactivity should be changed in order to cause a reactor's neutronic power to conform to a specified trajectory. Using these laws, reactor power can be safely raised by five to seven orders of magnitude in a few seconds. The MIT-SNL laws were developed to facilitate rapid increases of neutronic power on spacecraft reactors operating in an SDI environment. However, these laws are generic and have other applications including the rapid recovery of research and test reactors subsequent to an unanticipated shutdown, power increases following the achievement of criticality on commercial reactors, power adjustments on commercial reactors so as to minimize thermal stress, and automated startups. The work reported here was performed by the Massachusetts Institute of Technology under contract to the Sandia National Laboratories. Support was also provided by the US Department of Energy's Division of University and Industry Programs. The work described in this report is significant in that a novel solution to the problem of time-optimal control of neutronic power was identified, in that a rigorous description of a reactor's dynamics was derived in that the rate of change of reactivity was recognized as the proper control signal, and in that extensive experimental trials were conducted of these newly developed concepts on actual nuclear reactors. 43 refs., 118 figs., 11 tabs.

Bernard, J.A. (Massachusetts Inst. of Tech., Cambridge, MA (USA). Nuclear Reactor Lab.)

1989-09-01T23:59:59.000Z

193

Neutron capture of 26Mg at thermonuclear energies  

E-Print Network [OSTI]

The neutron capture cross section of 26Mg was measured relative to the known gold cross section at thermonuclear energies using the fast cyclic activation technique. The experiment was performed at the 3.75 MV Van-de-Graaff accelerator, Forschungszentrum Karlsruhe. The experimental capture cross section is the sum of resonant and direct contributions. For the resonance at E(n,lab) = 220 keV our new results are in disagreement with the data from Weigmann et al. An improved Maxwellian averaged capture cross section is derived from the new experimental data taking into account s- and p-wave capture and resonant contributions. The properties of so-called potential resonances which influence the p-wave neutron capture of 26}Mg are discussed in detail.

P. Mohr; H. Beer; H. Oberhummer; G. Staudt

1998-05-20T23:59:59.000Z

194

Statistical Methods for Thermonuclear Reaction Rates and Nucleosynthesis Simulations  

E-Print Network [OSTI]

Rigorous statistical methods for estimating thermonuclear reaction rates and nucleosynthesis are becoming increasingly established in nuclear astrophysics. The main challenge being faced is that experimental reaction rates are highly complex quantities derived from a multitude of different measured nuclear parameters (e.g., astrophysical S-factors, resonance energies and strengths, particle and gamma-ray partial widths). We discuss the application of the Monte Carlo method to two distinct, but related, questions. First, given a set of measured nuclear parameters, how can one best estimate the resulting thermonuclear reaction rates and associated uncertainties? Second, given a set of appropriate reaction rates, how can one best estimate the abundances from nucleosynthesis (i.e., reaction network) calculations? The techniques described here provide probability density functions that can be used to derive statistically meaningful reaction rates and final abundances for any desired coverage probability. Examples are given for applications to s-process neutron sources, core-collapse supernovae, classical novae, and big bang nucleosynthesis.

Christian Iliadis; Richard Longland; Alain Coc; F. X. Timmes; Art E. Champagne

2014-09-19T23:59:59.000Z

195

Merging White Dwarfs and Thermonuclear Supernovae  

E-Print Network [OSTI]

Thermonuclear supernovae result when interaction with a companion reignites nuclear fusion in a carbon-oxygen white dwarf, causing a thermonuclear runaway, a catastrophic gain in pressure, and the disintegration of the whole white dwarf. It is usually thought that fusion is reignited in near-pycnonuclear conditions when the white dwarf approaches the Chandrasekhar mass. I briefly describe two long-standing problems faced by this scenario, and our suggestion that these supernovae instead result from mergers of carbon-oxygen white dwarfs, including those that produce sub-Chandrasekhar mass remnants. I then turn to possible observational tests, in particular those that test the absence or presence of electron captures during the burning.

van Kerkwijk, Marten H

2012-01-01T23:59:59.000Z

196

Argonne's rich scientific heritage Argonne's Experimental Breeder Reactor-I in Idaho lit this string of four  

E-Print Network [OSTI]

Argonne's rich scientific heritage Argonne's Experimental Breeder Reactor-I in Idaho lit was December 20, 1951. Argonne National Laboratory is a U.S. Department of Energy laboratory managed by UChicago Argonne, LLC October 2010Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL 60439

Kemner, Ken

197

Solar Models and NACRE thermonuclear reaction rates  

E-Print Network [OSTI]

Using the most recent updated physics, calibrated solar models have been computed with the new thermonuclear reaction rates of NACRE, the recently available European compilation. Comparisons with models computed with the reaction rates of Caughlan & Fowler (\\cite{cf88}) and of Adelberger et al. (\\cite{a98}) are made for global structure, expected neutrinos fluxes, chemical composition and sound speed profiles, helioseismological properties of p-modes and g-modes.

P. Morel; B. Pichon; J. Provost; G. Berthomieu

1999-07-27T23:59:59.000Z

198

Experimental and Analytic Study on the Core Bypass Flow in a Very High Temperature Reactor  

SciTech Connect (OSTI)

Core bypass flow has been one of key issues in the very high temperature reactor (VHTR) design for securing core thermal margins and achieving target temperatures at the core exit. The bypass flow in a prismatic VHTR core occurs through the control element holes and the radial and axial gaps between the graphite blocks for manufacturing and refueling tolerances. These gaps vary with the core life cycles because of the irradiation swelling/shrinkage characteristic of the graphite blocks such as fuel and reflector blocks, which are main components of a core's structure. Thus, the core bypass flow occurs in a complicated multidimensional way. The accurate prediction of this bypass flow and counter-measures to minimize it are thus of major importance in assuring core thermal margins and securing higher core efficiency. Even with this importance, there has not been much effort in quantifying and accurately modeling the effect of the core bypass flow. The main objectives of this project were to generate experimental data for validating the software to be used to calculate the bypass flow in a prismatic VHTR core, validate thermofluid analysis tools and their model improvements, and identify and assess measures for reducing the bypass flow. To achieve these objectives, tasks were defined to (1) design and construct experiments to generate validation data for software analysis tools, (2) determine the experimental conditions and define the measurement requirements and techniques, (3) generate and analyze the experimental data, (4) validate and improve the thermofluid analysis tools, and (5) identify measures to control the bypass flow and assess its performance in the experiment.

Richard Schultz

2012-04-01T23:59:59.000Z

199

Thermonuclear processes of the Universe  

E-Print Network [OSTI]

The book considers some theoretical questions of nuclear astro-physics thermal energies and light atomic nuclei. For the analysis of re-actions is used potential two cluster model of light nuclei with classifica-tion of states by orbital schemes. On its basis photonuclear processes in p2H, p3H, p6Li, p7Li, p9Be and p12C, and also 2H4He, 3H4He, 3He4He and 4He12C channels are considered and astrophysical S - factors corre-sponding to them are calculated. It is shown, that used methods allow to describe well available experimental data in the field of astrophysical energies. This Book is written in Russian, but will perhaps present certain interest.

Sergey B. Dubovichenko

2011-08-12T23:59:59.000Z

200

THE POWER OF THERMONUCLEAR SUPERNOVAE AFTER ONE YEAR.  

E-Print Network [OSTI]

??Type Ia supernovae (SNe Ia), the thermonuclear explosion of a white dwarf, shape our understanding of the expansion of the universe with the use of… (more)

Bryngelson, Ginger

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermonuclear experimental 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

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

SciTech Connect (OSTI)

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

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

1997-03-01T23:59:59.000Z

202

Experimental Results from an Antineutrino Detector for Cooperative Monitoring of Nuclear Reactors  

SciTech Connect (OSTI)

Our collaboration has designed, installed, and operated a compact antineutrino detector at a nuclear power station, for the purpose of monitoring the power and plutonium content of the reactor core. This paper focuses on the basic properties and performance of the detector. We describe the site, the reactor source, and the detector, and provide data that clearly show the expected antineutrino signal. Our data and experience demonstrate that it is possible to operate a simple, relatively small, antineutrino detector near a reactor, in a non-intrusive and unattended mode for months to years at a time, from outside the reactor containment, with no disruption of day-to-day operations at the reactor site. This unique real-time cooperative monitoring capability may be of interest for the International Atomic Energy Agency (IAEA) reactor safeguards program and similar regimes.

Bowden, N S; Bernstein, A; Allen, M; Brennan, J S; Cunningham, M; Estrada, J K; Greaves, C R; Hagmann, C; Lund, J; Mengesha, W; Weinbeck, T D; Winant, C D

2006-09-18T23:59:59.000Z

203

agesta reactor: Topics by E-print Network  

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

of a severe unprotected (more) DeWitte, Jacob D. (Jacob Dominic) 2011-01-01 16 Thermonuclear Reflect AB-Reactor Physics (arXiv) Summary: The author offers a new kind of...

204

Control of tearing modes in toroidal fusion experiments using ``designer'' error fields  

E-Print Network [OSTI]

experimental results strongly suggest that further progress in obtaining thermonuclear reactor grade plasmas, placing feedback coils this close to a thermonuclear plasma is essentially impossible in a reactor

Rossi, Enrico

205

Probing thermonuclear supernova explosions with neutrinos  

E-Print Network [OSTI]

Aims: We present neutrino light curves and energy spectra for two representative type Ia supernova explosion models: a pure deflagration and a delayed detonation. Methods: We calculate the neutrino flux from $\\beta$ processes using nuclear statistical equilibrium abundances convoluted with approximate neutrino spectra of the individual nuclei and the thermal neutrino spectrum (pair+plasma). Results: Although the two considered thermonuclear supernova explosion scenarios are expected to produce almost identical electromagnetic output, their neutrino signatures appear vastly different, which allow an unambiguous identification of the explosion mechanism: a pure deflagration produces a single peak in the neutrino light curve, while the addition of the second maximum characterizes a delayed-detonation. We identified the following main contributors to the neutrino signal: (1) weak electron neutrino emission from electron captures (in particular on the protons Co55 and Ni56) and numerous beta-active nuclei produced by the thermonuclear flame and/or detonation front, (2) electron antineutrinos from positron captures on neutrons, and (3) the thermal emission from pair annihilation. We estimate that a pure deflagration supernova explosion at a distance of 1 kpc would trigger about 14 events in the future 50 kt liquid scintillator detector and some 19 events in a 0.5 Mt water Cherenkov-type detector. Conclusions: While in contrast to core-collapse supernovae neutrinos carry only a very small fraction of the energy produced in the thermonuclear supernova explosion, the SN Ia neutrino signal provides information that allows us to unambiguously distinguish between different possible explosion scenarios. These studies will become feasible with the next generation of proposed neutrino observatories.

A. Odrzywolek; T. Plewa

2011-03-27T23:59:59.000Z

206

The Fractional Kinetic Equation and Thermonuclear Functions  

E-Print Network [OSTI]

The paper discusses the solution of a simple kinetic equation of the type used for the computation of the change of the chemical composition in stars like the Sun. Starting from the standard form of the kinetic equation it is generalized to a fractional kinetic equation and its solutions in terms of H-functions are obtained. The role of thermonuclear functions, which are also represented in terms of G- and H-functions, in such a fractional kinetic equation is emphasized. Results contained in this paper are related to recent investigations of possible astrophysical solutions of the solar neutrino problem.

H. J. Haubold; A. M. Mathai

2000-01-16T23:59:59.000Z

207

aspects experimental developments: Topics by E-print Network  

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

Amit 10 PUBLISHED VERSION Design, performance, and grounding aspects of the International Thermonuclear Experimental Plasma Physics and Fusion Websites Summary: PUBLISHED VERSION...

208

Experimental method for reactor-noise measurements of effective beta. [LMFBR  

SciTech Connect (OSTI)

A variance-to-mean noise technique, modified to eliminate systematic errors from drifting of reactor power, has been used to infer integral values of effective beta for uranium and plutonium fueled fast reactor modk-ups. The measurement technique, including corrections for a finite detector-electrometer time response, is described together with preliminary beta measurement results.

Bennett, E.F.

1981-09-01T23:59:59.000Z

209

E-Print Network 3.0 - astrophysical thermonuclear reactions Sample...  

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

thermonuclear reactions Search Powered by Explorit Topic List Advanced Search Sample search results for: astrophysical thermonuclear reactions Page: << < 1 2 3 4 5 > >> 1 Workshop...

210

E-Print Network 3.0 - alamos thermonuclear weapon Sample Search...  

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

thermonuclear weapon Search Powered by Explorit Topic List Advanced Search Sample search results for: alamos thermonuclear weapon Page: << < 1 2 3 4 5 > >> 1 Dr. Lodwick's research...

211

E-Print Network 3.0 - atypical thermonuclear supernovae Sample...  

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

thermonuclear supernovae Search Powered by Explorit Topic List Advanced Search Sample search results for: atypical thermonuclear supernovae Page: << < 1 2 3 4 5 > >> 1 Supernova...

212

The physics of antimatter induced fusion and thermonuclear explosions  

E-Print Network [OSTI]

The feasibility of using antihydrogen for igniting inertial confinement fusion pellets or triggering large scale thermonuclear explosions is investigated. The number of antiproton annihilations required to start a thermonuclear burn wave in either DT or Li2DT is found to be about 10 21 /k 2, where

Andre Gsponer; Jean-pierre Hurni

213

Oscillations During Thermonuclear X-ray Bursts  

E-Print Network [OSTI]

High amplitude, nearly coherent X-ray brightness oscillations during thermonuclear X-ray bursts were discovered with the Rossi X-ray Timing Explorer (RXTE) in early 1996. Spectral and timing evidence strongly supports the conclusion that these oscillations are caused by rotational modulation of the burst emission and that they reveal the spin frequency of neutron stars in low mass X-ray binaries, a long sought goal of X-ray astronomy. Studies carried out over the past year have led to the discovery of burst oscillations in four new sources, bringing to ten the number with confirmed burst oscillations. I review the status of our knowledge of these oscillations and indicate how they can be used to probe the physics of neutron stars. For a few burst oscillation sources it has been proposed that the strongest and most ubiquitous frequency is actually the first overtone of the spin frequency and hence that two nearly antipodal hot spots are present on the neutron star. This inference has important implications for both the physics of thermonuclear burning as well as the mass- radius relation for neutron stars, so its confirmation is crucial. I discuss recent attempts to confirm this hypothesis for 4U 1636-53, the source for which a signal at the putative fundamental (290 Hz) has been claimed.

Tod E. Strohmayer

2001-01-01T23:59:59.000Z

214

Oscillations During Thermonuclear X-ray Bursts  

E-Print Network [OSTI]

High amplitude, nearly coherent X-ray brightness oscillations during thermonuclear X-ray bursts were discovered with the Rossi X-ray Timing Explorer (RXTE) in early 1996. Spectral and timing evidence strongly supports the conclusion that these oscillations are caused by rotational modulation of the burst emission and that they reveal the spin frequency of neutron stars in low mass X-ray binaries, a long sought goal of X-ray astronomy. Studies carried out over the past year have led to the discovery of burst oscillations in four new sources, bringing to ten the number with confirmed burst oscillations. I review the status of our knowledge of these oscillations and indicate how they can be used to probe the physics of neutron stars. For a few burst oscillation sources it has been proposed that the strongest and most ubiquitous frequency is actually the first overtone of the spin frequency and hence that two nearly antipodal hot spots are present on the neutron star. This inference has important implications for both the physics of thermonuclear burning as well as the mass - radius relation for neutron stars, so its confirmation is crucial. I discuss recent attempts to confirm this hypothesis for 4U 1636-53, the source for which a signal at the putative fundamental (290 Hz) has been claimed.

Tod E. Strohmayer

2001-01-12T23:59:59.000Z

215

Wideband Heterodyne QWIP Receiver Development for Thermonuclear Fusion Measurements  

SciTech Connect (OSTI)

Oak Ridge National Laboratory (ORNL) has been developing heterodyne receivers for plasma diagnostic applications for over 20 years. One area of this work has been the development of a diagnostic system for the measurement of the energy of alpha particles created in a thermonuclear fusion reactor. These particles originate with an energy of 3.5 MeV and cool to the thermal energy of the plasma (around 15 keV) after several seconds. To measure the velocity distribution of these alpha particles, a Thomson scattering diagnostic is under development based on a high power CO{sub 2} laser at 10 microns with a heterodyne receiver. The Doppler shift generated by Thomson scattering of the alpha particles requires a wideband heterodyne receiver (greater than 10 GHz). Because Mercury-Cadimum-Telluride (MCT) detectors are limited to a bandwidth of approximately 2 GHz, a Quantum Well Infrared Photodetector (QWIP) detector was obtained from the National Research Council of Canada (NRC) and evaluated for its heterodyne performance using the heterodyne testing facility developed at ORNL.

Bennett, C.A.; Buchanan, M.; Hutchinson, D.P.; Liu, H.C.; Richards, R.K.; Simpson, M.L.

1998-11-01T23:59:59.000Z

216

Experimental and Thermalhydraulic Code Assessment of the Transient Behavior of the Passive Condenser System in an Advanced Boiling Water Reactor  

SciTech Connect (OSTI)

The main goal of the project was to study analytically and experimentally the condensation heat transfer for the passive condenser system such as GE Economic Simplified Boiling Water Reactor (ESBWR). The effect of noncondensable gas in condenser tube and the reduction of secondary pool water level to the condensation heat transfer coefficient was the main focus in this research. The objectives of this research were to : 1) obtain experimental data on the local and tube averaged condensation heat transfer rates for the PCCS with non-condensable and with change in the secondary pool water, 2) assess the RELAP5 and TRACE computer code against the experimental data, and 3) develop mathematical model and ehat transfer correlation for the condensation phenomena for system code application. The project involves experimentation, theoretical model development and verification, and thermal- hydraulic codes assessment.

S.T. Revankar; W. Zhou; Gavin Henderson

2008-07-08T23:59:59.000Z

217

70 IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 18, NO. 2, JUNE 2008 High Field Superconducting Solenoids Via High  

E-Print Network [OSTI]

an essential role in fusion devices, including the Interna- tional Thermonuclear Experimental Reactor [6], [7

218

Ris-R-1276(EN) Final Report  

E-Print Network [OSTI]

Thermonuclear Experimental Reactor) [1,2]. Since very little was known about the effect of irradiation

219

INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION BEAMS  

E-Print Network [OSTI]

Thermonuclear Experimental Reactor), now being constructed in Caderache, France [5]. In contrast, inertial fusion

Sharp, W. M.

2011-01-01T23:59:59.000Z

220

Subchannel Thermal-Hydraulic Experimental Program (STEP). Volume 1. Mixing in a pressurized water reactor (PWR) rod bundle. Final report  

SciTech Connect (OSTI)

This volume describes an experiment that was performed to determine the mixing characteristics of a pressurized water reactor (PWR) rod bundle. The objective of this project was to improve the subchannel computer code models of the reactor core. The experimental technique was isokinetic subchannel withdrawal of the entire flow from two sample subchannels. Once withdrawn, the sample fluid was condensed and its enthalpy was measured by regenerative heat exchange calorimetry. The test bundle was a 4 x 6 electrically heated array with a 50% power upset. The COBRA IIIC code was used to model the experiment and to determine the value of the thermal mixing coefficient, ..beta.., that was necessary to predict the measured results. Both single- and two-phase data were obtained over a range of PWR operating conditions. The results indicate that both single- and two-phase mixing is small. The COBRA model predicts the enthalpy data using a turbulent mixing coefficient, ..beta.. approx. = 0.002.

Barber, A.R.; Zielke, L.A.

1980-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermonuclear experimental 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

Japan considers conceding ITER site to France TOKYO, May 4, Kyodo -(EDS: UPDATING WITH MACHIMURA MEETING WITH BARNIER IN  

E-Print Network [OSTI]

the planned International Thermonuclear Experimental Reactor in Rokkasho, Aomori Prefecture, and bowing out plant is an experimental facility of thermonuclear fusion, at which nuclear fusion reactions that occur

222

EXTENSION OF THERMONUCLEAR FUNCTIONS THROUGH THE PATHWAY MODEL INCLUDING MAXWELL-BOLTZMANN AND  

E-Print Network [OSTI]

of respective thermonuclear functions is being conducted with the help of statistical techniques. The

H. J. Haubold

223

Measurement of the Fractional Thermonuclear Neutron Yield during Deuterium Neutral-Beam Injection into Deuterium Plasmas  

E-Print Network [OSTI]

Measurement of the Fractional Thermonuclear Neutron Yield during Deuterium Neutral-Beam Injection into Deuterium Plasmas

224

explosion: Role of hydrogen thermonuclear explosion in support of cometary hypothesis  

E-Print Network [OSTI]

deuteron fusion rates and that a thermonuclear explosion may compete with a thermo-chemical explosion

Y. E. Kim

2008-01-01T23:59:59.000Z

225

Numerical simulations of welds of thick steel pieces of interest for the thermonuclear fusion ITER machine  

E-Print Network [OSTI]

Numerical simulations of welds of thick steel pieces of interest for the thermonuclear fusion ITER machine

Carmignani, B

2005-01-01T23:59:59.000Z

226

The physics of antimatter induced fusion and thermonuclear explosions  

E-Print Network [OSTI]

The possibility of using antihydrogen for igniting inertial confinement fusion pellets or triggering large scale thermonuclear explosions is investigated. The number of antiproton annihilations required to start a thermonuclear burn wave in either D or Li_2DT is found to be about 10^{21}/k^2, where k is the compression factor of the fuel to be ignited. We conclude that the financial and energy investments needed to produce such amounts of antiprotons would confine applications of antimatter triggered thermonuclear devices to the military domain.

Gsponer, A; Gsponer, Andre; Hurni, Jean-Pierre

1987-01-01T23:59:59.000Z

227

Thermonuclear 42Ti(p,gamma)43V rate in type I X-ray bursts  

E-Print Network [OSTI]

The thermonuclear rate of the $^{42}$Ti($p$,$\\gamma$)$^{43}$V reaction has been reevaluated based on a recent precise proton separation energy measurement of $S_p$($^{43}$V)=83$\\pm$43 keV. The astrophysical impact of our new rates has been investigated through one-zone postprocessing type I x-ray burst calculations. It shows that the new experimental value of $S_p$ significantly affects the yields of species between A$\\approx$40--45. As well, the precision of the recent experimental $S_p$ value constrains these yields to better than a factor of three.

He, J J; Brown, B A; Rauscher, T; Hou, S Q; Zhang, Y H; Zhou, X H; Xu, H S

2014-01-01T23:59:59.000Z

228

Thermonuclear Reaction Rate of 23Mg(p,gamma)24$Al  

E-Print Network [OSTI]

Updated stellar rates for the reaction 23Mg(p,gamma)24Al are calculated by using all available experimental information on 24Al excitation energies. Proton and gamma-ray partial widths for astrophysically important resonances are derived from shell model calculations. Correspondences of experimentally observed 24Al levels with shell model states are based on application of the isobaric multiplet mass equation. Our new rates suggest that the 23Mg(p,gamma)24Al reaction influences the nucleosynthesis in the mass A>20 region during thermonuclear runaways on massive white dwarfs.

H. Herndl; M. Fantini; C. Iliades; P. M. Endt; H. Oberhummer

1998-06-05T23:59:59.000Z

229

Thermonuclear 42Ti(p,gamma)43V rate in type I X-ray bursts  

E-Print Network [OSTI]

The thermonuclear rate of the $^{42}$Ti($p$,$\\gamma$)$^{43}$V reaction has been reevaluated based on a recent precise proton separation energy measurement of $S_p$($^{43}$V)=83$\\pm$43 keV. The astrophysical impact of our new rates has been investigated through one-zone postprocessing type I x-ray burst calculations. It shows that the new experimental value of $S_p$ significantly affects the yields of species between A$\\approx$40--45. As well, the precision of the recent experimental $S_p$ value constrains these yields to better than a factor of three.

J. J. He; A. Parikh; B. A. Brown; T. Rauscher; S. Q. Hou; Y. H. Zhang; X. H. Zhou; H. S. Xu

2014-03-10T23:59:59.000Z

230

explosion: Role of hydrogen thermonuclear explosion in support of cometary hypothesis  

E-Print Network [OSTI]

comet, compressional heating of the comet was expected to create hydrogen and deuterium plasma. The velocity distribution of protons and deuterons in this plasma is not expected to be the Maxwell-Boltzmann distribution. It is shown that the use of a generalized momentum distribution leads to substantial increases of deuteron fusion rates and that a thermonuclear explosion may compete with a thermo-chemical explosion. Therefore, it may be possible that a thermo-chemical explosion induced a hydrogen thermonuclear explosion and both the thermo-chemical and thermonuclear explosions occurred in the 1908 Tunguska event. Experimental tests of this hypothesis are proposed. The explosion on 30 June 1908 over Tunguska, Central Siberia, released 30 megatons (TNT equivalent) of energy at an altitude of 5 km without creating crater(s) on the Earth’s surface. Many hypotheses (antimatter, a small black hole, carbonaceous asteroids, comets, etc.) have been proposed. Recent measurements of anomalous isotope ratios in the 1908 peat layers at and near the epicenter have ruled out most of the proposed hypotheses, and provide many supporting evidences for the cometary hypothesis [1]. The cometary core consists mostly of frozen ice. Compressional heating explosion of falling cometary bodies in the atmosphere was proposed as early as in 1930, and has been investigated theoretically [1]. A

Y. E. Kim

2008-01-01T23:59:59.000Z

231

Modeling Combustion in Current Candidate Scenarios for Thermonuclear...  

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

Combustion in Current Candidate Scenarios for Thermonuclear Supernovae Mar 26 2015 03:00 PM - 04:00 PM Dean M. Townsley, The University of Alabama, Tuscaloosa Physics Division...

232

Study of Thermonuclear Alfven Instabilities in Next Step Burning Plasma Experiments  

SciTech Connect (OSTI)

A study is presented for the stability of alpha-particle driven shear Alfven Eigenmodes (AE) for the normal parameters of the three major burning plasma proposals, ITER (International Thermonuclear Experimental Reactor), FIRE (Fusion Ignition Research Experiment), and IGNITOR (Ignited Torus). A study of the JET (Joint European Torus) plasma, where fusion alphas were generated in tritium experiments, is also included to attempt experimental validation of the numerical predictions. An analytic assessment of Toroidal AE (TAE) stability is first presented, where the alpha particle beta due to the fusion reaction rate and electron drag is simply and accurately estimated in 7-20 keV plasma temperature regime. In this assessment the hot particle drive is balanced against ion-Landau damping of the background deuterons and electron collision effects and stability boundaries are determined. Then two numerical studies of AE instability are presented. In one the High-n stability code HINST is used . This code is capable of predicting instabilities of low and moderately high frequency Alfven modes. HINST computes the non-perturbative solution of the Alfven eigenmodes including effects of ion finite Larmor radius, orbit width, trapped electrons etc. The stability calculations are repeated using the global code NOVAK. We show that for these tokamaks the spectrum of the least stable AE modes are TAE that appear at medium-/high-n numbers. In HINST TAEs are locally unstable due to the alphas pressure gradient in all the devices under the consideration except IGNITOR. However, NOVAK calculations show that the global mode structure enhances the damping mechanisms and produces stability in all configurations considered here. A serious question remains whether the perturbation theory used in NOVAK overestimates the stability predictions, so that it is premature to conclude that the nominal operation of all three proposals are stable to AEs. In addition NBI ions produce a strong stabilizing effect for JET. However, in ITER the beam energies needed to penetrate to the core must be high so that a diamagnetic drift frequency comparable to that of the alpha particles is produced by the beam ions which induces a destabilizing effect.

N.N. Gorelenkov; H.L. Berk; R. Budny; C.Z. Cheng; G.-Y. Fu; W.W. Heidbrink; G. Kramer; D. Meade; and R. Nazikian

2002-07-02T23:59:59.000Z

233

Automated operator procedure prompting for startup of Experimental Breeder Reactor-2  

SciTech Connect (OSTI)

This report describes the development of an operator procedure prompting aid for startup of a nuclear reactor. This operator aid is a preliminary design for a similar aid that eventually will be used with the Advanced Liquid Metal Reactor (ALMR) presently in the design stage. Two approaches were used to develop this operator procedure prompting aid. One method uses an expert system software shell, and the other method uses database software. The preliminary requirements strongly pointed toward features traditionally associated with both database and expert systems software. Database software usually provides data manipulation flexibility and user interface tools, and expert systems tools offer sophisticated data representation and reasoning capabilities. Both methods, including software and associated hardware, are described in this report. Proposals for future enhancements to improve the expert system approach to procedure prompting and for developing other operator aids are also offered. 25 refs., 14 figs.

Renshaw, A.W.; Ball, S.J.; Ford, C.E.

1990-11-01T23:59:59.000Z

234

Modeling and Experimental Studies of Mercury Oxidation and Adsorption in a Fixed-Bed and Entrained-Flow Reactor  

SciTech Connect (OSTI)

This report presents experimental and modeling mercury oxidation and adsorption data. Fixed-bed and single-particle models of mercury adsorption were developed. The experimental data were obtained with two reactors: a 300-W, methane-fired, tubular, quartz-lined reactor for studying homogeneous oxidation reactions and a fixed-bed reactor, also of quartz, for studying heterogeneous reactions. The latter was attached to the exit of the former to provide realistic combustion gases. The fixed-bed reactor contained one gram of coconut-shell carbon and remained at a temperature of 150oC. All methane, air, SO2, and halogen species were introduced through the burner to produce a radical pool representative of real combustion systems. A Tekran 2537A Analyzer coupled with a wet conditioning system provided speciated mercury concentrations. At 150?C and in the absence of HCl or HBr, the mercury uptake was about 20%. The addition of 50 ppm HCl caused complete capture of all elemental and oxidized mercury species. In the absence of halogens, SO2 increased the mercury adsorption efficiency to up to 30 percent. The extent of adsorption decreased with increasing SO2 concentration when halogens were present. Increasing the HCl concentration to 100 ppm lessened the effect of SO2. The fixed-bed model incorporates Langmuir adsorption kinetics and was developed to predict adsorption of elemental mercury and the effect of multiple flue gas components. This model neglects intraparticle diffusional resistances and is only applicable to pulverized carbon sorbents. It roughly describes experimental data from the literature. The current version includes the ability to account for competitive adsorption between mercury, SO2, and NO2. The single particle model simulates in-flight sorbent capture of elemental mercury. This model was developed to include Langmuir and Freundlich isotherms, rate equations, sorbent feed rate, and intraparticle diffusion. The Freundlich isotherm more accurately described in-flight mercury capture. Using these parameters, very little intraparticle diffusion was evident. Consistent with other data, smaller particles resulted in higher mercury uptake due to available surface area. Therefore, it is important to capture the particle size distribution in the model. At typical full-scale sorbent feed rates, the calculations underpredicted adsorption, suggesting that wall effects can account for as much as 50 percent of the removal, making it an important factor in entrained-mercury adsorption models.

Buitrago, Paula A; Morrill, Mike; Lighty, JoAnn S; Silcox, Geoffrey D

2014-08-20T23:59:59.000Z

235

Experimental investigation into fast pyrolysis of biomass using an entrained-flow reactor  

SciTech Connect (OSTI)

Pyrolysis experiments were performed using 30 and 90cm entrained-flow reactors, with steam as a carrier gas and two different feedstocks - wheat straw and powdered material drived from municipal solid waste (ECO-II TM). Reactor wall temperature was varied from 700/sup 0/ to 1400/sup 0/C. Gas composition data from the ECO-II tests were comparable to previously reported data but ethylene yield appeared to vary with reactor wall temperature and residence time. The important conclusion from the wheat straw tests is that olefin yields are about one half that obtained from ECO-II. Evidence was found that high olefin yields from ECO-II are due to the presence of plastics in the feedstock. Batch experiments were run on wheat straw using a Pyroprobe/sup TM/. The samples were heated at a high rate (20,000/sup 0/ C/sec) to 1000/sup 0/ and held at 1000/sup 0/C for a variable period of time from 0.05 to 4.95s. For times up to 0.15s volume fractions of ethylene, propylene, and methane increase while that of carbon dioxide decreases. Subsequently, only carbon monoxide and hydrogen are produced. The change may be related to poor thermal contact and suggests caution in using the Pyroprobe.

Bohn, M.; Benham, C.

1981-02-01T23:59:59.000Z

236

Experimental Study of the Thermal-Hydraulic Phenomena in the Reactor Cavity Cooling System and Analysis of the Effects of Graphite Dispersion  

E-Print Network [OSTI]

An experimental activity was performed to observe and study the effects of graphite dispersion and deposition on thermal hydraulic phenomena in a Reactor Cavity Cooling System (RCCS). The small scale RCCS experimental facility (16.5cm x 16.5cm x 30...

Vaghetto, Rodolfo

2012-07-16T23:59:59.000Z

237

Experimental Study of the Effect of Graphite Dispersion on the Heat Transfer Phenomena in a Reactor Cavity Cooling System  

SciTech Connect (OSTI)

An experimental activity was performed to observe and study the effects of graphite dispersion and deposition on thermal-hydraulic phenomena in a reactor cavity cooling system (RCCS). The small-scale RCCS experimental facility (16.5 x 16.5 x 30.4 cm) used for this activity represents half of the reactor cavity with an electrically heated vessel. Water flowing through five vertical pipes removes the heat produced in the vessel and releases it into the environment by mixing with cold water in a large tank. The particle image velocimetry technique was used to study the velocity field of the air inside the cavity. A set of 52 thermocouples was installed in the facility to monitor the temperature profiles of the vessel, pipe walls, and air. Ten grams of a fine graphite powder (average particle size 2 m) was injected into the cavity through a spraying nozzle placed at the bottom of the vessel. The temperatures and air velocity field were recorded and compared with the measurements obtained before the graphite dispersion, showing a decrease of the temperature surfaces that was related to an increase in their emissivity. The results contribute to the understanding of RCCS capability in an accident scenario.

Rodolfo Vaghetto; Luigi Capone; Yassin A. Hassan

2011-05-31T23:59:59.000Z

238

Development and experimental validation of a calculation scheme for nuclear heating evaluation in the core of the OSIRIS material testing reactor  

SciTech Connect (OSTI)

The control of the temperature in material samples irradiated in a material testing reactor requires the knowledge of the nuclear heating caused by the energy deposition by neutrons and photons interacting in the irradiation device structures. Thus, a neutron-photonic three-dimensional calculation scheme has been developed to evaluate the nuclear heating in experimental devices irradiated in the core of the OSIRIS MTR reactor (CEA/Saclay Center). The aim is to obtain a predictive tool for the nuclear heating estimation in irradiation devices. This calculation scheme is mainly based on the TRIPOLI-4 three-dimensional continuous-energy Monte Carlo transport code, developed by CEA (Saclay Center). An experimental validation has been carried out on the basis of nuclear heating measurements performed in the OSIRIS core. After an overview of the experimental devices irradiated in the OSIRIS reactor, we present the calculation scheme and the first results of the experimental validation. (authors)

Malouch, F. [Saclay Center CEA, DEN/DANS/DM2S/SERMA, F-91191 Gif-sur-Yvette Cedex (France)

2011-07-01T23:59:59.000Z

239

Thermonuclear supernova simulations with stochastic ignition  

E-Print Network [OSTI]

We apply an ad hoc model for dynamical ignition in three-dimensional numerical simulations of thermonuclear supernovae assuming pure deflagrations. The model makes use of the statistical description of temperature fluctuations in the pre-supernova core proposed by Wunsch & Woosley (2004). Randomness in time is implemented by means of a Poisson process. We are able to vary the explosion energy and nucleosynthesis depending on the free parameter of the model which controls the rapidity of the ignition process. However, beyond a certain threshold, the strength of the explosion saturates and the outcome appears to be robust with respect to number of ignitions. In the most energetic explosions, we find about 0.75 solar masses of iron group elements. Other than in simulations with simultaneous multi-spot ignition, the amount of unburned carbon and oxygen at radial velocities of a few 1000 km/s tends to be reduced for an ever increasing number of ignition events and, accordingly, more pronounced layering results.

W. Schmidt; J. C. Niemeyer

2005-10-14T23:59:59.000Z

240

The development and operational testing of an experimental reactor for gas-liquid-solid reaction systems at high temperatures and pressures  

E-Print Network [OSTI]

shaft. With the impeller in place and rotating, gas was drawn into the top port and ejected at the impeller mount. The reactor pressure was monitored via the transducer port. The transducer was a Viatran Pressure Transducer, model 103. The liquid...THE DEVELOPMENT AND OPERATIONAL TESTING OF AN EXPERIMENTAL REACTOR FOR GAS-LIQUID-SOLID REACTION SYSTEMS AT HIGH TEMPERATURES AND PRESSURES A Thesis by RICHARD KENNETH HESS Submitted to the Graduate College of Texas A&M University in partial...

Hess, Richard Kenneth

2012-06-07T23:59:59.000Z

Note: This page contains sample records for the topic "thermonuclear experimental 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

Experimental Development and Demonstration of Ultrasonic Measurement Diagnostics for Sodium Fast Reactor Thermal-hydraulics  

SciTech Connect (OSTI)

This research project will address some of the principal technology issues related to sodium-cooled fast reactors (SFR), primarily the development and demonstration of ultrasonic measurement diagnostics linked to effective thermal convective sensing under normatl and off-normal conditions. Sodium is well-suited as a heat transfer medium for the SFR. However, because it is chemically reactive and optically opaque, it presents engineering accessibility constraints relative to operations and maintenance (O&M) and in-service inspection (ISI) technologies that are currently used for light water reactors. Thus, there are limited sensing options for conducting thermohydraulic measurements under normal conditions and off-normal events (maintenance, unanticipated events). Acoustic methods, primarily ultrasonics, are a key measurement technology with applications in non-destructive testing, component imaging, thermometry, and velocimetry. THis project would have yielded a better quantitative and qualitative understanding of the thermohydraulic condition of solium under varied flow conditions. THe scope of work will evaluate and demonstrate ultrasonic technologies and define instrumentation options for the SFR.

Tokuhiro, Akira; Jones, Byron

2013-09-13T23:59:59.000Z

242

Experimental characterization of an Ion Transport Membrane (ITM) reactor for methane oxyfuel combustion  

E-Print Network [OSTI]

Ion Transport Membranes (ITM) which conduct both electrons and oxygen ions have been investigated experimentally for oxygen separation and fuel (mostly methane) conversion purposes over the last three decades. The fuel ...

Apo, Daniel Jolomi

2012-01-01T23:59:59.000Z

243

Thermonuclear reaction rate of $^{18}$Ne($?$,$p$)$^{21}$Na from Monte-Carlo calculations  

E-Print Network [OSTI]

The $^{18}$Ne($\\alpha$,$p$)$^{21}$Na reaction impacts the break-out from the hot CNO-cycles to the $rp$-process in type I X-ray bursts. We present a revised thermonuclear reaction rate, which is based on the latest experimental data. The new rate is derived from Monte-Carlo calculations, taking into account the uncertainties of all nuclear physics input quantities. In addition, we present the reaction rate uncertainty and probability density versus temperature. Our results are also consistent with estimates obtained using different indirect approaches.

P. Mohr; R. Longland; C. Iliadis

2014-12-14T23:59:59.000Z

244

Thermonuclear reaction rate of $^{18}$Ne($\\alpha$,$p$)$^{21}$Na from Monte-Carlo calculations  

E-Print Network [OSTI]

The $^{18}$Ne($\\alpha$,$p$)$^{21}$Na reaction impacts the break-out from the hot CNO-cycles to the $rp$-process in type I X-ray bursts. We present a revised thermonuclear reaction rate, which is based on the latest experimental data. The new rate is derived from Monte-Carlo calculations, taking into account the uncertainties of all nuclear physics input quantities. In addition, we present the reaction rate uncertainty and probability density versus temperature. Our results are also consistent with estimates obtained using different indirect approaches.

Mohr, P; Iliadis, C

2014-01-01T23:59:59.000Z

245

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

SciTech Connect (OSTI)

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

Shripad T. Revankar; Seungmin Oh

2003-09-30T23:59:59.000Z

246

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

SciTech Connect (OSTI)

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

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

1996-06-01T23:59:59.000Z

247

MASSACHUSETTS INSTITUTE OF TECHNOLOGY PLASMA FUSI0.N CENTER  

E-Print Network [OSTI]

. The International Thermonuclear Experimental Reactor (ITER), a superconducting device, is being designed to achieve transport processes and alpha heating effectiveness,[2] at the re- quired thermonuclear conditions

248

Ris-R-1007(EN) Influence of Composition, Heat  

E-Print Network [OSTI]

Thermonuclear Experimental Reactor). The alloys have undergone different pre-irradiation heat treatments which- eration for their applications in the structural components of ITER (Inter- national Thermonuclear

249

arabidopsis converts benzaldehyde: Topics by E-print Network  

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

CERN Preprints Summary: The International Thermonuclear Experimental Reactor (ITER) is a thermonuclear fusion experiment designed to provide long deuterium tritium burning...

250

ac-line matrix-reactance converter: Topics by E-print Network  

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

CERN Preprints Summary: The International Thermonuclear Experimental Reactor (ITER) is a thermonuclear fusion experiment designed to provide long deuterium tritium burning...

251

Magnetic Braids Anthony Yeates  

E-Print Network [OSTI]

flux function Main result Conclusion 2. Thermonuclear confinement devices. ITER (Internat'l Thermonuclear Experimental Reactor). Inside the KSTAR tokamak. Correspond to periodic magnetic braids. 4 / 22

Dundee, University of

252

A time-delay approach for the modeling and control of plasma instabilities in thermonuclear fusion  

E-Print Network [OSTI]

1 A time-delay approach for the modeling and control of plasma instabilities in thermonuclear for thermonuclear fusion plasmas. Indeed, advanced plasma confinement scenarios, such as the ones considered

Sipahi, Rifat

253

Thermonuclear Supernovae: Simulations of the Deflagration Stage and Their Implications  

E-Print Network [OSTI]

Large-scale three-dimensional numerical simulations of the deflagration stage of a thermonuclear supernova explosion show the formation and evolution of a highly convoluted turbulent flame in a gravitational field of an expanding carbon-oxygen white dwarf. The flame dynamics is dominated by the gravity-induced Rayleigh-Taylor instability that controls the burning rate. The thermonuclear deflagration releases enough energy to produce a healthy explosion. The turbulent flame, however, leaves large amounts of unburnt and partially burnt material near the star center, whereas observations imply these materials only in outer layers. This disagreement could be resolved if the deflagration triggers a detonation.

V. N. Gamezo; A. M. Khokhlov; E. S. Oran; A. Y. Chtchelkanova; R. O. Rosenberg

2002-12-03T23:59:59.000Z

254

Thermonuclear Fusion with the Sheared Flow Stabilized Z-Pinch  

E-Print Network [OSTI]

Two basic approaches to producing thermonuclear fusion with a sheared flow stabilized z-pinch are considered. One consists of heating the entire length of the z-pinch column to the required temperatures. The other basic approach considered here involves the concept of fast ignition. A localized "hot-spot" is produced under the proper conditions to ignite a thermonuclear burn wave in the z-pinch plasma. Here we demonstrate that sheared flow stabilization is more efficient in the fast-ignition method with isentropic compression then in a z-pinch where the entire plasma column is heated.

Winterberg, F

2008-01-01T23:59:59.000Z

255

First direct evidence that filament fracture accompanies degradation of superconducting cables designed for the  

E-Print Network [OSTI]

designed for the International Thermonuclear Experimental Reactor (ITER) ­ The tokomak fusion reactor ITER generation from nuclear fusion. Eighteen toroidal field coils, each weighing 363 tons, will confine High Magnetic Field Laboratory; 2. International Thermonuclear Experimental Reactor (ITER) Organization

Weston, Ken

256

Thermonuclear explosions of Chandrasekhar-mass C+O white dwarfs  

E-Print Network [OSTI]

thermonuclear burning, by means of a new two-dimensional numerical code. Since in the interior of such a massive

M. Reinecke; W. Hillebrandt

1998-01-01T23:59:59.000Z

257

Radiation Damage in Nuclear Fuel for Advanced Burner Reactors: Modeling and Experimental Validation  

SciTech Connect (OSTI)

The consortium has completed its existence and we are here highlighting work and accomplishments. As outlined in the proposal, the objective of the work was to advance the theoretical understanding of advanced nuclear fuel materials (oxides) toward a comprehensive modeling strategy that incorporates the different relevant scales involved in radiation damage in oxide fuels. Approaching this we set out to investigate and develop a set of directions: 1) Fission fragment and ion trajectory studies through advanced molecular dynamics methods that allow for statistical multi-scale simulations. This work also includes an investigation of appropriate interatomic force fields useful for the energetic multi-scale phenomena of high energy collisions; 2) Studies of defect and gas bubble formation through electronic structure and Monte Carlo simulations; and 3) an experimental component for the characterization of materials such that comparisons can be obtained between theory and experiment.

Jensen, Niels Gronbech; Asta, Mark; Ozolins, Nigel Browning'Vidvuds; de Walle, Axel van; Wolverton, Christopher

2011-12-29T23:59:59.000Z

258

France gets nuclear fusion plant France will get to host the project to build a 10bn-euro (6.6bn) nuclear fusion reactor, in  

E-Print Network [OSTI]

) nuclear fusion reactor, in the face of strong competition from Japan. The International Thermonuclear division, which is responsible for the UK's thermonuclear fusion programme, said the decisionFrance gets nuclear fusion plant France will get to host the project to build a 10bn-euro (£6.6bn

259

Thermonuclear Supernovae: Simulations of the Deflagration Stage and Their Implications  

E-Print Network [OSTI]

Large-scale three-dimensional numerical simulations of the deflagration stage of a thermonuclear supernova explosion show the formation and evolution of a highly convoluted turbulent flame in a gravitational field of an expanding carbon-oxygen white dwarf. The flame dynamics is dominated by the gravity-induced Rayleigh-Taylor instability that controls the burning rate. The thermonuclear deflagration releases enough energy to produce a healthy explosion. The turbulent flame, however, leaves large amounts of unburnt and partially burnt material near the star center, whereas observations imply these materials only in outer layers. This disagreement could be resolved if the deflagration triggers a detonation. 1 According to observations and models, many stars that steadily burn their nuclear fuel for millions or billions of years suddenly end their lives with a powerful explosion that produces a bright object called a supernova. A supernova explosion can be powered either by the gravitational energy released during the core collapse of a massive star, or by the nuclear energy released by explosive thermonuclear burning of a star. Here, we focus on thermonuclear supernovae that belong to the Type Ia (SN Ia) in the observation-based classification (1-3).

V. N. Gamezo; A. M. Khokhlov; E. S. Oran; A. Y. Chtchelkanova; R. O. Rosenberg

2003-01-01T23:59:59.000Z

260

The physics of antimatter induced fusion and thermonuclear explosions  

E-Print Network [OSTI]

The feasibility of using antihydrogen for igniting inertial confinement fusion pellets or triggering large scale thermonuclear explosions is investigated. The number of antiproton annihilations required to start a thermonuclear burn wave in either DT or Li2DT is found to be about 10 21 /k 2, where k is the compression factor of the fuel to be ignited. In the second part, the technologies for producing antiprotons with high energy accelerator systems and the means for manipulating and storing microgram amounts of antihydrogen are examined. While there seems to be no theoretical obstacles to the production of 10 18 antiprotons per day (the amount required for triggering one thermonuclear bomb), the construction of such a plant involves several techniques which are between 3 and 4 orders of magnitude away from present day technology. Considering the financial and energy investments needed to produce antimatter, applications will probably remain confined to the military domain. Since antihydrogen-triggered thermonuclear explosives are very compact and have extremely reduced fall-out, we conclude that such devices will enhance the proliferation of nuclear weapons and further diffuse the distinction between low-yield nuclear weapons and conventional explosives. 1

Andre Gsponer; Jean-pierre Hurni

Note: This page contains sample records for the topic "thermonuclear experimental 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

Thermonuclear Supernovae: Simulations of the Deflagration Stage and Their Implications  

E-Print Network [OSTI]

Large-scale three-dimensional numerical simulations of the deflagration stage of a thermonuclear supernova explosion show the formation and evolution of a highly convoluted turbulent flame in a gravitational field of an expanding carbon-oxygen white dwarf. The flame dynamics is dominated by the

V. N. Gamezo; A. M. Khokhlov; E. S. Oran; A. Y. Chtchelkanova; R. O. Rosenberg

2003-01-01T23:59:59.000Z

262

The LOFT perspective on neutron star thermonuclear bursts  

E-Print Network [OSTI]

This is a White Paper in support of the mission concept of the Large Observatory for X-ray Timing (LOFT), proposed as a medium-sized ESA mission. We discuss the potential of LOFT for the study of thermonuclear X-ray bursts on accreting neutron stars. For a summary, we refer to the paper.

Zand, J J M in 't; Ballantyne, D R; Bhattacharyya, S; Brown, E F; Cavecchi, Y; Chakrabarty, D; Chenevez, J; Cumming, A; Degenaar, N; Falanga, M; Galloway, D K; Heger, A; José, J; Keek, L; Linares, M; Mahmoodifar, S; Malone, C M; Méndez, M; Miller, M C; Paerels, F B S; Poutanen, J; Rózanska, A; Schatz, H; Serino, M; Strohmayer, T E; Suleimanov, V F; Thielemann, F -K; Watts, A L; Weinberg, N N; Woosley, S E; Yu, W; Zhang, S; Zingale, M

2015-01-01T23:59:59.000Z

263

Millisecond oscillations during thermonuclear X-ray bursts  

E-Print Network [OSTI]

I analyze 68 oscillation trains detected in a search of 159 thermonuclear bursts from eight neutron star X-ray binaries observed with the Rossi X-ray Timing Explorer. I use all data that were public as of September 2001. ...

Muno, Michael Patrick, 1975-

2002-01-01T23:59:59.000Z

264

The Effects of Thermonuclear Reaction Rate Variations on Nova Nucleosynthesis: A Sensitivity Study  

E-Print Network [OSTI]

We investigate the effects of thermonuclear reaction rate uncertainties on nova nucleosynthesis. One-zone nucleosynthesis calculations have been performed by adopting temperature-density-time profiles of the hottest hydrogen-burning zone (i.e., the region in which most of the nucleosynthesis takes place). We obtain our profiles from 7 different, recently published, hydrodynamic nova simulations covering peak temperatures in the range from Tpeak=0.145-0.418 GK. For each of these profiles, we individually varied the rates of 175 reactions within their associated errors and analyzed the resulting abundance changes of 142 isotopes in the mass range below A=40. In total, we performed 7350 nuclear reaction network calculations. We use the most recent thermonuclear reaction rate evaluations for the mass ranges A=1-20 and A=20-40. For the theoretical astrophysicist, our results indicate the extent to which nova nucleosynthesis calculations depend on presently uncertain nuclear physics input, while for the experimental nuclear physicist our results represent at least a qualitative guide for future measurements at stable and radioactive ion beam facilities. We find that present reaction rate estimates are reliable for predictions of Li, Be, C and N abundances in nova nucleosynthesis. However, rate uncertainties of several reactions have to be reduced significantly in order to predict more reliable O, F, Ne, Na, Mg, Al, Si, S, Cl and Ar abundances. Results are presented in tabular form for each adopted nova simulation.

Christian Iliadis; Art Champagne; Jordi Jose; Sumner Starrfield; Paul Tupper

2002-06-03T23:59:59.000Z

265

Comparison and validation of HEU and LEU modeling results to HEU experimental benchmark data for the Massachusetts Institute of Technology MITR reactor.  

SciTech Connect (OSTI)

The Massachusetts Institute of Technology Reactor (MITR-II) is a research reactor in Cambridge, Massachusetts designed primarily for experiments using neutron beam and in-core irradiation facilities. It delivers a neutron flux comparable to current LWR power reactors in a compact 6 MW core using Highly Enriched Uranium (HEU) fuel. In the framework of its non-proliferation policies, the international community presently aims to minimize the amount of nuclear material available that could be used for nuclear weapons. In this geopolitical context, most research and test reactors both domestic and international have started a program of conversion to the use of Low Enriched Uranium (LEU) fuel. A new type of LEU fuel based on an alloy of uranium and molybdenum (UMo) is expected to allow the conversion of U.S. domestic high performance reactors like the MITR-II reactor. Towards this goal, comparisons of MCNP5 Monte Carlo neutronic modeling results for HEU and LEU cores have been performed. Validation of the model has been based upon comparison to HEU experimental benchmark data for the MITR-II. The objective of this work was to demonstrate a model which could represent the experimental HEU data, and therefore could provide a basis to demonstrate LEU core performance. This report presents an overview of MITR-II model geometry and material definitions which have been verified, and updated as required during the course of validation to represent the specifications of the MITR-II reactor. Results of calculations are presented for comparisons to historical HEU start-up data from 1975-1976, and to other experimental benchmark data available for the MITR-II Reactor through 2009. This report also presents results of steady state neutronic analysis of an all-fresh LEU fueled core. Where possible, HEU and LEU calculations were performed for conditions equivalent to HEU experiments, which serves as a starting point for safety analyses for conversion of MITR-II from the use of HEU fuel to the use of UMo LEU fuel.

Newton, T. H.; Wilson, E. H; Bergeron, A.; Horelik, N.; Stevens, J. (Nuclear Engineering Division); (MIT Nuclear Reactor Lab.)

2011-03-02T23:59:59.000Z

266

Strong plasma screening in thermonuclear reactions: Electron drop model  

E-Print Network [OSTI]

We analyze enhancement of thermonuclear fusion reactions due to strong plasma screening in dense matter using a simple electron drop model. The model assumes fusion in a potential that is screened by an effective electron cloud around colliding nuclei (extended Salpeter ion-sphere model). We calculate the mean field screened Coulomb potentials for atomic nuclei with equal and nonequal charges, appropriate astrophysical S factors, and enhancement factors of reaction rates. As a byproduct, we study analytic behavior of the screening potential at small separations between the reactants. In this model, astrophysical S factors depend not only on nuclear physics but on plasma screening as well. The enhancement factors are in good agreement with calculations by other methods. This allows us to formulate the combined, pure analytic model of strong plasma screening in thermonuclear reactions. The results can be useful for simulating nuclear burning in white dwarfs and neutron stars.

Kravchuk, P A

2014-01-01T23:59:59.000Z

267

Strong plasma screening in thermonuclear reactions: Electron drop model  

E-Print Network [OSTI]

We analyze enhancement of thermonuclear fusion reactions due to strong plasma screening in dense matter using a simple electron drop model. The model assumes fusion in a potential that is screened by an effective electron cloud around colliding nuclei (extended Salpeter ion-sphere model). We calculate the mean field screened Coulomb potentials for atomic nuclei with equal and nonequal charges, appropriate astrophysical S factors, and enhancement factors of reaction rates. As a byproduct, we study analytic behavior of the screening potential at small separations between the reactants. In this model, astrophysical S factors depend not only on nuclear physics but on plasma screening as well. The enhancement factors are in good agreement with calculations by other methods. This allows us to formulate the combined, pure analytic model of strong plasma screening in thermonuclear reactions. The results can be useful for simulating nuclear burning in white dwarfs and neutron stars.

P. A. Kravchuk; D. G. Yakovlev

2014-01-11T23:59:59.000Z

268

Relativistic outflow from two thermonuclear shell flashes on neutron stars  

E-Print Network [OSTI]

We study the exceptionally short (32-41 ms) precursors of two intermediate-duration thermonuclear X-ray bursts observed with RXTE from the neutron stars in 4U 0614+09 and 2S 0918-549. They exhibit photon fluxes that surpass those at the Eddington limit later in the burst by factors of 2.6 to 3.1. We are able to explain both the short duration and the super-Eddington flux by mildly relativistic outflow velocities of 0.1$c$ to 0.3$c$ subsequent to the thermonuclear shell flashes on the neutron stars. These are the highest velocities ever measured from any thermonuclear flash. The precursor rise times are also exceptionally short: about 1 ms. This is inconsistent with predictions for nuclear flames spreading laterally as deflagrations and suggests detonations instead. This is the first time that a detonation is suggested for such a shallow ignition column depth ($y_{\\rm ign}$ = 10$^{10}$ g cm$^{-2}$). The detonation would possibly require a faster nuclear reaction chain, such as bypassing the alpha-capture on $^...

Zand, Jean in 't; Cavecchi, Yuri

2014-01-01T23:59:59.000Z

269

Method of achieving the controlled release of thermonuclear energy  

DOE Patents [OSTI]

A method of achieving the controlled release of thermonuclear energy by illuminating a minute, solid density, hollow shell of a mixture of material such as deuterium and tritium with a high intensity, uniformly converging laser wave to effect an extremely rapid build-up of energy in inwardly traveling shock waves to implode the shell creating thermonuclear conditions causing a reaction of deuterons and tritons and a resultant high energy thermonuclear burn. Utilizing the resulting energy as a thermal source and to breed tritium or plutonium. The invention also contemplates a laser source wherein the flux level is increased with time to reduce the initial shock heating of fuel and provide maximum compression after implosion; and, in addition, computations and an equation are provided to enable the selection of a design having a high degree of stability and a dependable fusion performance by establishing a proper relationship between the laser energy input and the size and character of the selected material for the fusion capsule.

Brueckner, Keith A. (Ann Arbor, MI)

1986-01-01T23:59:59.000Z

270

English home Forum Photo Gallery Features Newsletter Archive About US Help Site Map languages Culture/Life  

E-Print Network [OSTI]

to build its own thermonuclear experimental reactor A leading Chinese plasma physicist said Thursday China might build its own thermonuclear experimental reactor, which would be expected to supply sustained in thermonuclear reaction, Chinese scientists have already participated in the International Thermonuclear

271

Brussels advocates a lone rider for ITER 09/22/2004 Edition  

E-Print Network [OSTI]

can advance alone to establish the thermonuclear reactor experimental ITER in Cadarache. France in the construction of the future experimental thermonuclear reactor ITER, if Brussels does not manage to convince

272

A meeting is planned Tuesday  

E-Print Network [OSTI]

Thermonuclear Experimental Reactor (ITER) -- a test bed for what is being billed as a safe and inexhaustible | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Google It: International Thermonuclear Spokesman Fabio Fabbi Questions Eu Optimism Experimental Reactor

273

EXTENSION OF THERMONUCLEAR FUNCTIONS THROUGH THE PATHWAY MODEL INCLUDING MAXWELL-BOLTZMANN AND TSALLIS DISTRIBUTIONS  

E-Print Network [OSTI]

Abstract. The Maxwell-Boltzmannian approach to nuclear reaction rate theory is extended to cover Tsallis statistics (Tsallis, 1988) and more general cases of distribution functions. An analytical study of respective thermonuclear functions is being conducted with the help of statistical techniques. The pathway model, recently introduced by Mathai (2005), is utilized for thermonuclear functions and closed-form representations are obtained in terms of H-functions and G-functions. Maxwell-Boltzmannian thermonuclear functions become particular cases of the extended thermonuclear functions. A brief review on the development of the theory of analytic representations of nuclear reaction rates is given. 1

H. J. Haubold

274

Extension of thermonuclear functions through the pathway model including Maxwell-Boltzmann and Tsallis distributions  

E-Print Network [OSTI]

The Maxwell-Boltzmannian approach to nuclear reaction rate theory is extended to cover Tsallis statistics (Tsallis, 1988) and more general cases of distribution functions. An analytical study of respective thermonuclear functions is being conducted with the help of statistical techniques. The pathway model, recently introduced by Mathai (2005), is utilized for thermonuclear functions and closed-form representations are obtained in terms of H-functions and G-functions. Maxwell-Boltzmannian thermonuclear functions become particular cases of the extended thermonuclear functions. A brief review on the development of the theory of analytic representations of nuclear reaction rates is given.

H. J. Haubold; D. Kumar

2007-08-16T23:59:59.000Z

275

Optical Spectra of Thermonuclear Supernovae in the Local and Distant Universe.  

E-Print Network [OSTI]

??This thesis is devoted to the study of optical spectra of thermonuclear supernovae, known as ``Type Ia'' supernovae (SN Ia). These violent stellar explosions, visible… (more)

Blondin, Stephane

2005-01-01T23:59:59.000Z

276

E-Print Network 3.0 - advanced fusion material Sample Search...  

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

Physics and Fusion 5 Fusion Energy Program Presentation to Summary: International Thermonuclear Experimental Reactor Plasma Technologies Fusion Technologies Advanced Materials......

277

U.S. Department of Energy Office of Inspector General Annual...  

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

Carbon Fiber Technology Center The Department of Energy's International Thermonuclear Experimental Reactor (ITER) Responsibilities Depleted Uranium Operations at...

278

E-Print Network 3.0 - advanced tokamak plasmas Sample Search...  

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

Physics and Fusion 15 Fusion Energy Program Presentation to Summary: International Thermonuclear Experimental Reactor Plasma Technologies Fusion Technologies Advanced Materials......

279

E-Print Network 3.0 - advanced deuterium fusion Sample Search...  

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

Physics and Fusion 2 Fusion Energy Program Presentation to Summary: International Thermonuclear Experimental Reactor Plasma Technologies Fusion Technologies Advanced Materials......

280

E-Print Network 3.0 - advanced toroidal facility Sample Search...  

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

Advanced Toroidal Facility InternationalOther Total Confinement Systems... International Thermonuclear Experimental Reactor Plasma Technologies Fusion Technologies Advanced...

Note: This page contains sample records for the topic "thermonuclear experimental 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

Thermonuclear Explosions of Chandrasekhar-Mass White Dwarfs  

E-Print Network [OSTI]

We present a new way of modeling turbulent thermonuclear deflagration fronts in Chandrasekhar-mass white dwarfs, consisting of carbon and oxygen, undergoing a type Ia supernova explosion. Our approach is a front capturing/tracking hybrid scheme, based on a level set method, which treats the front as a mathematical discontinuity and allows for full coupling between the front geometry and the flow field. First results of the method applied to the problem of type Ia supernovae are discussed. It will be shown that even in 2-D and even with a physically motivated sub-grid model numerically ``converged'' results are difficult to obtain.

W. Hillebrandt; M. Reinecke; J. C. Niemeyer

2000-05-16T23:59:59.000Z

282

Influence of gas composition on wafer temperature in a tungsten chemical vapor deposition reactor: Experimental measurements, model  

E-Print Network [OSTI]

Influence of gas composition on wafer temperature in a tungsten chemical vapor deposition reactor-wafer, lamp-heated chemical vapor deposition system were used to study the wafer temperature response to gas composition. A physically based simulation procedure for the process gas and wafer temperature was developed

Rubloff, Gary W.

283

Accepted Manuscript Making Tungsten Work  

E-Print Network [OSTI]

Thermonuclear Experimental Reactor Organization, Cadarache, FRANCE 3 Plasma Science and Fusion Center at MIT International Thermonuclear Experimental Reactor Organization, Cadarache, FRANCE 3 Plasma Science and Fusion Thermonuclear Experimental Reactor). Tungsten (W) is the plasma-facing material of choice in several design

Raffray, A. René

284

On the thermonuclear runaway in Type Ia supernovae: How to run away  

E-Print Network [OSTI]

Type Ia Supernovae are thought to be thermonuclear explosions of massive white dwarfs (WD). We present the first study of multi-dimensional effects during the final hours prior to the thermonuclear runaway which leads to the explosion. The calculations utilize an implicit, 2-D hydrodynamical code

P. Höflich; J. Stein

2002-01-01T23:59:59.000Z

285

Astrophysical Thermonuclear Functions for Boltzmann-Gibbs Statistics and Tsallis Statistics  

E-Print Network [OSTI]

We present an analytic proof of the integrals for astrophysical thermonuclear functions which are derived on the basis of Boltzmann-Gibbs statistical mechanics. Among the four different cases of astrophysical thermonuclear functions, those with a depleted high-energy tail and a cut-off at high energies find a natural interpretation in q-statistics.

R. K. Saxena; A. M. Mathai; H. J. Haubold

2004-06-22T23:59:59.000Z

286

Simulations of Turbulent Thermonuclear Burning in Type Ia Supernovae  

E-Print Network [OSTI]

Type Ia supernovae have recently received considerable attention because it appears that they can be used as "standard candles" to measure cosmic distances out to billions of light years away from us. Observations of type Ia supernovae seem to indicate that we are living in a universe that started to accelerate its expansion when it was about half its present age. These conclusions rest primarily on phenomenological models which, however, lack proper theoretical understanding, mainly because the explosion process, initiated by thermonuclear fusion of carbon and oxygen into heavier elements, is difficult to simulate even on supercomputers. Here, we investigate a new way of modeling turbulent thermonuclear deflagration fronts in white dwarfs undergoing a type Ia supernova explosion. Our approach is based on a level set method which treats the front as a mathematical discontinuity and allows for full coupling between the front geometry and the flow field. New results of the method applied to the problem of type Ia supernovae are obtained. It is shown that in 2-D with high spatial resolution and a physically motivated subgrid scale model for the nuclear flames numerically "converged" results can be obtained, but for most initial conditions the stars do not explode. In contrast, simulations in 3-D, do give the desired explosions and many of their properties, such as the explosion energies, lightcurves and nucleosynthesis products, are in very good agreement with observed type Ia supernovae.

W. Hillebrandt; M. Reinecke; W. Schmidt; F. K. Roepke; C. Travaglio; J. C. Niemeyer

2004-05-11T23:59:59.000Z

287

Cosmic and Galactic Neutrino Backgrounds from Thermonuclear Sources  

E-Print Network [OSTI]

We estimate energy spectra and fluxes at the Earth's surface of the cosmic and Galactic neutrino backgrounds produced by thermonuclear reactions in stars. The extra-galactic component is obtained by combining the most recent estimates of the cosmic star formation history and the stellar initial mass function with accurate theoretical predictions of the neutrino yields all over the thermonuclear lifetime of stars of different masses. Models of the structure and evolution of the Milky Way are used to derive maps of the expected flux generated by Galactic sources as a function of sky direction. The predicted neutrino backgrounds depend only slightly on model parameters. In the relevant 50 keV-10 MeV window, the total flux of cosmic neutrinos ranges between 20 and 65 particles per square cm per s. Neutrinos reaching the Earth today have been typically emitted at redshift z~2. Their energy spectrum peaks at E~0.1-0.3 MeV. The energy and entropy densities of the cosmic background are negligible with respect to the thermal contribution of relic neutrinos originated in the early universe. In every sky direction, the cosmic background is outnumbered by the Galactic one, whose integrated flux amounts to 300-1000 particles per square cm per s. The emission from stars in the Galactic disk contributes more than 95 per cent of the signal.

Cristiano Porciani; Silvia Petroni; Giovanni Fiorentini

2003-11-20T23:59:59.000Z

288

Faint Thermonuclear Supernovae from AM Canum Venaticorum Binaries  

E-Print Network [OSTI]

Helium that accretes onto a Carbon/Oxygen white dwarf in the double white dwarf AM Canum Venaticorum (AM CVn) binaries undergoes unstable thermonuclear flashes when the orbital period is in the 3.5-25 minute range. At the shortest orbital periods (and highest accretion rates, Mdot > 10^-7 Msol/yr), the flashes are weak and likely lead to the Helium equivalent of classical nova outbursts. However, as the orbit widens and Mdot drops, the mass required for the unstable ignition increases, leading to progressively more violent flashes up to a final flash with Helium shell mass ~ 0.02-0.1 Msol. The high pressures of these last flashes allow the burning to produce the radioactive elements 48Cr, 52Fe, and 56Ni that power a faint (M_V in the range of -15 to -18) and rapidly rising (few days) thermonuclear supernova. Current galactic AM CVn space densities imply one such explosion every 5,000-15,000 years in 10^11 Msol of old stars (~ 2-6% of the Type Ia rate in E/SO galaxies). These ".Ia" supernovae (one-tenth as bright for one-tenth the time as a Type Ia supernovae) are excellent targets for deep (e.g. V=24) searches with nightly cadences, potentially yielding an all-sky rate of 1,000 per year.

Lars Bildsten; Ken J. Shen; Nevin N. Weinberg; Gijs Nelemans

2007-05-06T23:59:59.000Z

289

Thermonuclear supernova models, and observations of Type Ia supernovae  

E-Print Network [OSTI]

In this paper, we review the present state of theoretical models of thermonuclear supernovae, and compare their predicitions with the constraints derived from observations of Type Ia supernovae. The diversity of explosion mechanisms usually found in one-dimensional simulations is a direct consequence of the impossibility to resolve the flame structure under the assumption of spherical symmetry. Spherically symmetric models have been successful in explaining many of the observational features of Type Ia supernovae, but they rely on two kinds of empirical models: one that describes the behaviour of the flame on the scales unresolved by the code, and another that takes account of the evolution of the flame shape. In contrast, three-dimensional simulations are able to compute the flame shape in a self-consistent way, but they still need a model for the propagation of the flame in the scales unresolved by the code. Furthermore, in three dimensions the number of degrees of freedom of the initial configuration of the white dwarf at runaway is much larger than in one dimension. Recent simulations have shown that the sensitivity of the explosion output to the initial conditions can be extremely large. New paradigms of thermonuclear supernovae have emerged from this situation, as the Pulsating Reverse Detonation. The resolution of all these issues must rely on the predictions of observational properties of the models, and their comparison with current Type Ia supernova data, including X-ray spectra of Type Ia supernova remnants.

E. Bravo; C. Badenes; D. Garcia-Senz

2004-12-07T23:59:59.000Z

290

On the Evolution of Thermonuclear Flames on Large Scales  

E-Print Network [OSTI]

The thermonuclear explosion of a massive white dwarf in a Type Ia supernova explosion is characterized by vastly disparate spatial and temporal scales. The extreme dynamic range inherent to the problem prevents the use of direct numerical simulation and forces modelers to resort to subgrid models to describe physical processes taking place on unresolved scales. We consider the evolution of a model thermonuclear flame in a constant gravitational field on a periodic domain. The gravitational acceleration is aligned with the overall direction of the flame propagation, making the flame surface subject to the Rayleigh-Taylor instability. The flame evolution is followed through an extended initial transient phase well into the steady-state regime. The properties of the evolution of flame surface are examined. We confirm the form of the governing equation of the evolution suggested by Khokhlov (1995). The mechanism of vorticity production and the interaction between vortices and the flame surface are discussed. The results of our investigation provide the bases for revising and extending previous subgrid-scale model.

Ju Zhang; O. E. Bronson Messer; Alexei M. Khokhlov; Tomasz Plewa

2006-10-05T23:59:59.000Z

291

A Systematic Approach to the Design of a Large Scale Detritiation System for Controlled Thermonuclear Fusion Experiments  

E-Print Network [OSTI]

A Systematic Approach to the Design of a Large Scale Detritiation System for Controlled Thermonuclear Fusion Experiments

292

Tidally-induced thermonuclear Supernovae Stephan Rosswog1, Enrico Ramirez-Ruiz2, W. Raphael Hix3  

E-Print Network [OSTI]

Tidally-induced thermonuclear Supernovae Stephan Rosswog1, Enrico Ramirez-Ruiz2, W. Raphael Hix3 1 in a thermonuclear explosion. These explosions are not restricted to progenitor masses close to the Chandrasekhar thermonuclear supernova together with an X-ray flare thus whistle-blows the existence of such moderate

Rosswog, Stephan

293

Thermonuclear rates of the 28Si(p, y) reaction M. Kicinska-Habior and T. Matulewicz  

E-Print Network [OSTI]

1881 Thermonuclear rates of the 28Si(p, y) reaction M. Kicinska-Habior and T. Matulewicz Institute Thermonuclear reaction rates NA av > are the quan- tities of essential importance for models of stellar in a much more extended energy range. The thermonuclear rates of the 28Si(p, y) reaction, although it does

Paris-Sud XI, Université de

294

An experimental system for the n-butyl-lithium initiated polymerization of styrene in a multi-sampled batch reactor  

E-Print Network [OSTI]

. The power to the water heater is controlled by a Fisher Proportional Temperature Control (Catalog P3 TENPERATURE CONTROLLER CONSTANT TENPERATURE BATH P2 CHILLER ELECTRICAL HEATER Figure 3. Schematic of Reactor Temperature Control System 20... successful column; i, e, , extremely high pressure drops and low plate counts were observed in these columns. As a last measure, the gel was stirred in a hot, concen- trated sodium hydroxide solution (approximately pH 13) for ten hours. The excess sodium...

Cox, James Harvey

2012-06-07T23:59:59.000Z

295

State of Advancement of the International REVE Project: Computational Modelling of Irradiation-Induced Hardening in Reactor Pressure Vessel Steels and Relevant Experimental Validation Programme  

SciTech Connect (OSTI)

The REVE (Reactor for Virtual Experiments) project is an international joint effort aimed at developing multi-scale modelling computational toolboxes capable of simulating the behaviour of materials under irradiation at different time and length scales. Well grounded numerical techniques such as molecular dynamics (MD) and Monte Carlo (MC) algorithms, as well as rate equation (RE) and dislocation-defect interaction theory, form the basis on which the project is built. The goal is to put together a suite of integrated codes capable of deducing the changes in macroscopic properties starting from a detailed simulation of the microstructural changes produced by irradiation in materials. To achieve this objective, several European laboratories are closely collaborating, while exchanging data with American and Japanese laboratories currently pursuing similar approaches. The material chosen for the first phase of this project is reactor pressure vessel (RPV) steel, the target macroscopic magnitude to be predicted being the yield strength increase ({delta}{sigma}y) due, essentially, to irradiation-enhanced formation of intragranular solute atom precipitates or clouds, as well as irradiation induced defects in the matrix, such as point defect clusters and dislocation loops. A description of the methodological approach used in the project and its current state is given in the paper. The development of the simulation tools requires a continuous feedback from ad hoc experimental data. In the framework of the REVE project SCK EN has therefore performed a neutron irradiation campaign of model alloys of growing complexity (from pure Fe to binary and ternary systems and a real RPV steel) in the Belgian test reactor BR2 and is currently carrying on the subsequent materials characterisation using its hot cell facilities. The paper gives the details of this experimental programme - probably the first large-scale one devoted to the validation of numerical simulation tools - and presents and discusses the first available results, with a view to their use as feedback for the improvement of the computational modelling. (authors)

Malerba, Lorenzo; Van Walle, Eric [SCK.CEN, Boeretang 200, 2400 Mol (Belgium); Domain, Christophe; Jumel, Stephanie; Van Duysen, Jean-Claude [EDR R and D (France)

2002-07-01T23:59:59.000Z

296

Composite Materials under Extreme Radiation and Temperature Environments of the Next Generation Nuclear Reactors  

SciTech Connect (OSTI)

In the nuclear energy renaissance, driven by fission reactor concepts utilizing very high temperatures and fast neutron spectra, materials with enhanced performance that exceeds are expected to play a central role. With the operating temperatures of the Generation III reactors bringing the classical reactor materials close to their performance limits there is an urgent need to develop and qualify new alloys and composites. Efforts have been focused on the intricate relations and the high demands placed on materials at the anticipated extreme states within the next generation fusion and fission reactors which combine high radiation fluxes, elevated temperatures and aggressive environments. While nuclear reactors have been in operation for several decades, the structural materials associated with the next generation options need to endure much higher temperatures (1200 C), higher neutron doses (tens of displacements per atom, dpa), and extremely corrosive environments, which are beyond the experience on materials accumulated to-date. The most important consideration is the performance and reliability of structural materials for both in-core and out-of-core functions. While there exists a great body of nuclear materials research and operating experience/performance from fission reactors where epithermal and thermal neutrons interact with materials and alter their physio-mechanical properties, a process that is well understood by now, there are no operating or even experimental facilities that will facilitate the extreme conditions of flux and temperature anticipated and thus provide insights into the behaviour of these well understood materials. Materials, however, still need to be developed and their interaction and damage potential or lifetime to be quantified for the next generation nuclear energy. Based on material development advances, composites, and in particular ceramic composites, seem to inherently possess properties suitable for key functions within the operating envelope of both fission and fusion reactors. In advanced fission reactors composite materials are being designed in an effort to extend the life and improve the reliability of fuel rod cladding as well as structural materials. Composites are being considered for use as core internals in the next generation of gas-cooled reactors. Further, next-generation plasma-fusion reactors, such as the International Thermonuclear Experimental Reactor (ITER) will rely on the capabilities of advanced composites to safely withstand extremely high neutron fluxes while providing superior thermal shock resistance.

Simos, N.

2011-05-01T23:59:59.000Z

297

Alerting Humanitarians to Emergencies TOKYO, March 9 (Reuters) -Japan warned the European Union on Wednesday  

E-Print Network [OSTI]

to construct the first thermonuclear reactor -- the European Union, Japan, China, the United States, Russia Thermonuclear Experimental Reactor (ITER) is forecast to cost some 4.6 billion euros ($6.14 billion) over 10

298

Energy limits on runaway electrons in tokamak plasmas J. R. Martin-Solisa)  

E-Print Network [OSTI]

runaway electrons in JET and the projected International Thermonuclear Experimental Reactor ITER ITER EDA International Thermonuclear Experi- mental Reactor ITER 1 where larger amounts of runaway electrons than those

Martín-Solís, José Ramón

299

Thermonuclear Explosions of Chandrasekhar-Mass White Dwarfs  

E-Print Network [OSTI]

We present a new way of modeling turbulent thermonuclear deflagration fronts in Chandrasekhar-mass white dwarfs, consisting of carbon and oxygen, undergoing a type Ia supernova explosion. Our approach is a front capturing/tracking hybrid scheme, based on a level set method, which treats the front as a mathematical discontinuity and allows for full coupling between the front geometry and the flow field. First results of the method applied to the problem of type Ia supernovae are discussed. It will be shown that even in 2-D and even with a physically motivated sub-grid model numerically “converged ” results are difficult to obtain. Key Words: Hydrodynamics, turbulent combustion, type Ia supernovae 1.

Thermonuclear Explosions; Wolfgang Hillebr; Martin Reinecke; Jens C. Niemeyer

2000-01-01T23:59:59.000Z

300

Screening in Thermonuclear Reaction Rates in the Sun  

E-Print Network [OSTI]

We evaluate the effect of electrostatic screening by ions and electrons on low-Z thermonuclear reactions in the sun. We use a mean field formalism and calculate the electron density of the screening cloud using the appropriate density matrix equation of quantum statistical mechanics. Because of well understood physical effects that are included for the first time in our treatment, the calculated enhancement of reaction rates does not agree with the frequently used interpolation formulae. Our result does agree, within small uncertainties, with Salpeter's weak screening formula. If weak screening is used instead of the commonly employed screening prescription of Graboske et al., the predicted $^8$B neutrino flux is increased by 7% and the predicted chlorine rate is increased by 0.4 SNU.

Andrei V. Gruzinov; John N. Bahcall

1998-01-20T23:59:59.000Z

Note: This page contains sample records for the topic "thermonuclear experimental 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

The Periods Discovered by RXTE in Thermonuclear Flash Bursts  

E-Print Network [OSTI]

Oscillations in the X-ray flux of thermonuclear X-ray bursts have been observed with RXTE from at least 6 low-mass binaries, at frequencies from 330 Hz to 589 Hz. There appear to be preferred relations between the frequencies present during the bursts and those seen in the persistent flux. The amplitude of the oscillations can exceed 50 % near burst onset. Except for a systematic increase in oscillation frequency as the burst progresses, the frequency is stable. Time resolved spectra track increases in the X-ray emitting area due to propagation of the burning front over the neutron star surface, as well as radiation driven expansion of the photosphere. The neutron star mass, radius, and distance can be inferred when spectra are compared to theoretical expectations.

T. E. Strohmayer; J. H. Swank; W. Zhang

1998-01-23T23:59:59.000Z

302

On the stability of thermonuclear shell sources in stars  

E-Print Network [OSTI]

We present a quantitative criterion for the thermal stability of thermonuclear shell sources. We find the thermal stability of shell sources to depend on exactly three factors: they are more stable when they are geometrically thicker, less degenerate and hotter. This confirms and unifies previously obtained results in terms of the geometry, temperature and density of the shell source, by a simplified but quantitative approach to the physics of shell nuclear burning. We present instability diagrams in the temperature-density plane for hydrogen and helium shell burning, which allow a simple evaluation of the stability conditions of such shell sources in stellar models. The performance of our stability criterion is demonstrated in various numerical models: in a 3 Msun AGB star, in helium accreting CO white dwarfs, in a helium white dwarf which is covered by a thin hydrogen envelope, and in a 1.0 Msun giant.

S. -C. Yoon; N. Langer; M. van der Sluys

2004-06-07T23:59:59.000Z

303

Repair welding of fusion reactor components. Final technical report  

SciTech Connect (OSTI)

The exposure of metallic materials, such as structural components of the first wall and blanket of a fusion reactor, to neutron irradiation will induce changes in both the material composition and microstructure. Along with these changes can come a corresponding deterioration in mechanical properties resulting in premature failure. It is, therefore, essential to expect that the repair and replacement of the degraded components will be necessary. Such repairs may require the joining of irradiated materials through the use of fusion welding processes. The present ITER (International Thermonuclear Experimental Reactor) conceptual design is anticipated to have about 5 km of longitudinal welds and ten thousand pipe butt welds in the blanket structure. A recent study by Buende et al. predict that a failure is most likely to occur in a weld. The study is based on data from other large structures, particularly nuclear reactors. The data used also appear to be consistent with the operating experience of the Fast Flux Test Facility (FFTF). This reactor has a fuel pin area comparable with the area of the ITER first wall and has experienced one unanticipated fuel pin failure after two years of operation. The repair of irradiated structures using fusion welding will be difficult due to the entrapped helium. Due to its extremely low solubility in metals, helium will diffuse and agglomerate to form helium bubbles after being trapped at point defects, dislocations, and grain boundaries. Welding of neutron-irradiated type 304 stainless steels has been reported with varying degree of heat-affected zone cracking (HAZ). The objectives of this study were to determine the threshold helium concentrations required to cause HAZ cracking and to investigate techniques that might be used to eliminate the HAZ cracking in welding of helium-containing materials.

Chin, B.A.; Wang, C.A.

1997-09-30T23:59:59.000Z

304

Measurement of neutron capture on 50Ti at thermonuclear energies  

E-Print Network [OSTI]

At the Karlsruhe and Tuebingen 3.75 MV Van de Graaff accelerators the thermonuclear 50Ti(n,gamma)51Ti(5.8 min) cross section was measured by the fast cyclic activation technique via the 320.852 and 928.65 keV gamma-ray lines of the 51Ti-decay. Metallic Ti samples of natural isotopic composition and samples of TiO2 enriched in 50Ti by 67.53 % were irradiated between two gold foils which served as capture standards. The capture cross-section was measured at the neutron energies 25, 30, 52, and 145 keV, respectively. The direct capture cross section was determined to be 0.387 +/- 0.011 mbarn at 30 keV. We found evidence for a bound state s-wave resonance with an estimated radiative width of 0.34 eV which destructively interfers with direct capture. The strength of a suggested s-wave resonance at 146.8 keV was determined. The present data served to calculate, in addition to the directly measured Maxwellian averaged capture cross sections at 25 and 52 keV, an improved stellar 50Ti(n,gamma)51Ti rate in the thermonuclear energy region from 1 to 250 keV. The new stellar rate leads at low temperatures to much higher values than the previously recommended rate, e.g., at kT=8 keV the increase amounts to about 50 %. The new reaction rate therefore reduces the abundance of 50Ti due to s-processing in AGB stars.

P. V. Sedyshev; P. Mohr; H. Beer; H. Oberhummer; Yu. P. Popov; W. Rochow

1999-07-28T23:59:59.000Z

305

Detonating Failed Deflagration Model of Thermonuclear Supernovae I. Explosion Dynamics  

E-Print Network [OSTI]

We present a detonating failed deflagration model of Type Ia supernovae. In this model, the thermonuclear explosion of a massive white dwarf follows an off-center deflagration. We conduct a survey of asymmetric ignition configurations initiated at various distances from the stellar center. In all cases studied, we find that only a small amount of stellar fuel is consumed during deflagration phase, no explosion is obtained, and the released energy is mostly wasted on expanding the progenitor. Products of the failed deflagration quickly reach the stellar surface, polluting and strongly disturbing it. These disturbances eventually evolve into small and isolated shock-dominated regions which are rich in fuel. We consider these regions as seeds capable of forming self-sustained detonations that, ultimately, result in the thermonuclear supernova explosion. Preliminary nucleosynthesis results indicate the model supernova ejecta are typically composed of about 0.1-0.25 Msun of silicon group elements, 0.9-1.2 Msun of iron group elements, and are essentially carbon-free. The ejecta have a composite morphology, are chemically stratified, and display a modest amount of intrinsic asymmetry. The innermost layers are slightly egg-shaped with the axis ratio ~1.2-1.3 and dominated by the products of silicon burning. This central region is surrounded by a shell of silicon-group elements. The outermost layers of ejecta are highly inhomogeneous and contain products of incomplete oxygen burning with only small admixture of unburned stellar material. The explosion energies are ~1.3-1.5 10^51 erg.

Tomasz Plewa

2006-11-24T23:59:59.000Z

306

Design of an experimental loop for post-LOCA heat transfer regimes in a Gas-cooled Fast Reactor  

E-Print Network [OSTI]

The goal of this thesis is to design an experimental thermal-hydraulic loop capable of generating accurate, reliable data in various convection heat transfer regimes for use in the formulation of a comprehensive convection ...

Cochran, Peter A. (Peter Andrew)

2005-01-01T23:59:59.000Z

307

11/21/2006 07:40 AMITAR-TASS Page 1 of 2http://www.itar-tass.com/eng/prnt.html?NewsID=11003725  

E-Print Network [OSTI]

by means of thermonuclear fusion at new power plants. The total cost of the project, in which approximately thermonuclear experimental reactor (ITER) was signed at the Elysee Palace here on Tuesday. Representatives the thermonuclear synthesis and had carried out a broad range of experimental works on "Tokamak" thermonuclear

308

Three-dimensional neutronics optimization of helium-cooled blanket for multi-functional experimental fusion-fission hybrid reactor (FDS-MFX)  

SciTech Connect (OSTI)

Three-dimensional neutronics optimization calculations were performed to analyse the parameters of Tritium Breeding Ratio (TBR) and maximum average Power Density (PDmax) in a helium-cooled multi-functional experimental fusion-fission hybrid reactor named FDS (Fusion-Driven hybrid System)-MFX (Multi-Functional experimental) blanket. Three-stage tests will be carried out successively, in which the tritium breeding blanket, uranium-fueled blanket and spent-fuel-fueled blanket will be utilized respectively. In this contribution, the most significant and main goal of the FDS-MFX blanket is to achieve the PDmax of about 100 MW/m3 with self-sustaining tritium (TBR {>=} 1.05) based on the second-stage test with uranium-fueled blanket to check and validate the demonstrator reactor blanket relevant technologies based on the viable fusion and fission technologies. Four different enriched uranium materials were taken into account to evaluate PDmax in subcritical blanket: (i) natural uranium, (ii) 3.2% enriched uranium, (iii) 19.75% enriched uranium, and (iv) 64.4% enriched uranium carbide. These calculations and analyses were performed using a home-developed code VisualBUS and Hybrid Evaluated Nuclear Data Library (HENDL). The results showed that the performance of the blanket loaded with 64.4% enriched uranium was the most attractive and it could be promising to effectively obtain tritium self-sufficiency (TBR-1.05) and a high maximum average power density ({approx}100 MW/m{sup 3}) when the blanket was loaded with the mass of {sup 235}U about 1 ton. (authors)

Jiang, J.; Yuan, B.; Jin, M.; Wang, M.; Long, P.; Hu, L. [Inst. of Nuclear Energy Safety Technology, Chinese Academy of Sciences, Univ. of Science and Technology of China, Hefei, Anhui, 230031 (China); School of Nuclear Science and Technology, Univ. of Science and Technology of China, No.350 Shushanhu Road, Shushan District, Hefei, Anhui, 230031 (China)

2012-07-01T23:59:59.000Z

309

A bright thermonuclear X-ray burst simultaneously observed with Chandra and RXTE  

E-Print Network [OSTI]

The prototypical accretion-powered millisecond pulsar SAX J1808.4?3658 was observed simultaneously with Chandra-LETGS and RXTE-PCA near the peak of a transient outburst in November 2011. A single thermonuclear (type-I) ...

in ’t Zand, J. J. M.

310

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

SciTech Connect (OSTI)

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

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

2006-10-20T23:59:59.000Z

311

DOEIEA-1108 ENVIRONMENTAL ASSESSMENT THE NATIONAL SPHERICAL TOKAMAK...  

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

as the existing Tokamak Fusion Test Reactor, TFTR, or the proposed International Thermonuclear Experimental Reactor, ITER) and operate at high plasma pressures, spherical...

312

Experimental Investigation of the Root Cause Mechanism and Effectiveness of Mitigating Actions for Axial Offset Anomaly in Pressurized Water Reactors  

SciTech Connect (OSTI)

Axial offset anomaly (AOA) in pressurized water reactors refers to the presence of a significantly larger measured negative axial offset deviation than predicted by core design calculations. The neutron flux depression in the upper half of high-power rods experiencing significant subcooled boiling is believed to be caused by the concentration of boron species within the crud layer formed on the cladding surface. Recent investigations of the root-cause mechanism for AOA [1,2] suggest that boron build-up on the fuel is caused by precipitation of lithium metaborate (LiBO2) within the crud in regions of subcooled boiling. Indirect evidence in support of this hypothesis was inferred from operating experience at Callaway, where lithium return and hide-out were, respectively, observed following power reductions and power increases when AOA was present. However, direct evidence of lithium metaborate precipitation within the crud has, heretofore, not been shown because of its retrograde solubility. To this end, this investigation has been undertaken in order to directly verify or refute the proposed root-cause mechanism of AOA, and examine the effectiveness of possible mitigating actions to limit its impact in high power PWR cores.

Said Abdel-Khalik

2005-07-02T23:59:59.000Z

313

Laser-fusion targets for reactors  

DOE Patents [OSTI]

A laser target comprising a thermonuclear fuel capsule composed of a centrally located quantity of fuel surrounded by at least one or more layers or shells of material for forming an atmosphere around the capsule by a low energy laser prepulse. The fuel may be formed as a solid core or hollow shell, and, under certain applications, a pusher-layer or shell is located intermediate the fuel and the atmosphere forming material. The fuel is ignited by symmetrical implosion via energy produced by a laser, or other energy sources such as an electron beam machine or ion beam machine, whereby thermonuclear burn of the fuel capsule creates energy for applications such as generation of electricity via a laser fusion reactor.

Nuckolls, John H. (Livermore, CA); Thiessen, Albert R. (Livermore, CA)

1987-01-01T23:59:59.000Z

314

Reaction Rate and Composition Dependence of the Stability of Thermonuclear Burning on Accreting Neutron Stars  

E-Print Network [OSTI]

The stability of thermonuclear burning of hydrogen and helium accreted onto neutron stars is strongly dependent on the mass accretion rate. The burning behavior is observed to change from Type I X-ray bursts to stable burning, with oscillatory burning occurring at the transition. Simulations predict the transition at a ten times higher mass accretion rate than observed. Using numerical models we investigate how the transition depends on the hydrogen, helium, and CNO mass fractions of the accreted material, as well as on the nuclear reaction rates of triple alpha and the hot-CNO breakout reactions 15O(a,g)19Ne and 18Ne(a,p)21Na. For a lower hydrogen content the transition is at higher accretion rates. Furthermore, most experimentally allowed reaction rate variations change the transition accretion rate by at most 10%. A factor ten decrease of the 15O(a,g)19Ne rate, however, produces an increase of the transition accretion rate of 35%. None of our models reproduce the transition at the observed rate, and depend...

Keek, L; Heger, A

2014-01-01T23:59:59.000Z

315

REVIEW OF EXPERIMENTAL CAPABILITIES AND HYDRODYNAMIC DATA FOR VALIDATION OF CFD BASED PREDICTIONS FOR SLURRY BUBBLE COLUMN REACTORS  

SciTech Connect (OSTI)

The purpose of this paper is to document the review of several open-literature sources of both experimental capabilities and published hydrodynamic data to aid in the validation of a Computational Fluid Dynamics (CFD) based model of a slurry bubble column (SBC). The review included searching the Web of Science, ISI Proceedings, and Inspec databases, internet searches as well as other open literature sources. The goal of this study was to identify available experimental facilities and relevant data. Integral (i.e., pertaining to the SBC system), as well as fundamental (i.e., separate effects are considered), data are included in the scope of this effort. The fundamental data is needed to validate the individual mechanistic models or closure laws used in a Computational Multiphase Fluid Dynamics (CMFD) simulation of a SBC. The fundamental data is generally focused on simple geometries (i.e., flow between parallel plates or cylindrical pipes) or custom-designed tests to focus on selected interfacial phenomena. Integral data covers the operation of a SBC as a system with coupled effects. This work highlights selected experimental capabilities and data for the purpose of SBC model validation, and is not meant to be an exhaustive summary.

Donna Post Guillen; Daniel S. Wendt

2007-11-01T23:59:59.000Z

316

REVIEW OF EXPERIMENTAL CAPABILITIES AND HYDRODYNAMIC DATA FOR VALIDATION OF CFD-BASED PREDICTIONS FOR SLURRY BUBBLE COLUMN REACTORS  

SciTech Connect (OSTI)

The purpose of this paper is to document the review of several open-literature sources of both experimental capabilities and published hydrodynamic data to aid in the validation of a Computational Fluid Dynamics (CFD) based model of a slurry bubble column (SBC). The review included searching the Web of Science, ISI Proceedings, and Inspec databases, internet searches as well as other open literature sources. The goal of this study was to identify available experimental facilities and relevant data. Integral (i.e., pertaining to the SBC system), as well as fundamental (i.e., separate effects are considered), data are included in the scope of this effort. The fundamental data is needed to validate the individual mechanistic models or closure laws used in a Computational Multiphase Fluid Dynamics (CMFD) simulation of a SBC. The fundamental data is generally focused on simple geometries (i.e., flow between parallel plates or cylindrical pipes) or custom-designed tests to focus on selected interfacial phenomena. Integral data covers the operation of a SBC as a system with coupled effects. This work highlights selected experimental capabilities and data for the purpose of SBC model validation, and is not meant to be an exhaustive summary.

Donna Post Guillen; Daniel S. Wendt; Steven P. Antal; Michael Z. Podowski

2007-11-01T23:59:59.000Z

317

Govt may concede ITER site to France The Yomiuri Shimbun  

E-Print Network [OSTI]

the building of the planned International Thermonuclear Experimental Reactor in another country providing Japan is an experimental facility of thermonuclear fusion, at which nuclear fusion reactions that occur on the sun

318

Thermonuclear X-ray Bursts: Theory vs. Observations  

E-Print Network [OSTI]

I review our theoretical understanding of thermonuclear flashes on accreting neutron stars, concentrating on comparisons to observations. Sequences of regular Type I X-ray bursts from GS 1826-24 and 4U 1820-30 are very well described by the theory. I discuss recent work which attempts to use the observed burst properties in these sources to constrain the composition of the accreted material. For GS 1826-24, variations in the burst energetics with accretion rate indicate that the accreted material has solar metallicity; for 4U 1820-30, future observations should constrain the hydrogen fraction, testing evolutionary models. I briefly discuss the global bursting behavior of burst sources, which continues to be a major puzzle. Finally, I turn to superbursts, which naturally fit into the picture as unstable carbon ignition in a thick layer of heavy elements. I present new time-dependent models of the cooling tails of superbursts, and discuss the various interactions between superbursts and normal Type I bursts, and what can be learned from them.

Andrew Cumming

2003-11-18T23:59:59.000Z

319

The NACRE Thermonuclear Reaction Compilation and Big Bang Nucleosynthesis  

E-Print Network [OSTI]

The theoretical predictions of big bang nucleosynthesis (BBN) are dominated by uncertainties in the input nuclear reaction cross sections. In this paper, we examine the impact on BBN of the recent compilation of nuclear data and thermonuclear reactions rates by the NACRE collaboration. We confirm that the adopted rates do not make large overall changes in central values of predictions, but do affect the magnitude of the uncertainties in these predictions. Therefore, we then examine in detail the uncertainties in the individual reaction rates considered by NACRE. When the error estimates by NACRE are treated as 1\\sigma limits, the resulting BBN error budget is similar to those of previous tabulations. We propose two new procedures for deriving reaction rate uncertainties from the nuclear data: one which sets lower limits to the error, and one which we believe is a reasonable description of the present error budget. We propagate these uncertainty estimates through the BBN code, and find that when the nuclear data errors are described most accurately, the resulting light element uncertainties are notably smaller than in some previous tabulations, but larger than others. Using these results, we derive limits on the cosmic baryon-to-photon ratio $\\eta$, and compare this to independent limits on $\\eta$ from recent balloon-borne measurements of the cosmic microwave background radiation (CMB). We discuss means to improve the BBN results via key nuclear reaction measurements and light element observations.

Richard H. Cyburt; Brian D. Fields; Keith A. Olive

2001-05-17T23:59:59.000Z

320

The cooling rate of neutron stars after thermonuclear shell flashes  

E-Print Network [OSTI]

Thermonuclear shell flashes on neutron stars are detected as bright X-ray bursts. Traditionally, their decay is modeled with an exponential function. However, this is not what theory predicts. The expected functional form for luminosities below the Eddington limit, at times when there is no significant nuclear burning, is a power law. We tested the exponential and power-law functional forms against the best data available: bursts measured with the high-throughput Proportional Counter Array (PCA) on board the Rossi X-ray Timing Explorer. We selected a sample of 35 'clean' and ordinary (i.e., shorter than a few minutes) bursts from 14 different neutron stars that 1) show a large dynamic range in luminosity, 2) are the least affected by disturbances by the accretion disk and 3) lack prolonged nuclear burning through the rp-process. We find indeed that for every burst a power law is a better description than an exponential function. We also find that the decay index is steep, 1.8 on average, and different for eve...

Zand, J J M in 't; Triemstra, T L; Mateijsen, R A D A; Bagnoli, T

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermonuclear experimental 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

The Sensitivity of Nucleosynthesis in Type I X-ray Bursts to Thermonuclear Reaction-Rate Variations  

E-Print Network [OSTI]

We examine the sensitivity of nucleosynthesis in Type I X-ray bursts to variations in nuclear rates. As a large number of nuclear processes are involved in these phenomena -with the vast majority of reaction rates only determined theoretically due to the lack of any experimental information- our results can provide a means for determining which rates play significant roles in the thermonuclear runaway. These results may then motivate new experiments. For our studies, we have performed a comprehensive series of one-zone post-processing calculations in conjunction with various representative X-ray burst thermodynamic histories. We present those reactions whose rate variations have the largest effects on yields in our studies.

Anuj Parikh; Jordi Jose; Fermin Moreno; Christian Iliadis

2008-06-18T23:59:59.000Z

322

If cheaper fusion reactors were developed, such as from compact toroids  

E-Print Network [OSTI]

FF (1984) Introduction to plasma physics and controlled thermonuclear fusion. Plenum, New York If cheaper fusion reactors were developed, such as from compact toroids If fusion­fission hybrids. Freidberg J (2006) Plasma physics and fusion energy. Cambridge University Press, Cambridge 3. "All

Deinert, Mark

323

Astrophysical S-factors of proton radiative capture for thermonuclear reactions  

E-Print Network [OSTI]

In this review we have considered the possibility to describe the astrophysical S-factors of radiative capture reactions with light atomic nuclei on the basis of the potential two-cluster model by taking into account the splitting the orbital states according to Young's schemes. Within this model, interaction of the nucleon clusters is described by local two-particle potential determined by fit to the scattering data and properties of bound states of these clusters. Many-body character of the problem is taken into account under some approximation, in terms of the allowed or forbidden by the Pauli principle states in intercluster potentials. An important feature of the approach is accounting for a dependence of interaction potential between clusters on the orbital Young scheme, which determines the permutation symmetry of the nucleon system. The astrophysical S-factors of the radiative capture processes in the p2H, p7Li and p12C systems are analyzed on the basis of this approach. It is shown that the approach allows one to describe quite reasonably experimental data available at low energies, when the phase shifts of cluster-cluster scattering are extracted from the data with minimal errors. In this connection the problem of experimental error decrease is exclusively urgent for the differential cross-sections of elastic scattering of light atomic nuclei at astrophysical energies and to perform a more accurate phase shift analysis. The increase in the accuracy will allow, in future, making more definite conclusions regarding the mechanisms and conditions of thermonuclear reactions, as well as understanding better their nature in general.

S. B. Dubovichenko; A. V. Dzhazairov-Kakhramanov

2011-12-09T23:59:59.000Z

324

The Fast-spectrum Transmutation Experimental Facility FASTEF: Main design achievements (part 2: Reactor building design and plant layout) within the FP7-CDT collaborative project of the European Commission  

SciTech Connect (OSTI)

MYRRHA (Multi-purpose hybrid Research Reactor for High-tech Applications) is the flexible experimental accelerator-driven system (ADS) in development at SCK-CEN in replacement of its material testing reactor BR2. SCK-CEN in association with 17 European partners from industry, research centres and academia, responded to the FP7 (Seventh Framework Programme) call from the European Commission to establish a Central Design Team (CDT) for the design of a Fast Spectrum Transmutation Experimental Facility (FASTEF) able to demonstrate efficient transmutation and associated technology through a system working in subcritical and/or critical mode. The project has started on April 01, 2009 for a period of three years. In this paper, we present the latest concept of the reactor building and the plant layout. The FASTEF facility has evolved quite a lot since the intermediate reporting done at the ICAPP'10 and ICAPP'11 conferences 1,2. Many iterations have been performed to take into account the safety requirements. The present configuration enables an easy operation and maintenance of the facility, including the possibility to change large components of the reactor. In a companion paper 3, we present the latest configuration of the reactor core and primary system. (authors)

De Bruyn, D.; Engelen, J. [Belgian Nuclear Research Centre SCK CEN, Boeretang 200, 2400 Mol (Belgium); Ortega, A.; Aguado, M. P. [Empresarios Agrupados A.I.E., Magallanes 3, 28015 Madrid (Spain)

2012-07-01T23:59:59.000Z

325

Brussels, May 31, 2005 NOTES Basic 1  

E-Print Network [OSTI]

and the exploitation of an experimental thermonuclear reactor (ITER) and implementation of the calendar envisaged and the exploitation of an experimental thermonuclear reactor (ITER) and implementation of the calendar envisaged thermonuclear engine. Six parts take part in the negotiations: China, South Korea, the United States, Japan

326

Also on the agenda would be  

E-Print Network [OSTI]

the multi- billion dollar International Thermonuclear Experimental Reactor (ITER), one of the most exciting the multi-billion dollar International Thermonuclear Experimental Reactor (ITER), one of the most exciting International Thermonuclear French President Jacques Chirac Six Month World Exposition Beijing Tiananmen Square

327

Contents of ITER deal revealed The Yomiuri Shimbun (May 27, 2005, 4 am)  

E-Print Network [OSTI]

in thermonuclear fusion. The country also will supply 20 percent of workers to ITER facilities. The four other on the roles of host and non-hosting countries involved in the International Thermonuclear Experimental Reactor. The planned ITER is an experimental facility for a thermonuclear reactor designed to produce power by fusing

328

On the Stability of Thermonuclear Burning Fronts in Type Ia Supernovae  

E-Print Network [OSTI]

Summary. The propagation of cellularly stabilized thermonuclear flames is investigated by means of numerical simulations. In Type Ia supernova explosions the corresponding burning regime establishes at scales below the Gibson length. The cellular flame stabilization—which is a result of an interplay between the Landau-Darrieus instability and a nonlinear stabilization mechanism—is studied for the case of propagation into quiescent fuel as well as interaction with vortical fuel flows. Our simulations indicate that in thermonuclear supernova explosions stable cellular flames develop around the Gibson scale and that a deflagration-to-detonation transition is unlikely to be triggered from flame evolution effects here. 1

F. K. Röpke; W. Hillebr

2004-01-01T23:59:59.000Z

329

On the Stability of Thermonuclear Burning Fronts in Type Ia Supernovae  

E-Print Network [OSTI]

The propagation of cellularly stabilized thermonuclear flames is investigated by means of numerical simulations. In Type Ia supernova explosions the corresponding burning regime establishes at scales below the Gibson length. The cellular flame stabilization - which is a result of an interplay between the Landau-Darrieus instability and a nonlinear stabilization mechanism - is studied for the case of propagation into quiescent fuel as well as interaction with vortical fuel flows. Our simulations indicate that in thermonuclear supernova explosions stable cellular flames develop around the Gibson scale and that deflagration-to-detonation transition is unlikely to be triggered from flame evolution effects here.

F. K. Roepke; W. Hillebrandt

2004-04-26T23:59:59.000Z

330

Contrib. Plasma Phys. 53, No. 45, 397 405 (2013) / DOI 10.1002/ctpp.201200094 Electron screening effect on stellar thermonuclear fusion  

E-Print Network [OSTI]

effect on stellar thermonuclear fusion Alexander Y. Potekhin1,2 and Gilles Chabrier2,3 1 Ioffe Physical thermonuclear reactions for various stellar objects, namely in the liquid envelopes of neutron stars. In addition, we examine some recent unconventional theo- retical results on stellar thermonuclear fusions

331

PHYS 390 Lecture 20 -Reactions III -Thermonuclear processes 20 -1 2001 by David Boal, Simon Fraser University. All rights reserved; further resale or copying is strictly prohibited.  

E-Print Network [OSTI]

PHYS 390 Lecture 20 - Reactions III - Thermonuclear processes 20 - 1 © 2001 by David Boal, Simon - Reactions III - Thermonuclear processes What's Important: · energy-dependent cross sections · complete rate 20 - Reactions III - Thermonuclear processes 20 - 2 © 2001 by David Boal, Simon Fraser University

Boal, David

332

Mon. Not. R. Astron. Soc. 401, 26 (2010) doi:10.1111/j.1365-2966.2009.15632.x Systematic variation in the apparent burning area of thermonuclear  

E-Print Network [OSTI]

in the apparent burning area of thermonuclear bursts and its implication for neutron star radius measurement Sudip area during the decay portions of thermonuclear (type I) X-ray bursts. However, this apparent area are challenging. Thermonuclear bursts provide one of the very few promising methods to measure the neutron star

Miller, Cole

333

Physics design of a 100 keV acceleration grid system for the diagnostic neutral beam for international tokamak experimental reactor  

SciTech Connect (OSTI)

This paper describes the physics design of a 100 keV, 60 A H{sup -} accelerator for the diagnostic neutral beam (DNB) for international tokamak experimental reactor (ITER). The accelerator is a three grid system comprising of 1280 apertures, grouped in 16 groups with 80 apertures per beam group. Several computer codes have been used to optimize the design which follows the same philosophy as the ITER Design Description Document (DDD) 5.3 and the 1 MeV heating and current drive beam line [R. Hemsworth, H. Decamps, J. Graceffa, B. Schunke, M. Tanaka, M. Dremel, A. Tanga, H. P. L. De Esch, F. Geli, J. Milnes, T. Inoue, D. Marcuzzi, P. Sonato, and P. Zaccaria, Nucl. Fusion 49, 045006 (2009)]. The aperture shapes, intergrid distances, and the extractor voltage have been optimized to minimize the beamlet divergence. To suppress the acceleration of coextracted electrons, permanent magnets have been incorporated in the extraction grid, downstream of the cooling water channels. The electron power loads on the extractor and the grounded grids have been calculated assuming 1 coextracted electron per ion. The beamlet divergence is calculated to be 4 mrad. At present the design for the filter field of the RF based ion sources for ITER is not fixed, therefore a few configurations of the same have been considered. Their effect on the transmission of the electrons and beams through the accelerator has been studied. The OPERA-3D code has been used to estimate the aperture offset steering constant of the grounded grid and the extraction grid, the space charge interaction between the beamlets and the kerb design required to compensate for this interaction. All beamlets in the DNB must be focused to a single point in the duct, 20.665 m from the grounded grid, and the required geometrical aimings and aperture offsets have been calculated.

Singh, M. J. [ITER-India, Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428 (India); De Esch, H. P. L. [CEA-Cadarache, IRFM, F-13108 Saint-Paul-lez-Durance (France)

2010-01-15T23:59:59.000Z

334

Millihertz quasi-periodic oscillations and thermonuclear bursts from Terzan 5: A showcase of burning regimes  

E-Print Network [OSTI]

We present a comprehensive study of the thermonuclear bursts and millihertz quasi-periodic oscillations (mHz QPOs) from the neutron star (NS) transient and 11 Hz X-ray pulsar IGR J17480–2446, located in the globular cluster ...

Linares, M.

335

Complex workplace radiation fields at European high-energy accelerators and thermonuclear fusion facilities  

E-Print Network [OSTI]

This report outlines the research needs and research activities within Europe to develop new and improved methods and techniques for the characterization of complex radiation fields at workplaces around high-energy accelerators and the next generation of thermonuclear fusion facilities under the auspices of the COordinated Network for RAdiation Dosimetry (CONRAD) project funded by the European Commission.

Bilski, P; D'Errico, F; Esposito, A; Fehrenbacher, G; Fernàndez, F; Fuchs, A; Golnik, N; Lacoste, V; Leuschner, A; Sandri, S; Silari, M; Spurny, F; Wiegel, B; Wright, P

2006-01-01T23:59:59.000Z

336

Reactor Physics  

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

Reactor Physics Reactor and nuclear physics is a key area of research at INL. Much of the research done in reactor physics can be separated into one of three categories:...

337

Reactor Safety Research Programs  

SciTech Connect (OSTI)

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

Edler, S. K.

1981-07-01T23:59:59.000Z

338

Experimental Conclusions  

E-Print Network [OSTI]

temperature and high pressure pyrolysis of biomass performed at industrially relevant heating rates. (2-Pressure Biomass Pyrolysis in an Entrained-Flow Reactor 1Gautami Newalkar, 2Kristiina Iisa, 1Carsten Sievers and 1) Objective Results Experimental Conclusions 1000°C 600°C 4s 30s A major advantage of Biomass

Das, Suman

339

IOP PUBLISHING and INTERNATIONAL ATOMIC ENERGY AGENCY NUCLEAR FUSION Nucl. Fusion 50 (2010) 014003 (8pp) doi:10.1088/0029-5515/50/1/014003  

E-Print Network [OSTI]

the development of a thermonuclear reactor. Following this, experimental research on plasma initiation and heating participating at that time in the development of thermonuclear weapons at the then secret Arzamas-16 nuclear and performed the first estimations of a possible thermonuclear reactor with magnetic confinement of plasma

340

CONDENSATION IN EJECTA FROM DENSE THERMONUCLEAR SUPERNOVAE. T. Yu1, B. S. Meyer1, A. V. Fedkin2, and L. Grossman2,3, 1Department of Physics and Astronomy, Clemson University, Clemson, SC  

E-Print Network [OSTI]

CONDENSATION IN EJECTA FROM DENSE THERMONUCLEAR SUPERNOVAE. T. Yu1, B. S. Meyer1, A. V. Fedkin2 Thermonuclear Supernova Model: Thermonuclear (Type Ia) supernovae are explosions of white dwarf stars. Our model and then oxy- gen burning proceed under degenerate conditions, a thermonuclear runaway occurs, which leads

Grossman, Lawrence

Note: This page contains sample records for the topic "thermonuclear experimental 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

PLT scaling laws for thermonuclear fusion power multiplication  

SciTech Connect (OSTI)

While present experiments are evaluated on the basis of confinement time, it is the fusion power multiplication factor, Q, and the fusion power which will be the parameters that measure the performance of ignition experiments and fusion reactors. We have determined the relationship of Q to tau/sub E/ and the Lawson number, n tau/sub e/, for ohmically heated plasmas from the Princeton Large Tokamak (PLT). Q, tau/sub E/, and n tau/sub E/ all increase with density at low densities. Above anti n/sub e/ approx. = 4 x 10/sup 13/ cm/sup -3/, tau/sub Ee/ approx. = 30 msec, or anti n/sub e/ tau/sub Ee/ approx. = 1.5 x 10/sup 12/ cm/sup -3/s, Q saturates. Q scaling has also been obtained on PLT as a function of toroidal magnetic field, plasma current, and auxiliary heating power.

Grisham, L.R.; Strachan, J.D.

1982-11-01T23:59:59.000Z

342

THE FERMI-GBM X-RAY BURST MONITOR: THERMONUCLEAR BURSTS FROM 4U 0614+09  

E-Print Network [OSTI]

Thermonuclear bursts from slowly accreting neutron stars (NSs) have proven difficult to detect, yet they are potential probes of the thermal properties of the NS interior. During the first year of a systematic all-sky ...

Connaughton, V.

343

Charged-Particle Thermonuclear Reaction Rates: III. Nuclear Physics Input  

E-Print Network [OSTI]

The nuclear physics input used to compute the Monte Carlo reaction rates and probability density functions that are tabulated in the second paper of this series (Paper II) is presented. Specifically, we publish the input files to the Monte Carlo reaction rate code RatesMC, which is based on the formalism presented in the first paper of this series (Paper I). This data base contains overwhelmingly experimental nuclear physics information. The survey of literature for this review was concluded in November 2009.

Christian Iliadis; Richard Longland; Art Champagne; Alain Coc

2010-04-23T23:59:59.000Z

344

Oscillations During Thermonuclear X-ray Bursts: A New Probe of Neutron Stars  

E-Print Network [OSTI]

Observations of thermonuclear (Type I) X-ray bursts from neutron stars in low mass X-ray binaries (LMXB) with the Rossi X-ray Timing Explorer (RXTE) have revealed large amplitude, high coherence X-ray brightness oscillations with frequencies in the 300 - 600 Hz range. Substantial spectral and timing evidence point to rotational modulation of the X-ray burst flux as the cause of these oscillations, and it is likely that they reveal the spin frequencies of neutron stars in LMXB from which they are detected. Here I review the status of our knowledge of these oscillations and describe how they can be used to constrain the masses and radii of neutron stars as well as the physics of thermonuclear burning on accreting neutron stars.

Tod E. Strohmayer

1999-11-19T23:59:59.000Z

345

The variation of the fine structure constant: testing the dipole model with thermonuclear supernovae  

E-Print Network [OSTI]

The large-number hypothesis conjectures that fundamental constants may vary. Accordingly, the spacetime variation of fundamental constants has been an active subject of research for decades. Recently, using data obtained with large telescopes a phenomenological model in which the fine structure constant might vary spatially has been proposed. We test whether this hypothetical spatial variation of {\\alpha}, which follows a dipole law, is compatible with the data of distant thermonuclear supernovae. Unlike previous works, in our calculations we consider not only the variation of the luminosity distance when a varying {\\alpha} is adopted, but we also take into account the variation of the peak luminosity of Type Ia supernovae resulting from a variation of {\\alpha}. This is done using an empirical relation for the peak bolometric magnitude of thermonuclear supernovae that correctly reproduces the results of detailed numerical simulations. We find that there is no significant difference between the several phenome...

Kraiselburd, Lucila; Negrelli, Carolina; Berro, Enrique García

2014-01-01T23:59:59.000Z

346

Thermonuclear fusion in dense stars: Electron screening, conductive cooling, and magnetic field effects  

E-Print Network [OSTI]

We study the plasma correlation effects on nonresonant thermonuclear reactions of carbon and oxygen in the interiors of white dwarfs and liquid envelopes of neutron stars. We examine the effects of electron screening on thermodynamic enhancement of thermonuclear reactions in dense plasmas beyond the linear mixing rule. Using these improved enhancement factors, we calculate carbon and oxygen ignition curves in white dwarfs and neutron stars. The energy balance and ignition conditions in neutron star envelopes are evaluated, taking their detailed thermal structure into account. The result is compared to the simplified "one-zone model," which is routinely used in the literature. We also consider the effect of strong magnetic fields on the ignition curves in the ocean of magnetars.

Potekhin, A Y

2012-01-01T23:59:59.000Z

347

A Study and Comparison of SCR Reaction Kinetics from Reactor...  

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

Data A Study and Comparison of SCR Reaction Kinetics from Reactor and Engine Experimental Data Presents experimental study of a Cu-zeolite SCR in both reactor and engine test cell,...

348

A revised thermonuclear rate of $^{7}$Be($n$,$\\alpha$)$^{4}$He relevant to Big-Bang nucleosynthesis  

E-Print Network [OSTI]

In the standard Big-Bang nucleosynthesis (BBN) model, the primordial $^7$Li abundance is overestimated by about a factor of 2--3 comparing to the astronomical observations, so called the pending cosmological lithium problem. The $^7$Be($n$,$\\alpha$)$^4$He reaction, which may affect the $^7$Li abundance, was regarded as the secondary important reaction in destructing the $^7$Be nucleus in BBN. However, the thermonuclear rate of $^7$Be($n$,$\\alpha$)$^4$He has not been well studied so far. This reaction rate was firstly estimated by Wagoner in 1969, which has been generally adopted in the current BBN simulations and the reaction rate library. This simple estimation involved only a direct-capture reaction mechanism, but the resonant contribution should be also considered according to the later experimental results. In this work, we have revised this rate based on the indirect cross-section data available for the $^4$He($\\alpha$,$n$)$^7$Be and $^4$He($\\alpha$,$p$)$^7$Li reactions, with the charge symmetry and deta...

Hou, S Q; Kubono, S; Chen, Y S

2015-01-01T23:59:59.000Z

349

LIGHTCURVES OF THERMONUCLEAR SUPERNOVAE AS A PROBE OF THE EXPLOSION MECHANISM AND THEIR USE IN COSMOLOGY  

E-Print Network [OSTI]

Thermonuclear supernovae are valuable for cosmology but their physics is not yet fully understood. Modeling the development and propagation of nuclear flame is complicated by numerous instabilities. The predictions of supernova light curves still involve some simplifying assumptions, but one can use the comparison of the computed fluxes with observations to constrain the explosion mechanism. In spite of great progress in recent years, a number of issues remains unsolved both in flame physics and light curve modeling. 1

S. I. Blinnikov; E. I. Sorokina

2002-01-01T23:59:59.000Z

350

Hydrodynamic simulations of a combined hydrogen, helium thermonuclear runaway on a 10-km neutron star  

SciTech Connect (OSTI)

We have used a Lagrangian, hydrodynamic stellar-evolution computer code to evolve a thermonuclear runaway in the accreted hydrogen rich envelope of a 1.0M, 10-km neutron star. Our simulation produced an outburst which lasted about 2000 sec and peak effective temperature was 3 keV. The peak luminosity exceeded 2 x 10/sup 5/ L. A shock wave caused a precursor in the light curve which lasted 10/sup -5/ sec.

Starrfield, S.; Kenyon, S.; Truran, J.W.; Sparks, W.M.

1983-01-01T23:59:59.000Z

351

Lightcurves of thermonuclear supernovae as a probe of the explosion mechanism and their use in cosmology  

E-Print Network [OSTI]

Thermonuclear supernovae are valuable for cosmology but their physics is not yet fully understood. Modeling the development and propagation of nuclear flame is complicated by numerous instabilities. The predictions of supernova light curves still involve some simplifying assumptions, but one can use the comparison of the computed fluxes with observations to constrain the explosion mechanism. In spite of great progress in recent years, a number of issues remains unsolved both in flame physics and light curve modeling.

S. Blinnikov; E. Sorokina

2002-12-30T23:59:59.000Z

352

Thermonuclear Runaways on Accreting White Dwarfs: Models of Classical Novae Explosions  

E-Print Network [OSTI]

The mechanism of classical novae explosions is explained, together with some of their observational properties. The scarce but not null impact of novae in the chemical evolution of the Milky Way is analyzed, as well as their relevance for the radioactivity in the Galaxy. A special emphasis is given to the predicted gamma-ray emission from novae and its relationship with the thermonuclear model itself and its related nucleosynthesis.

Margarita Hernanz; Jordi Jose

2000-01-11T23:59:59.000Z

353

Application of a new screening model to thermonuclear reactions of the rp process  

E-Print Network [OSTI]

A new screening model for astrophysical thermonuclear reactions was derived recently which improved Salpeter's weak-screening one. In the present work we prove that the new model can also give very reliable screening enhancement factors (SEFs) when applied to the rp process. According to the results of the new model, which agree well with Mitler's SEFs, the screened rp reaction rates can be, at most, twice as fast as the unscreened ones.

Theodore Liolios

2003-05-09T23:59:59.000Z

354

Thermonuclear explosion of rotating massive stars could explain core-collapse supernovae  

E-Print Network [OSTI]

It is widely thought that core-collapse supernovae (CCSNe), the explosions of massive stars following the collapse of the stars' iron cores, is obtained due to energy deposition by neutrinos. So far, this scenario was not demonstrated from first principles. Kushnir and Katz (2014) have recently shown, by using one-dimensional simulations, that if the neutrinos failed to explode the star, a thermonuclear explosion of the outer shells is possible for some (tuned) initial profiles. However, the energy released was small and negligible amounts of ejected $^{56}$Ni were obtained, implying that these one-dimensional collapse induced thermonuclear explosions (CITE) are unlikely to represent typical CCSNe. Here I provide evidence supporting a scenario in which the majority of CCSNe are the result of CITE. I use two-dimensional simulations to show that collapse of stars that include slowly (few percent of breakup) rotating $\\sim0.1-10\\,M_{\\odot}$ shells of mixed helium-oxygen, leads to an ignition of a thermonuclear d...

Kushnir, Doron

2015-01-01T23:59:59.000Z

355

E-Print Network 3.0 - aomori prefecture japan Sample Search Results  

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

Help My Yahoo http:asia.news.yahoo.com041111kyodod869foe00.html Summary: Thermonuclear Experimental Reactor to Aomori Prefecture. "The Japanese business community should...

356

U.S. and China Announce Cooperation on FutureGen and Sign Energy...  

Energy Savers [EERE]

a Hydrogen Economy; the Carbon Sequestration Leadership Forum; the International Thermonuclear Experimental Reactor; and the Generation IV International Forum. Secretary Bodman...

357

Timeline of Events: 1991 to 2000 | Department of Energy  

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

European Union, and Japan that will end U. S. participation in the International Thermonuclear Experimental Reactor (ITER) project by July 1999. October 19, 1998 The Department...

358

E-Print Network 3.0 - aichi prefecture japan Sample Search Results  

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

National efforts urged to win ITER location in Japan Japan Business Federation... Thermonuclear Experimental Reactor to Aomori Prefecture. "The Japanese business community should...

359

--No Title--  

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

from national laboratories and universities. Leading the list was the International Thermonuclear Experimental Reactor, a facility capable of producing a "burning plasma" fusion...

360

A A S BA IMPORTANT ISSUES W BOOK TWO O  

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

environmental national security challenges. Section 3 - Science 3-1 International Thermonuclear Experimental Reactor (ITER) * ITER is a large-scale fusion energy research...

Note: This page contains sample records for the topic "thermonuclear experimental 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

E-Print Network 3.0 - advanced fusion concepts Sample Search...  

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

10.3 Alternate Concepts Fusion Technology FY 1995 -- 372.6 12;... International Thermonuclear Experimental Reactor Plasma Technologies Fusion Technologies Advanced Materials......

362

--No Title--  

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

joined Martin Marietta Energy Systems as project coordinator for the International Thermonuclear Experimental Reactor (ITER) engineering design activities. He became the U.S. ITER...

363

E-Print Network 3.0 - armoured actively cooled Sample Search...  

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

on the actively cooled plasma facing components (PFCs) of the International Thermonuclear Experimental Reactor... of the actively cooled component itself. These have...

364

MagLab - RET Blog 2013: Erin Smidt  

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

never heard about either. ITER (pronounced eater) is an acronym for International Thermonuclear Experimental Reactor. ITER is an international fusion project that sounds...

365

Reactor Safety Research Programs  

SciTech Connect (OSTI)

This document summarizes the work performed by Pacific Northwest laboratory from October 1 through December 31, 1979, for the Division of Reactor Safety Research within the Nuclear Regulatory Commission. Evaluation of nondestructive examination (NDE) techniques and instrumentation are reported; areas of investigation include demonstrating the feasibilty of determining structural graphite strength, evaluating the feasibilty of detecting and analyzing flaw growth in reactor pressure boundary systems, examining NDE reliability and probabilistic fracture mechanics, and assessing the remaining integrity of pressurized water reactor steam generator tubes where service-induced degradation has been indicated. Test assemblies and analytical support are being provided for experimental programs at other facilities. These programs include the loss-of-coolant accident simulation tests at the NRU reactor, Chalk River, Canada; the fuel rod deformation and post-accident coolability tests for the ESSOR Test Reactor Program, lspra, Italy; the blowdown and reflood tests in the test facility at Cadarache, France; the instrumented fuel assembly irradiation program at Halden, Norway; and the experimental programs at the Power Burst Facility, Idaho National Engineering Laboratory. These programs will provide data for computer modeling of reactor system and fuel performance during various abnormal operating conditions.

Dotson, CW

1980-08-01T23:59:59.000Z

366

PPPL-3171 -Preprint Date: May 1996, UC-421, 423, 427 Simulations of alpha particle ripple loss from the  

E-Print Network [OSTI]

Thermonuclear Experimental Reactor (ITER) [Plasma Physics and Controlled Nuclear Fusion Research (International from the International Thermonuclear Experimental Reactor M. H. Redi, R. V. Budny, D. C. McCune, C. O for D shaped ripple contours. In contrast to alpha loss simulations for the Tokamak Fusion Test Reactor

367

NUCLEAR MATERIALS RESEARCH PROGRESS REPORTS FROM 1977  

E-Print Network [OSTI]

Chemical Effects of Thermonuclear Plasma Interactions Withfor Controlled Thermonuclear Reactor (CTR), USAEC Report LA-

Olander, D.R.

2012-01-01T23:59:59.000Z

368

RECENT PROGRESS IN HEAVY ION SOURCES  

E-Print Network [OSTI]

beams of hydrogen into thermonuclear fusion reactors. Ain magnetic confinement thermonuclear devices, such as

Clark, D.J.

2010-01-01T23:59:59.000Z

369

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

E-Print Network [OSTI]

with nine pipes in the cavity, return and supply manifolds connecting standing pipes with water tank and a cylindrical water tank situated at top of the cavity (as shown in Figure 5). In the facility, the cylindrical reactor vessel is approximately... Simulation ......................................................................... 14 2.3.1 Water Tank as Single Volume Without Secondary Loop ............................. 14 2.3.2 Water Tank as Pipe with Secondary Loop...

Wu, Huali

2013-08-08T23:59:59.000Z

370

Interfacial effects in fast reactors  

E-Print Network [OSTI]

The problem of increased resonance capture rates near zone interfaces in fast reactor media has been examined both theoretically and experimentally. An interface traversing assembly was designed, constructed and employed ...

Saidi, Mohammad Said

1979-01-01T23:59:59.000Z

371

Reactor physics project final report  

E-Print Network [OSTI]

This is the final report in an experimental and theoretical program to develop and apply single- and few-element methods for the determination of reactor lattice parameters. The period covered by the report is January 1, ...

Driscoll, Michael J.

1970-01-01T23:59:59.000Z

372

Evidence for a New Path to the Self-Sustainment of the Thermonuclear Fusion Reactions in Magnetically Confined Burning Plasma Experiments  

E-Print Network [OSTI]

Evidence for a New Path to the Self-Sustainment of the Thermonuclear Fusion Reactions in Magnetically Confined Burning Plasma Experiments

373

Development of high-speed and wide-angle visible observation diagnostics on Experimental Advanced Superconducting Tokamak using catadioptric optics  

SciTech Connect (OSTI)

A new wide-angle endoscope for visible light observation on the Experimental Advanced Superconducting Tokamak (EAST) has been recently developed. The head section of the optical system is based on a mirror reflection design that is similar to the International Thermonuclear Experimental Reactor-like wide-angle observation diagnostic on the Joint European Torus. However, the optical system design has been simplified and improved. As a result, the global transmittance of the system is as high as 79.6% in the wavelength range from 380 to 780 nm, and the spatial resolution is <5 mm for the full depth of field (4000 mm). The optical system also has a large relative aperture (1:2.4) and can be applied in high-speed camera diagnostics. As an important diagnostic tool, the optical system has been installed on the HT-7 (Hefei Tokamak-7) for its final experimental campaign, and the experiments confirmed that it can be applied to the investigation of transient processes in plasma, such as ELMy eruptions in H-mode, on EAST.

Yang, J. H.; Hu, L. Q.; Zang, Q.; Han, X. F.; Shao, C. Q.; Sun, T. F.; Chen, H.; Wang, T. F.; Li, F. J.; Hu, A. L. [Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031 (China)] [Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031 (China); Yang, X. F. [Jiangsu Province Key Laboratory of Modern Optical Technology, Soochow University, Suzhou, Jiangsu 215006 (China)] [Jiangsu Province Key Laboratory of Modern Optical Technology, Soochow University, Suzhou, Jiangsu 215006 (China)

2013-08-15T23:59:59.000Z

374

On the thermonuclear runaway in Type Ia supernovae: How to run away  

E-Print Network [OSTI]

Type Ia Supernovae are thought to be thermonuclear explosions of massive white dwarfs (WD). We present the first study of multi-dimensional effects during the final hours prior to the thermonuclear runaway which leads to the explosion. The calculations utilize an implicit, 2-D hydrodynamical code. Mixing and the ignition process are studied in detail. We find that the initial chemical structure of the WD is changed but the material is not fully homogenized. In particular, the exploding WD sustains a central region with a low C/O ratio. This implies that the explosive nuclear burning will begin in a partially carbon-depleted environment. The thermonuclear runaway happens in a well defined region close to the center. It is induced by compressional heat when matter is brought inwards by convective flows. We find no evidence for multiple spot or strong off-center ignition. Convective velocities in the WD are of the order of 100 km/sec which is well above the effective burning speeds in SNe Ia previously expected right after the runaway. For ? 0.5 to 1 sec, the speed of the burning front will neither be determined by the laminar speed nor the Rayleigh-Taylor instabilities but by convective flows produced prior to the runaway. The consequences are discussed for our understanding of the detailed physics of the flame propagation, the deflagration detonation transition, and the nucleosynthesis in the central layers. Our results strongly suggest the pre-conditioning of the progenitor as a key factor for our understanding of the diversity in Type Ia Supernovae.

P. Höflich; J. Stein

2002-01-01T23:59:59.000Z

375

A Characterization of the Brightness Oscillations During Thermonuclear Bursts From 4U 1636-536  

E-Print Network [OSTI]

The discovery of nearly coherent brightness oscillations during thermonuclear X-ray bursts from six neutron-star low-mass X-ray binaries has opened up a new way to study the propagation of thermonuclear burning, and may ultimately lead to greater understanding of thermonuclear propagation in other astrophysical contexts, such as in Type Ia supernovae. Here we report detailed analyses of the ~580 Hz brightness oscillations during bursts from 4U 1636-536. We investigate the bursts as a whole and, in more detail, the initial portions of the bursts. We analyze the ~580 Hz oscillations in the initial 0.75 seconds of the five bursts that were used in a previous search for a brightness oscillation at the expected ~290 Hz spin frequency, and find that if the same frequency model describes all five bursts there is insufficient data to require more than a constant frequency or, possibly, a frequency plus a frequency derivative. Therefore, although it is appropriate to use an arbitrarily complicated model of the ~580 Hz oscillations to generate a candidate waveform for the ~290 Hz oscillations, models with more than two parameters are not required by the data. For the bursts as a whole we show that the characteristics of the brightness oscillations vary greatly from burst to burst. We find, however, that in at least one of the bursts, and possibly in three of the four that have strong brightness oscillations throughout the burst, the oscillation frequency reaches a maximum several seconds into the burst and then decreases. This behavior has not been reported previously for burst brightness oscillations, and it poses a challenge to the standard burning layer expansion explanation for the frequency changes.

M. Coleman Miller

1999-04-08T23:59:59.000Z

376

On the Thermonuclear Runaway in Type Ia Supernovae: How to run away?  

E-Print Network [OSTI]

Type Ia Supernovae are thought to be thermonuclear explosions of massive white dwarfs (WD). We present the first study of multi-dimensional effects during the final hours prior to the thermonuclear runaway which leads to the explosion. The calculations utilize an implicit, 2-D hydro code.Mixing and the ignition process are studied in detail. We find that the initial chemical structure of the WD is changed but the material is not fully homogenized. The exploding WD sustains a central region with a low C/O ratio. This implies that the explosive nuclear burning will begin in a partially C-depleted environment. The thermonuclear runaway happens in a well defined region close to the center. It is induced by compressional heat when matter is brought inwards by convective flows. We find no evidence for multiple spot or strong off-center ignition. Convective velocities are of the order of 100 km/sec which is well above the effective burning speeds in SNe Ia previously expected right after the runaway. For about 0.5 to 1 sec, the speed of the burning front will neither be determined by the laminar speed nor the Rayleigh-Taylor instabilities but by convective flows produced prior to the runaway. The consequences are discussed for our under- standing of the detailed physics of the flame propagation, the deflagration detonation transition, and the nucleosynthesis in the central layers. Our results strongly suggest the pre-conditioning of the progenitor as a key-factor for our understanding of the diversity in SNeIa.

P. Hoeflich; J. Stein

2001-12-07T23:59:59.000Z

377

Enhancement of Resonant Thermonuclear Reaction Rates in Extremely Dense Stellar Plasmas  

E-Print Network [OSTI]

The enhancement factor of the resonant thermonuclear reaction rates is calculated for the extremely dense stellar plasmas in the liquid phase. In order to calculate the enhancement factor we use the screening potential which is deduced from the numerical experiment of the classical one-component plasma. It is found that the enhancement is tremendous for white dwarf densities if the ^{12}C + ^{12}C fusion cross sections show resonant behavior in the astrophysical energy range. We summarize our numerical results by accurate analytic fitting formulae.

Naoki Itoh; Nami Tomizawa; Shinya Wanajo; Satoshi Nozawa

2002-12-06T23:59:59.000Z

378

Charged-Particle Thermonuclear Reaction Rates: IV. Comparison to Previous Work  

E-Print Network [OSTI]

We compare our Monte Carlo reaction rates (see Paper II of this series) to previous results that were obtained by using the classical method of computing thermonuclear reaction rates. For each reaction, the comparison is presented using two types of graphs: the first shows the change in reaction rate uncertainties, while the second displays our new results normalized to the previously recommended reaction rate. We find that the rates have changed significantly for almost all reactions considered here. The changes are caused by (i) our new Monte Carlo method of computing reaction rates (see Paper I of this series), and (ii) newly available nuclear physics information (see Paper III of this series).

Christian Iliadis; Richard Longland; Art Champagne; Alain Coc

2010-04-23T23:59:59.000Z

379

English home Forum Photo Gallery Features Newsletter Archive About US Help Site Map languages Culture/Life  

E-Print Network [OSTI]

and tomorrow's electricity-producing fusion power plants. The new Chinese investment into the thermonuclear invests more into thermonuclear reaction study China's announced Friday in to invest 50 million yuan (6 million US dollars) more to the country's ongoing research on thermonuclear experimental reactors

380

Russian scientists to join round-the-world computer network ring. 28.01.2004, 21.08  

E-Print Network [OSTI]

in order to exchange with their foreign colleagues information on thermonuclear fusion and the creation thermonuclear experimental reactor (ITER) project have an opportunity to offer technical solutions for building of ITER, Velikhov said the decision on the site for the world' s first international thermonuclear

Note: This page contains sample records for the topic "thermonuclear experimental 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

A revised thermonuclear rate of $^{7}$Be($n$,$?$)$^{4}$He relevant to Big-Bang nucleosynthesis  

E-Print Network [OSTI]

In the standard Big-Bang nucleosynthesis (BBN) model, the primordial $^7$Li abundance is overestimated by about a factor of 2--3 comparing to the astronomical observations, so called the pending cosmological lithium problem. The $^7$Be($n$,$\\alpha$)$^4$He reaction, which may affect the $^7$Li abundance, was regarded as the secondary important reaction in destructing the $^7$Be nucleus in BBN. However, the thermonuclear rate of $^7$Be($n$,$\\alpha$)$^4$He has not been well studied so far. This reaction rate was firstly estimated by Wagoner in 1969, which has been generally adopted in the current BBN simulations and the reaction rate library. This simple estimation involved only a direct-capture reaction mechanism, but the resonant contribution should be also considered according to the later experimental results. In this work, we have revised this rate based on the indirect cross-section data available for the $^4$He($\\alpha$,$n$)$^7$Be and $^4$He($\\alpha$,$p$)$^7$Li reactions, with the charge symmetry and detailed-balance principle. Our new result shows that the previous rate (acting as an upper limit) is overestimated by about a factor of ten. The BBN simulation shows that the present rate leads to a 1.2\\% increase in the final $^7$Li abundance compared to the result using the Wagoner rate, and hence the present rate even worsens the $^7$Li problem. By the present estimation, the role of $^7$Be($n$,$\\alpha$)$^4$He in destroying $^7$Be is weakened from the secondary importance to the third, and the $^7$Be($d$,$p$)2$^4$He reaction becomes of secondary importance in destructing $^7$Be.

S. Q. Hou; J. J. He; S. Kubono; Y. S. Chen

2015-02-13T23:59:59.000Z

382

Relativistic collapse and explosion of rotating supermassive stars with thermonuclear effects  

E-Print Network [OSTI]

We present results of general relativistic simulations of collapsing supermassive stars with and without rotation using the two-dimensional general relativistic numerical code Nada, which solves the Einstein equations written in the BSSN formalism and the general relativistic hydrodynamics equations with high resolution shock capturing schemes. These numerical simulations use an equation of state which includes effects of gas pressure, and in a tabulated form those associated with radiation and the electron-positron pairs. We also take into account the effect of thermonuclear energy released by hydrogen and helium burning. We find that objects with a mass of 5x10^{5} solar mass and an initial metallicity greater than Z_{CNO}~0.007 do explode if non-rotating, while the threshold metallicity for an explosion is reduced to Z_{CNO}~0.001 for objects uniformly rotating. The critical initial metallicity for a thermonuclear explosion increases for stars with mass ~10^{6} solar mass. For those stars that do not explode we follow the evolution beyond the phase of black hole formation. We compute the neutrino energy loss rates due to several processes that may be relevant during the gravitational collapse of these objects. The peak luminosities of neutrinos and antineutrinos of all flavors for models collapsing to a BH are ~10^{55} erg/s. The total radiated energy in neutrinos varies between ~10^{56} ergs for models collapsing to a BH, and ~10^{45}-10^{46} ergs for models exploding.

Pedro J. Montero; Hans-Thomas Janka; Ewald Mueller

2012-02-01T23:59:59.000Z

383

Relics of metal-free low mass stars exploding as thermonuclear supernovae  

E-Print Network [OSTI]

Renewed interest in the first stars that were formed in the universe has led to the discovery of extremely iron-poor stars. Since several competing scenarios exist, our understanding of the mass range that determines the observed elemental abundances remains unclear. In this study, we consider three well-studied metal-poor stars in terms of the theoretical supernovae (SNe) model. Our results suggest that the observed abundance patterns in the metal-poor star BD +80 245 and the pair of stars HD 134439/40 agree strongly with the theoretical possibility that these stars inherited their heavy element abundance patterns from SNe initiated by thermonuclear runaways in the degenerate carbon-oxygen cores of primordial asymptotic giant branch stars with \\~3.5-5 solar masses. Recent theoretical calculations have predicted that such SNe could be originated from metal-free stars in the intermediate mass range. On the other hand, intermediate mass stars containing some metals would end their lives as white dwarfs after expelling their envelopes in the wind due to intense momentum transport from outgoing photons to heavy elements. This new pathway for the formation of SNe requires that stars are formed from the primordial gas. Thus, we suggest that stars of a few solar masses were formed from the primordial gas and that some of them caused thermonuclear explosions when the mass of their degenerate carbon-oxygen cores increased to the Chandrasekhar limit without experiencing efficient mass loss.

Takuji Tsujimoto; Toshikazu Shigeyama

2006-01-16T23:59:59.000Z

384

Level set simulations of turbulent thermonuclear deflagration in degenerate carbon and oxygen  

E-Print Network [OSTI]

We study the dynamics of thermonuclear flames propagating in fuel stirred by stochastic forcing. The fuel consists of carbon and oxygen in a state which is encountered in white dwarfs close to the Chandrasekhar limit. The level set method is applied to represent the flame fronts numerically. The computational domain for the numerical simulations is cubic, and periodic boundary conditions are imposed. The goal is the development of a suitable flame speed model for the small-scale dynamics of turbulent deflagration in thermonuclear supernovae. Because the burning process in a supernova explosion is transient and spatially inhomogeneous, the localised determination of subgrid scale closure parameters is essential. We formulate a semi-localised model based on the dynamical equation for the subgrid scale turbulence energy $k_{\\mathrm{sgs}}$. The turbulent flame speed $s_{\\mathrm{t}}$ is of the order $\\sqrt{2k_{\\mathrm{sgs}}}$. In particular, the subgrid scale model features a dynamic procedure for the calculation of the turbulent energy transfer from resolved toward subgrid scales, which has been successfully applied to combustion problems in engineering. The options of either including or suppressing inverse energy transfer in the turbulence production term are compared. In combination with the piece-wise parabolic method for the hydrodynamics, our results favour the latter option. Moreover, different choices for the constant of proportionality in the asymptotic flame speed relation, $s_{\\mathrm{t}}\\propto\\sqrt{2k_{\\mathrm{sgs}}}$, are investigated.

W. Schmidt; W. Hillebrandt; J. C. Niemeyer

2005-08-02T23:59:59.000Z

385

Thermonuclear Burning on the Accreting X-Ray Pulsar GRO J1744-28  

E-Print Network [OSTI]

We investigate the thermal stability of nuclear burning on the accreting X-ray pulsar GRO J1744-28. The neutron star's dipolar magnetic field is thermonuclear instabilities are unlikely causes of the hourly bursts seen at very high accretion rates. We then discuss how the stability of the thermonuclear burning depends on both the global accretion rate and the neutron star's magnetic field strength. We emphasize that the appearance of the instability (i.e., whether it looks like a Type I X-ray burst or a flare lasting a few minutes) will yield crucial information on the neutron star's surface magnetic field and the role of magnetic fields in convection. We suggest that a thermal instability in the accretion disk is the origin of the long (~300 days) outburst and that the recurrence time of these outbursts is >50 years. We also discuss the nature of the binary and point out that a velocity measurement of the stellar companion (most likely a Roche-lobe filling giant with m_K>17) will constrain the neutron star mass.

Lars Bildsten; Edward F. Brown

1996-09-23T23:59:59.000Z

386

Magnetic burial and the harmonic content of millisecond oscillations in thermonuclear X-ray bursts  

E-Print Network [OSTI]

Matter accreting onto the magnetic poles of a neutron star spreads under gravity towards the magnetic equator, burying the polar magnetic field and compressing it into a narrow equatorial belt. Steady-state, Grad-Shafranov calculations with a self-consistent mass-flux distribution (and a semi-quantitative treatment of Ohmic diffusion) show that, for $\\Ma \\gtrsim 10^{-5}\\Msun$, the maximum field strength and latitudinal half-width of the equatorial magnetic belt are $B_{\\rm max} = 5.6\\times 10^{15} (\\Ma/10^{-4}\\Msun)^{0.32}$ G and $\\Delta\\theta = \\max[3^{\\circ} (\\Ma/10^{-4}\\Msun)^{-1.5},3^{\\circ} (\\Ma/10^{-4}\\Msun)^{0.5}(\\dot{M}_{\\rm a}/10^{-8}\\Msun {\\rm yr}^{-1})^{-0.5}]$ respectively, where $\\Ma$ is the total accreted mass and $\\dot{M}_{\\rm a}$ is the accretion rate. It is shown that the belt prevents north-south heat transport by conduction, convection, radiation, and ageostrophic shear. This may explain why millisecond oscillations observed in the tails of thermonuclear (type I) X-ray bursts in low-mass X-ray binaries are highly sinusoidal: the thermonuclear flame is sequestered in the magnetic hemisphere which ignites first. The model is also consistent with the occasional occurrence of closely spaced pairs of bursts. Time-dependent, ideal-magnetohydrodynamic simulations confirm that the equatorial belt is not disrupted by Parker and interchange instabilities.

D. J. B. Payne; A. Melatos

2006-07-11T23:59:59.000Z

387

Thermonuclear Flame Spreading on Rapidly Spinning Neutron Stars: Indications of the Coriolis Force?  

E-Print Network [OSTI]

Millisecond period brightness oscillations during the intensity rise of thermonuclear X-ray bursts are likely caused by an azimuthally asymmetric, expanding burning region on the stellar surface. The time evolution of the oscillation amplitude during the intensity rise encodes information on how the thermonuclear flames spread across the stellar surface. This process depends on properties of the accreted burning layer, surface fluid motions, and the surface magnetic field structure, and thus can provide insight into these stellar properties. We present two examples of bursts from different sources that show a decrease in oscillation amplitude during the intensity rise. Using theoretical modeling, we demonstrate that the observed amplitude evolution of these bursts is not well described by a uniformly expanding circular burning region. We further show that by including in our model the salient aspects of the Coriolis force (as described by Spitkovsky, Levin, and Ushomirsky) we can qualitatively reproduce the observed evolution curves. Our modeling shows that the evolutionary structure of burst oscillation amplitude is sensitive to the nature of flame spreading, while the actual amplitude values can be very useful to constrain some source parameters.

Sudip Bhattacharyya; Tod E. Strohmayer

2007-08-27T23:59:59.000Z

388

thermonuclear functions  

E-Print Network [OSTI]

Two representations of the extended gamma functions ? 2,0 0,2 [(b,x)] are proved. These representations are exploited to find a transformation relation between two Fox’s H-functions. These results are used to solve Fox’s H-function in terms of Meijer’s G-function for certain values of the parameters. A closed form representation of the kernel of the Bessel type integral transform is also proved. 1.

M. Aslam Chaudhry

1999-01-01T23:59:59.000Z

389

Pyroprocessing of Oxidized Sodium-Bonded Fast Reactor Fuel -- an Experimental Study of Treatment Options for Degraded EBR-II Fuel  

SciTech Connect (OSTI)

An experimental study was conducted to assess pyrochemical treatment options for degraded EBR-II fuel. As oxidized material, the degraded fuel would need to be converted back to metal to enable electrorefining within an existing electrometallurgical treatment process. A lithium-based electrolytic reduction process was studied to assess the efficacy of converting oxide materials to metal with a particular focus on the impact of zirconium oxide and sodium oxide on this process. Bench-scale electrolytic reduction experiments were performed in LiCl-Li2O at 650 °C with combinations of manganese oxide (used as a surrogate for uranium oxide), zirconium oxide, and sodium oxide. The experimental study illustrated how zirconium oxide and sodium oxide present different challenges to a lithium-based electrolytic reduction system for conversion of select metal oxides to metal.

S. D. Herrmann; L. A. Wurth; N. J. Gese

2013-09-01T23:59:59.000Z

390

Analysis and synthesis techniques of nonlinear dynamical systems with applications to diagnostic of controlled thermonuclear fusion reactors.  

E-Print Network [OSTI]

??Nonlinear dynamical systems are of wide interest to engineers, physicists and mathematicians, and this is due to the fact that most of physical systems in… (more)

Pisano, Fabio

2013-01-01T23:59:59.000Z

391

The Conception of Thermonuclear Reactor on the Principle of Gravitational Confinement of Dense High-temperature Plasma  

E-Print Network [OSTI]

The work of Fisenko S. I., & Fisenko I. S. (2009). The old and new concepts of physics, 6 (4), 495, shows the key fact of the existence of gravitational radiation as a radiation of the same level as electromagnetic. The obtained results strictly correspond to the framework of relativistic theory of gravitation and quantum mechanics. The given work contributes into further elaboration of the findings considering their application to dense high-temperature plasma of multiple-charge ions. This is due to quantitative character of electron gravitational emission spectrum such that amplification of gravitational emission may take place only in multiple-charge ion high-temperature plasma.

Stanislav Fisenko; Igor Fisenko

2010-06-27T23:59:59.000Z

392

Model based multivariable controller for large scale compression stations. Design and experimental validation on the LHC 18KW cryorefrigerator  

SciTech Connect (OSTI)

In this paper, a multivariable model-based non-linear controller for Warm Compression Stations (WCS) is proposed. The strategy is to replace all the PID loops controlling the WCS with an optimally designed model-based multivariable loop. This new strategy leads to high stability and fast disturbance rejection such as those induced by a turbine or a compressor stop, a key-aspect in the case of large scale cryogenic refrigeration. The proposed control scheme can be used to have precise control of every pressure in normal operation or to stabilize and control the cryoplant under high variation of thermal loads (such as a pulsed heat load expected to take place in future fusion reactors such as those expected in the cryogenic cooling systems of the International Thermonuclear Experimental Reactor ITER or the Japan Torus-60 Super Advanced fusion experiment JT-60SA). The paper details how to set the WCS model up to synthesize the Linear Quadratic Optimal feedback gain and how to use it. After preliminary tuning at CEA-Grenoble on the 400W@1.8K helium test facility, the controller has been implemented on a Schneider PLC and fully tested first on the CERN's real-time simulator. Then, it was experimentally validated on a real CERN cryoplant. The efficiency of the solution is experimentally assessed using a reasonable operating scenario of start and stop of compressors and cryogenic turbines. This work is partially supported through the European Fusion Development Agreement (EFDA) Goal Oriented Training Program, task agreement WP10-GOT-GIRO.

Bonne, François; Bonnay, Patrick [INAC, SBT, UMR-E 9004 CEA/UJF-Grenoble, 17 rue des Martyrs, 38054 Grenoble (France); Alamir, Mazen [Gipsa-Lab, Control Systems Department, CNRS-University of Grenoble, 11, rue des Mathématiques, BP 46, 38402 Saint Martin d'Hères (France); Bradu, Benjamin [CERN, CH-1211 Genève 23 (Switzerland)

2014-01-29T23:59:59.000Z

393

U.S. to join research effort for fusion power Friday, January 31, 2003 file:///Macintosh%20HD/Desktop%20Folder/ITER%20Negotiations/MSNBC/  

E-Print Network [OSTI]

, the International Thermonuclear Experimental Reactor, is a fusion research project that is already a joint operationU.S. to join research effort for fusion power Friday, January 31, 2003 file:///Macintosh%20HD view of the proposed International Thermonuclear Experimental Reactor, with a central containment

394

PPPL3171 Preprint Date: May 1996, UC421, 423, 427 Simulations of alpha particle ripple loss from the  

E-Print Network [OSTI]

International Thermonuclear Experimental Reactor (ITER) [Plasma Physics and Controlled Nuclear Fusion Research from the International Thermonuclear Experimental Reactor M. H. Redi, R. V. Budny, D. C. McCune, C. O of the ripple minimum for D shaped ripple contours. In contrast to alpha loss simulations for the Tokamak Fusion

395

TB, AP, UK, JPhysB/330302, 29/12/2009 IOP PUBLISHING JOURNAL OF PHYSICS B: ATOMIC, MOLECULAR AND OPTICAL PHYSICS  

E-Print Network [OSTI]

Thermonuclear Experimental Reactor. (Some figures in this article are in colour only in the electronic version for future experiments at the International Thermonuclear Experimental Reactor (ITER). The effect, spectroscopy of highly charged tungsten ions relevant to fusion plasmas was recently discussed by Biedermann et

Johnson, Walter R.

396

Plasma Barodiffusion in Inertial-Confinement-Fusion Implosions: Application to Observed Yield Anomalies in Thermonuclear Fuel Mixtures  

E-Print Network [OSTI]

Anomalies in Thermonuclear Fuel Mixtures Peter Amendt, O. L. Landen, and H. F. Robey Lawrence Livermore National Laboratory, Livermore, California 94551, USA C. K. Li and R. D. Petrasso Plasma Science and Fusion performance in general, and upcoming igni- tion tuning campaigns on the National Ignition Facility (NIF) [4

397

Spreading of thermonuclear flames on the neutron star in SAX J1808.4-3658: an observational tool  

E-Print Network [OSTI]

We analyse archival Rossi X-Ray Timing Explorer (RXTE) proportional counter array (PCA) data of thermonuclear X-ray bursts from the 2002 outburst of the accreting millisecond pulsar SAX J1808.4-3658. We present evidence of nonmonotonic variations of oscillation frequency during burst rise, and correlations among the time evolution of the oscillation frequency, amplitude, and the inferred burning region area. We also discuss that the amplitude and burning region area evolutions are consistent with thermonuclear flame spreading on the neutron star surface. Based on this discussion, we infer that for the 2002 Oct. 15 thermonuclear burst, the ignition likely occured in the mid-latitudes, the burning region took ~ 0.2 s to nearly encircle the equatorial region of the neutron star, and after that the lower amplitude oscillation originated from the remaining asymmetry of the burning front in the same hemisphere where the burst ignited. Our observational findings and theoretical discussion indicate that studies of the evolution of burst oscillation properties during burst rise can provide a powerful tool to understand thermonuclear flame spreading on neutron star surfaces under extreme physical conditions.

Sudip Bhattacharyya; Tod E. Strohmayer

2006-04-03T23:59:59.000Z

398

Thermonuclear yield of targets under the action of high-power short-wavelength (lambda< or =1. mu. ) lasers  

SciTech Connect (OSTI)

A unified optimization scheme is used in a numerical calculation of the dependences of the thermonuclear yield of two-layer shell targets on the absorbed laser energy in the range 0.3--10 mJ for lasers emitting radiation of wavelengths shorter than 1 ..mu...

Basov, N.G.; Gus'kov, S.Y.; Danilova, G.V.; Demchenko, N.N.; Zmitrenko, N.V.; Karpov, V.Y.; Mishchenko, T.V.; Rozanov, V.B.; Samarskii, A.A.

1985-06-01T23:59:59.000Z

399

University Reactor Matching Grants Program  

SciTech Connect (OSTI)

During the 2002 Fiscal year, funds from the DOE matching grant program, along with matching funds from the industrial sponsors, have been used to support research in the area of thermal-hydraulics. Both experimental and numerical research projects have been performed. Experimental research focused on two areas: (1) Identification of the root cause mechanism for axial offset anomaly in pressurized water reactors under prototypical reactor conditions, and (2) Fluid dynamic aspects of thin liquid film protection schemes for inertial fusion reactor chambers. Numerical research focused on two areas: (1) Multi-fluid modeling of both two-phase and two-component flows for steam conditioning and mist cooling applications, and (2) Modeling of bounded Rayleigh-Taylor instability with interfacial mass transfer and fluid injection through a porous wall simulating the ''wetted wall'' protection scheme in inertial fusion reactor chambers. Details of activities in these areas are given.

John Valentine; Farzad Rahnema; Said Abdel-Khalik

2003-02-14T23:59:59.000Z

400

Photo of the Week: The Sixth Zero Power Reactor | Department...  

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

to the construction of the Experimental Breeder Reactor-II, a sodium-cooled fast reactor power plant. In this 1970 photo, an Argonne scientist is loading the matrices of the...

Note: This page contains sample records for the topic "thermonuclear experimental 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

The fastest unbound star in our Galaxy ejected by a thermonuclear supernova  

E-Print Network [OSTI]

Hypervelocity stars (HVS) travel with velocities so high, that they exceed the escape velocity of the Galaxy. Several acceleration mechanisms have been discussed. Only one HVS (US 708, HVS 2) is a compact helium star. Here we present a spectroscopic and kinematic analysis of US\\,708. Travelling with a velocity of $\\sim1200\\,{\\rm km\\,s^{-1}}$, it is the fastest unbound star in our Galaxy. In reconstructing its trajectory, the Galactic center becomes very unlikely as an origin, which is hardly consistent with the most favored ejection mechanism for the other HVS. Furthermore, we discovered US\\,708 to be a fast rotator. According to our binary evolution model it was spun-up by tidal interaction in a close binary and is likely to be the ejected donor remnant of a thermonuclear supernova.

Geier, S; Ziegerer, E; Kupfer, T; Heber, U; Irrgang, A; Wang, B; Liu, Z; Han, Z; Sesar, B; Levitan, D; Kotak, R; Magnier, E; Smith, K; Burgett, W S; Chambers, K; Flewelling, H; Kaiser, N; Wainscoat, R; Waters, C

2015-01-01T23:59:59.000Z

402

Thermonuclear Processes for Three Body System in the Potential Cluster Model  

E-Print Network [OSTI]

The manuscript is devoted to the description of the results obtained in the frame of the modified potential cluster model with the classification of states according to Young tableaux for neutron and proton radiative capture processes on 2H at thermal and astrophysical energies. It demonstrates methods of application that were obtained on the basis of phase shift analysis and characteristics of the bound states of 2H potentials for consideration of the radiative capture processes. First reaction of the proton capture directly takes part in the pp solar cycle, where it is the second reaction. The neutron capture is not a part of usual thermonuclear cycles in the Sun and stars, but can take part in the processes of primordial nucleosynthesis, following at formation and evolution of our entire Universe.

S. B. Dubovichenko; A. V. Dzhazairov-Kakhramanov

2015-04-19T23:59:59.000Z

403

Thermonuclear Processes for Three Body System in the Potential Cluster Model  

E-Print Network [OSTI]

The manuscript is devoted to the description of the results obtained in the frame of the modified potential cluster model with the classification of states according to Young tableaux for neutron and proton radiative capture processes on 2H at thermal and astrophysical energies. It demonstrates methods of application that were obtained on the basis of phase shift analysis and characteristics of the bound states of 2H potentials for consideration of the radiative capture processes. First reaction of the proton capture directly takes part in the pp solar cycle, where it is the second reaction. The neutron capture is not a part of usual thermonuclear cycles in the Sun and stars, but can take part in the processes of primordial nucleosynthesis, following at formation and evolution of our entire Universe.

Dubovichenko, S B

2015-01-01T23:59:59.000Z

404

On the small-scale stability of thermonuclear flames in Type Ia supernovae  

E-Print Network [OSTI]

We present a numerical model which allows us to investigate thermonuclear flames in Type Ia supernova explosions. The model is based on a finite-volume explicit hydrodynamics solver employing PPM. Using the level-set technique combined with in-cell reconstruction and flux-splitting schemes we are able to describe the flame in the discontinuity approximation. We apply our implementation to flame propagation in Chandrasekhar-mass Type Ia supernova models. In particular we concentrate on intermediate scales between the flame width and the Gibson-scale, where the burning front is subject to the Landau-Darrieus instability. We are able to reproduce the theoretical prediction on the growth rates of perturbations in the linear regime and observe the stabilization of the flame in a cellular shape. The increase of the mean burning velocity due to the enlarged flame surface is measured. Results of our simulation are in agreement with semianalytical studies.

F. K. Roepke; J. C. Niemeyer; W. Hillebrandt

2003-05-02T23:59:59.000Z

405

Analysis of the Thermonuclear Instability including Low-Power ICRH Minority Heating in IGNITOR  

E-Print Network [OSTI]

The nonlinear thermal balance equation for classical plasma in a toroidal geometry is analytically and numerically investigated including ICRH power. The determination of the equilibrium temperature and the analysis of the stability of the solution are performed by solving the energy balance equation that includes the transport relations obtained by the kinetic theory. An estimation of the confinement time is also provided. We show that the ICRH heating in the IGNITOR experiment, among other applications, is expected to stabilize the power of the thermonuclear burning by automatic regulation of the RF coupled power. Here a scenario is considered where IGNITOR is led to operate in a slightly sub-critical regime by adding a small fraction of ${}^3He$ to the nominal 50-50 Deuterium-Tritium mixture. The difference between power lost and alpha heating is compensated by additional ICRH heating, which should be able to increase the global plasma temperature via collisions between ${}^3He$ minority and the background...

Cardinali, Alessandro

2014-01-01T23:59:59.000Z

406

Spiral Disk Instability Can Drive Thermonuclear Explosions in Binary White Dwarf Mergers  

E-Print Network [OSTI]

Thermonuclear, or Type Ia supernovae (SNe Ia), originate from the explosion of carbon-oxygen white dwarfs, and serve as standardizable cosmological candles. However, despite their importance, the nature of the progenitor systems which give rise to SNe Ia has not been hitherto elucidated. Observational evidence favors the double-degenerate channel, in which merging white dwarf binaries lead to SNe Ia. Furthermore, significant discrepancies exist between observations and theory, and to date, there has been no self-consistent merger model which yields a SNe Ia. Here we show that a spiral mode instability in the accretion disk formed during a binary white dwarf merger leads to a detonation on a dynamical timescale. This mechanism sheds light on how white dwarf mergers may frequently yield SNe Ia.

Kashyap, Rahul; García-Berro, Enrique; Aznar-Siguán, Gabriela; Ji, Suoqing; Lorén-Aguilar, Pablo

2015-01-01T23:59:59.000Z

407

Astrophysics Simulations from the ASC/Alliances Center for Astrophysical Thermonuclear Flashes  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

The "Flash Center" works to solve the long-standing problem of thermonuclear flashes on the surfaces of compact stars such as neutron stars and white dwarfs, and in the interior of white dwarfs (i.e., Type I supernovae). The physical conditions, and many of the physical phenomena, are similar to those confronted by the Department of Energy Stockpile Stewardship program. The (fully ionized) plasmas are at very high temperatures and densities; and the physical problems of nuclear ignition, deflagration or detonation, turbulent mixing, and interface dynamics for complex multicomponent fluids are common to the weapons program. Because virtually every aspect of this problem represents a computational Grand Challenge, large-scale numerical simulations are at the heart of its resolution (Taken from Executive Summary page). More than 35 simulations and computer animations developed through research at the "Flash Center" are available here. Each .avi or .mov file also references the related research paper or presentation and provides a link.

408

Thermonuclear Burning Regimes and the Use of SNe Ia in Cosmology  

E-Print Network [OSTI]

The calculations of the light curves of thermonuclear supernovae are carried out by a method of multi-group radiation hydrodynamics. The effects of spectral lines and expansion opacity are taken into account. The predictions for UBVI fluxes are given. The values of rise time for B and V bands found in our calculations are in good agreement with the observed values. We explain why our results for the rise time have more solid physical justification than those obtained by other authors. It is shown that small variations in the chemical composition of the ejecta, produced in the explosions with different regimes of nuclear burning, can influence drastically the light curve decline in the B band and, to a lesser extent, in the V band. We argue that recent results on positive cosmological constant Lambda, found from the high redshift supernova observations, could be wrong in the case of possible variations of the preferred mode of nuclear burning in the earlier Universe.

E. I. Sorokina; S. I. Blinnikov; O. S. Bartunov

1999-10-02T23:59:59.000Z

409

Oxygen emission in remnants of thermonuclear supernovae as a probe for their progenitor system  

E-Print Network [OSTI]

Recent progress in numerical simulations of thermonuclear supernova explosions brings up a unique opportunity in studying the progenitors of Type Ia supernovae. Coupling state-of-the-art explosion models with detailed hydrodynamical simulations of the supernova remnant evolution and the most up-to-date atomic data for X-ray emission calculations makes it possible to create realistic synthetic X-ray spectra for the supernova remnant phase. Comparing such spectra with high quality observations of supernova remnants could allow to constrain the explosion mechanism and the progenitor of the supernova. The present study focuses in particular on the oxygen emission line properties in young supernova remnants, since different explosion scenarios predict a different amount and distribution of this element. Analysis of the soft X-ray spectra from supernova remnants in the Large Magellanic Cloud and confrontation with remnant models for different explosion scenarios suggests that SNR 0509-67.5 could originate from a de...

Kosenko, D; Kromer, M; Blinnikov, S I; Pakmor, R; Kaastra, J S

2014-01-01T23:59:59.000Z

410

Registration of the First Thermonuclear X-ray Burst from AX J1754.2-2754  

E-Print Network [OSTI]

During the analysis of the INTEGRAL observatory archival data we found a powerful X-ray burst, registered by JEM-X and IBIS/ISGRI telescopes on April 16, 2005 from a weak and poorly known source AX J1754.2-2754. Analysis of the burst profiles and spectrum shows, that it was a type I burst, which result from thermonuclear explosion on the surface of nutron star. It means that we can consider AX J1754.2-2754 as an X-ray burster. Certain features of burst profile at its initial stage witness of a radiation presure driven strong expansion and a corresponding cooling of the nutron star photosphere. Assuming, that the luminosity of the source at this phase was close to the Eddington limit, we estimated the distance to the burst source d=6.6+/-0.3 kpc (for hidrogen atmosphere of the neutron star) and d=9.2+/-0.4 kpc (for helium atmosphere).

I. V. Chelovekov; S. A. Grebenev

2007-10-30T23:59:59.000Z

411

Small-scale Interaction of Turbulence with Thermonuclear Flames in Type Ia Supernovae  

E-Print Network [OSTI]

Microscopic turbulence-flame interactions of thermonuclear fusion flames occuring in Type Ia Supernovae were studied by means of incompressible direct numerical simulations with a highly simplified flame description. The flame is treated as a single diffusive scalar field with a nonlinear source term. It is characterized by its Prandtl number, Pr << 1, and laminar flame speed, S_L. We find that if S_L ~ u', where u' is the rms amplitude of turbulent velocity fluctuations, the local flame propagation speed does not significantly deviate from S_L even in the presence of velocity fluctuations on scales below the laminar flame thickness. This result is interpreted in the context of subgrid-scale modeling of supernova explosions and the mechanism for deflagration-detonation-transitions.

J. C. Niemeyer; W. K. Bushe; G. R. Ruetsch

1999-05-07T23:59:59.000Z

412

Nuclear reactor engineering  

SciTech Connect (OSTI)

Chapters are presented concerning energy from nuclear fission; nuclear reactions and radiations; diffusion and slowing-down of neutrons; principles of reactor analysis; nuclear reactor kinetics and control; energy removal; non-fuel reactor materials; the reactor fuel system; radiation protection and environmental effects; nuclear reactor shielding; nuclear reactor safety; and power reactor systems.

Glasstone, S.; Sesonske, A.

1981-01-01T23:59:59.000Z

413

Research reactors - an overview  

SciTech Connect (OSTI)

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

414

Light Water Reactor Sustainability  

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

3 Light Water Reactor Sustainability Program ACCOMPLISHMENTS REPORT 2013 Accomplishments Report | Light Water Reactor Sustainability 2 T he mission of the Light Water Reactor...

415

Light Water Reactor Sustainability  

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

416

Pyroprocessing of oxidized sodium-bonded fast reactor fuel - An experimental study of treatment options for degraded EBR-II fuel  

SciTech Connect (OSTI)

An experimental study was conducted to assess pyrochemical treatment options for degraded EBR-II fuel. As oxidized material, the degraded fuel would need to be converted back to metal to enable electrorefining within an existing electro-metallurgical treatment process. A lithium-based electrolytic reduction process was studied to assess the efficacy of converting oxide materials to metal with a particular focus on the impact of zirconium oxide and sodium oxide on this process. Bench-scale electrolytic reduction experiments were performed in LiCl-Li{sub 2}O at 650 C. degrees with combinations of manganese oxide (used as a surrogate for uranium oxide), zirconium oxide, and sodium oxide. In the absence of zirconium or sodium oxide, the electrolytic reduction of MnO showed nearly complete conversion to metal. The electrolytic reduction of a blend of MnO-ZrO{sub 2} in LiCl - 1 wt% Li{sub 2}O showed substantial reduction of manganese, but only 8.5% of the zirconium was found in the metal phase. The electrolytic reduction of the same blend of MnO-ZrO{sub 2} in LiCl - 1 wt% Li{sub 2}O - 6.2 wt% Na{sub 2}O showed substantial reduction of manganese, but zirconium reduction was even less at 2.4%. This study concluded that ZrO{sub 2} cannot be substantially reduced to metal in an electrolytic reduction system with LiCl - 1 wt% Li{sub 2}O at 650 C. degrees due to the perceived preferential formation of lithium zirconate. This study also identified a possible interference that sodium oxide may have on the same system by introducing a parasitic and cyclic reaction of dissolved sodium metal between oxidation at the anode and reduction at the cathode. When applied to oxidized sodium-bonded EBR-II fuel (e.g., U-10Zr), the prescribed electrolytic reduction system would not be expected to substantially reduce zirconium oxide, and the accumulation of sodium in the electrolyte could interfere with the reduction of uranium oxide, or at least render it less efficient.

Hermann, S.D.; Gese, N.J. [Separations Department, Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415 (United States); Wurth, L.A. [Zinc Air Inc., 5314-A US Hwy 2 West, Columbia Falls, MT 59912 (United States)

2013-07-01T23:59:59.000Z

417

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

418

Bioconversion reactor  

DOE Patents [OSTI]

A bioconversion reactor for the anaerobic fermentation of organic material. The bioconversion reactor comprises a shell enclosing a predetermined volume, an inlet port through which a liquid stream containing organic materials enters the shell, and an outlet port through which the stream exits the shell. A series of vertical and spaced-apart baffles are positioned within the shell to force the stream to flow under and over them as it passes from the inlet to the outlet port. The baffles present a barrier to the microorganisms within the shell causing them to rise and fall within the reactor but to move horizontally at a very slow rate. Treatment detention times of one day or less are possible.

McCarty, Perry L. (Stanford, CA); Bachmann, Andre (Palo Alto, CA)

1992-01-01T23:59:59.000Z

419

Research project -Master Thesis Investigation of mixed rare earth  

E-Print Network [OSTI]

's) to fusion devices such as the International Thermonuclear Experimental Reactor (ITER) to superconducting emission-free energy by means of supercon- ducting generators for windmills, fusion reactors etc

420

REACTOR ENGINEERING DIVISION QUARTERLY REPORT FOR DECEMBER 1...  

Office of Scientific and Technical Information (OSTI)

reactor (physics, thermal analysis, and experimental and development program); corrosion of Al coating: irradiation of wax and lubricants; effect of long-term irradiation on...

Note: This page contains sample records for the topic "thermonuclear experimental 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

Advanced Safeguards Approaches for New Fast Reactors  

SciTech Connect (OSTI)

This third report in the series reviews possible safeguards approaches for new fast reactors in general, and the ABR in particular. Fast-neutron spectrum reactors have been used since the early 1960s on an experimental and developmental level, generally with fertile blanket fuels to “breed” nuclear fuel such as plutonium. Whether the reactor is designed to breed plutonium, or transmute and “burn” actinides depends mainly on the design of the reactor neutron reflector and the whether the blanket fuel is “fertile” or suitable for transmutation. However, the safeguards issues are very similar, since they pertain mainly to the receipt, shipment and storage of fresh and spent plutonium and actinide-bearing “TRU”-fuel. For these reasons, the design of existing fast reactors and details concerning how they have been safeguarded were studied in developing advanced safeguards approaches for the new fast reactors. In this regard, the design of the Experimental Breeder Reactor-II “EBR-II” at the Idaho National Laboratory (INL) was of interest, because it was designed as a collocated fast reactor with a pyrometallurgical reprocessing and fuel fabrication line – a design option being considered for the ABR. Similarly, the design of the Fast Flux Facility (FFTF) on the Hanford Site was studied, because it was a successful prototype fast reactor that ran for two decades to evaluate fuels and the design for commercial-scale fast reactors.

Durst, Philip C.; Therios, Ike; Bean, Robert; Dougan, A.; Boyer, Brian; Wallace, Rick L.; Ehinger, Michael H.; Kovacic, Don N.; Tolk, K.

2007-12-15T23:59:59.000Z

422

78 PHYSICAL SCHEMES OF EXPERIMENTAL DEVICES WITH DISK EMG FOR FEASIBILITY STUDY OF THERMONUCLEAR IGNITION IN MAGO SYSTEM  

E-Print Network [OSTI]

The use of magnetic hydrodynamic compression system (MAGO/MTF) (1,2) is one of the approaches in handling the ignition problem. MAGO system consists of two main parts – the preheating system for magnetized D-T plasma and a plasma compression system. To obtain heated magnetized plasma we use a special MAGO chamber (1) , which consists of two toroidal cells conjoined with a narrow annular nozzle. Magnetized plasma is accelerated in the nozzle to ~ 1000 km/s velocities and heated in generated collisionless shock waves. A further compression of plasma in the second cell is required to com up to ignition parameters. Scheme of quasi-spherical target connected to the multi-module DEMG with the radial-coaxial transmission line (TL) 1. Detonators 2. DEMG HE disk charges 3. Metal DEMG magnetic flux compression cavities 4. Explosive unit of DEMG disconnection from helical EMG (HEMG). The paper justifies principal parameters for some physical schemes of devices with

V. B. Yakubov

423

Failure of a neutrino-driven explosion after core-collapse may lead to a thermonuclear supernova  

E-Print Network [OSTI]

We demonstrate that $\\sim10$ seconds after core-collapse of a massive star, a thermonuclear explosion of the outer shells is possible for some (tuned) initial density and composition profiles, assuming the neutrinos failed to explode the star. The explosion may lead to a successful supernova, as first suggested by Burbidge, Burbidge, Fowler and Hoyle (1957). We perform a series of one-dimensional (1D) calculations of collapsing massive stars with simplified initial density profiles (similar to the results of stellar evolution calculations) and various compositions (not similar to 1D stellar evolution calculations). We assume that the neutrinos escaped with negligible effect on the outer layers, which inevitably collapse. As the shells collapse, they compress and heat up adiabatically, enhancing the rate of thermonuclear burning. In some cases, where significant shells of mixed helium and oxygen are present with pre-collapsed burning times of $\\lesssim100\\,\\textrm{s}$ ($\\approx10$ times the free-fall time), a ...

Kushnir, Doron

2014-01-01T23:59:59.000Z

424

Igniting the Light Elements: The Los Alamos Thermonuclear Weapon Project, 1942-1952  

SciTech Connect (OSTI)

The American system of nuclear weapons research and development was conceived and developed not as a result of technological determinism, but by a number of individual architects who promoted the growth of this large technologically-based complex. While some of the technological artifacts of this system, such as the fission weapons used in World War II, have been the subject of many historical studies, their technical successors--fusion (or hydrogen) devices--are representative of the largely unstudied highly secret realms of nuclear weapons science and engineering. In the postwar period a small number of Los Alamos Scientific Laboratory's staff and affiliates were responsible for theoretical work on fusion weapons, yet the program was subject to both the provisions and constraints of the US Atomic Energy Commission, of which Los Alamos was a part. The Commission leadership's struggle to establish a mission for its network of laboratories, least of all to keep them operating, affected Los Alamos's leaders' decisions as to the course of weapons design and development projects. Adapting Thomas P. Hughes's ''large technological systems'' thesis, I focus on the technical, social, political, and human problems that nuclear weapons scientists faced while pursuing the thermonuclear project, demonstrating why the early American thermonuclear bomb project was an immensely complicated scientific and technological undertaking. I concentrate mainly on Los Alamos Scientific Laboratory's Theoretical, or T, Division, and its members' attempts to complete an accurate mathematical treatment of the ''Super''--the most difficult problem in physics in the postwar period--and other fusion weapon theories. Although tackling a theoretical problem, theoreticians had to address technical and engineering issues as well. I demonstrate the relative value and importance of H-bomb research over time in the postwar era to scientific, politician, and military participants in this project. I analyze how and when participants in the H-bomb project recognized both blatant and subtle problems facing the project, how scientists solved them, and the relationship this process had to official nuclear weapons policies. Consequently, I show how the practice of nuclear weapons science in the postwar period became an extremely complex, technologically-based endeavor.

Anne C. Fitzpatrick

1999-07-01T23:59:59.000Z

425

Neutronic reactor  

DOE Patents [OSTI]

A nuclear reactor includes an active portion with fissionable fuel and neutron moderating material surrounded by neutron reflecting material. A control element in the active portion includes a group of movable rods constructed of neutron-absorbing material. Each rod is movable with respect to the other rods to vary the absorption of neutrons and effect control over neutron flux.

Wende, Charles W. J. (Augusta, GA); Babcock, Dale F. (Wilmington, DE); Menegus, Robert L. (Wilmington, DE)

1983-01-01T23:59:59.000Z

426

NACRE II: an update of the NACRE compilation of charged-particle-induced thermonuclear reaction rates for nuclei with mass number $A < 16$  

E-Print Network [OSTI]

An update of the NACRE compilation [Angulo et al., Nucl. Phys. A 656 (1999) 3] is presented. This new compilation, referred to as NACRE II, reports thermonuclear reaction rates for 34 charged-particle induced, two-body exoergic reactions on nuclides with mass number $A<16$, of which fifteen are particle-transfer reactions and the rest radiative capture reactions. When compared with NACRE, NACRE II features in particular (1) the addition to the experimental data collected in NACRE of those reported later, preferentially in the major journals of the field by early 2013, and (2) the adoption of potential models as the primary tool for extrapolation to very low energies of astrophysical $S$-factors, with a systematic evaluation of uncertainties. As in NACRE, the rates are presented in tabular form for temperatures in the $10^{6}$ $\\simeq\\leq$ T $\\leq$ $10^{10}$ K range. Along with the 'adopted' rates, their low and high limits are provided. The new rates are available in electronic form as part of the Brussels Library (BRUSLIB) of nuclear data. The NACRE II rates also supersede the previous NACRE rates in the Nuclear Network Generator (NETGEN) for astrophysics. [http://www.astro.ulb.ac.be/databases.html.

Yi Xu; Kohji Takahashi; Stephane Goriely; Marcel Arnould; Masahisa Ohta; Hiroaki Utsunomiya

2013-10-26T23:59:59.000Z

427

NACRE II: an update of the NACRE compilation of charged-particle-induced thermonuclear reaction rates for nuclei with mass number $A < 16$  

E-Print Network [OSTI]

An update of the NACRE compilation [Angulo et al., Nucl. Phys. A 656 (1999) 3] is presented. This new compilation, referred to as NACRE II, reports thermonuclear reaction rates for 34 charged-particle induced, two-body exoergic reactions on nuclides with mass number $A<16$, of which fifteen are particle-transfer reactions and the rest radiative capture reactions. When compared with NACRE, NACRE II features in particular (1) the addition to the experimental data collected in NACRE of those reported later, preferentially in the major journals of the field by early 2013, and (2) the adoption of potential models as the primary tool for extrapolation to very low energies of astrophysical $S$-factors, with a systematic evaluation of uncertainties. As in NACRE, the rates are presented in tabular form for temperatures in the $10^{6}$ $\\simeq\\leq$ T $\\leq$ $10^{10}$ K range. Along with the 'adopted' rates, their low and high limits are provided. The new rates are available in electronic form as part of the Brussels...

Xu, Yi; Goriely, Stephane; Arnould, Marcel; Ohta, Masahisa; Utsunomiya, Hiroaki

2013-01-01T23:59:59.000Z

428

Reactor physics project progress report no. 2  

E-Print Network [OSTI]

This is the second annual report in an experimental and theoretical program to develop and apply single and few element heterogeneous methods for the determination of reactor lattice parameters. During the period covered ...

Driscoll, Michael J.

1969-01-01T23:59:59.000Z

429

Seminar 1b-1.letnik, II.stopnja Deuterium depth profiling with  

E-Print Network [OSTI]

of most critical issues in the construction of thermonuclear reactor based on magnetic confiment of the deuterium-tritium operation of International Thermonuclear Experimental Reactor (ITER). ITER walls-facing materials in nuclear fusion research resulted in an increasing interest in quantitative profiling

Â?umer, Slobodan

430

Doubts Rise Over the Great Nuclear Promise Julio Godoy  

E-Print Network [OSTI]

that a thermonuclear reactor poses three technical problems: production of the elements to undergo fusion (deuterium over a decision to base the International Thermonuclear Experimental Reactor (ITER) in France seems to introduce new nuclear technology. It will seek a nuclear fusion of two hydrogen isotopes (deuterium which

431

Evidence for enhanced persistent emission during sub-Eddington thermonuclear bursts  

E-Print Network [OSTI]

The standard approach for time-resolved X-ray spectral analysis of thermonuclear bursts involves subtraction of the pre-burst emission as background. This approach implicitly assumes that the persistent flux remains constant throughout the burst. We reanalyzed 332 photospheric radius expansion bursts observed from 40 sources by the Rossi X-ray Timing Explorer, introducing a multiplicative factor $f_a$ to the persistent emission contribution in our spectral fits. We found that for the majority of spectra the best-fit value of $f_a$ is significantly greater than 1, suggesting that the persistent emission typically increases during a burst. Elevated $f_a$ values were not found solely during the radius expansion interval of the burst, but were also measured in the cooling tail. The modified model results in a lower average value of the $\\chi^2$ fit statistic, indicating superior spectral fits, but not yet to the level of formal statistical consistency for all the spectra. We interpret the elevated $f_a$ values as...

Worpel, Hauke; Price, Daniel J

2015-01-01T23:59:59.000Z

432

Thermonuclear reaction rate of 18O(p,gamma)19F  

E-Print Network [OSTI]

For stars between 0.8-8.0 solar masses, nucleosynthesis enters its final phase during the asymptotic giant branch (AGB) stage. During this evolutionary period, grain condensation occurs in the stellar atmosphere, and the star experiences significant mass loss. The production of presolar grains can often be attributed to this unique stellar environment. A subset of presolar oxide grains features dramatic 18O depletion that cannot be explained by the standard AGB star burning stages and dredge-up models. An extra mixing process, referred to as "cool bottom processing" (CBP), was proposed for low-mass AGB stars. The 18O depletion observed within certain stellar environments and within presolar grain samples may result from the 18O+p processes during CBP. We report here on a study of the 18O(p,gamma)19F reaction at low energies. Based on our new results, we found that the resonance at Er = 95 keV (lab) has a negligible affect on the reaction rate at the temperatures associated with CBP. We also determined that the direct capture S-factor is almost a factor of 2 lower than the previously recommended value at low energies. An improved thermonuclear reaction rate for 18O(p,gamma)19F is presented.

M. Q. Buckner; C. Iliadis; J. M. Cesaratto; C. Howard; T. B. Clegg; A. E. Champagne; S. Daigle

2012-12-05T23:59:59.000Z

433

Screened thermonuclear reactions and predictive stellar evolution of detached double-lined eclipsing binaries  

E-Print Network [OSTI]

The low energy fusion cross sections of charged-particle nuclear reactions (and the respective reaction rates) in stellar plasmas are enhanced due to plasma screening effects. We study the impact of those effects on predictive stellar evolution simulations for detached double-lined eclipsing binaries. We follow the evolution of binary systems (pre-main sequence or main sequence stars) with precisely determined radii and masses from 1.1Mo to 23Mo (from their birth until their present state). The results indicate that all the discrepancies between the screened and unscreened models (in terms of luminosity, stellar radius, and effective temperature) are within the observational uncertainties. Moreover, no nucleosynthetic or compositional variation was found due to screening corrections. Therefore all thermonuclear screening effects on the charged-particle nuclear reactions that occur in the binary stars considered in this work (from their birth until their present state) can be totally disregarded. In other words, all relevant charged-particle nuclear reactions can be safely assumed to take place in a vacuum, thus simplifying and accelerating the simulation processes.

Theodore Liolios; Theocharis Kosmas

2005-07-06T23:59:59.000Z

434

Evidence of thermonuclear flame spreading on neutron stars from burst rise oscillations  

E-Print Network [OSTI]

Burst oscillations during the rising phases of thermonuclear X-ray bursts are usually believed to originate from flame spreading on the neutron star surface. However, the decrease of fractional oscillation amplitude with rise time, which provides a main observational support for the flame spreading model, have so far been reported from only a few bursts. Moreover, the non-detection and intermittent detections of rise oscillations from many bursts are not yet understood considering the flame spreading scenario. Here, we report the decreasing trend of fractional oscillation amplitude from an extensive analysis of a large sample of Rossi X-ray Timing Explorer Proportional Counter Array bursts from ten neutron star low-mass X-ray binaries. This trend is 99.99% significant for the best case, which provides, to the best of our knowledge, by far the strongest evidence of such trend. Moreover, it is important to note that an opposite trend is not found from any of the bursts. The concave shape of the fractional ampli...

Chakraborty, Manoneeta

2014-01-01T23:59:59.000Z

435

Rotational effects in thermonuclear Type I Bursts: equatorial crossing and directionality of flame spreading  

E-Print Network [OSTI]

In a previous study on thermonuclear (Type I) Bursts on accreting neutron stars we addressed and demonstrated the importance of the effects of rotation, through the Coriolis force, on the propagation of the burning flame. However, that study only analysed cases of longitudinal propagation, where the Coriolis force coefficient $2\\Omega\\cos\\theta$ was constant. In this paper, we study the effects of rotation on propagation in the meridional (latitudinal) direction, where the Coriolis force changes from its maximum at the poles to zero at the equator. We find that the zero Coriolis force at the equator, while affecting the structure of the flame, does not prevent its propagation from one hemisphere to another. We also observe structural differences between the flame propagating towards the equator and that propagating towards the pole, the second being faster. In the light of the recent discovery of the low spin frequency of burster IGR~J17480-2446 rotating at 11 Hz (for which Coriolis effects should be negligib...

Cavecchi, Yuri; Levin, Yuri; Braithwaite, Jonathan

2014-01-01T23:59:59.000Z

436

On the applicability of the level set method beyond the flamelet regime in thermonuclear supernova simulations  

E-Print Network [OSTI]

In thermonuclear supernovae, intermediate mass elements are mostly produced by distributed burning provided that a deflagration to detonation transition does not set in. Apart from the two-dimensional study by Roepke & Hillebrandt (2005), very little attention has been payed so far to the correct treatment of this burning regime in numerical simulations. In this article, the physics of distributed burning is reviewed from the literature on terrestrial combustion and differences which arise from the very small Prandtl numbers encountered in degenerate matter are pointed out. Then it is shown that the level set method continues to be applicable beyond the flamelet regime as long as the width of the flame brush does not become smaller than the numerical cutoff length. Implementing this constraint with a simple parameterisation of the effect of turbulence onto the energy generation rate, the production of intermediate mass elements increases substantially compared to previous simulations, in which the burning process was stopped once the mass density dropped below 10^7 g/cm^3. Although these results depend on the chosen numerical resolution, an improvement of the constraints on the the total mass of burning products in the pure deflagration scenario can be achieved.

W. Schmidt

2007-01-15T23:59:59.000Z

437

Double-peaked thermonuclear bursts at the soft-hard state transition in the Rapid Burster  

E-Print Network [OSTI]

Long suspected to be due to unstable accretion events, the type II bursts exhibited by the Rapid Burster (RB, or MXB 1730-335) still lack an exhaustive explanation. Apart from type II bursts, the transient RB also shows the better-understood thermonuclear shell flashes known as type I bursts. In search of links between these two phenomena, we carried out a comprehensive analysis of all $\\textit{Rossi X-ray Timing Explorer}$ observations of the RB and found six atypical type I bursts, featuring a double-peaked profile that is not due to photospheric radius expansion. The bursts appear in a phase of the outburst decay close to the onset of the type II bursts, when the source also switches from the high/soft to the low/hard state. We also report the discovery of a simultaneous low-frequency quasi-periodic oscillation present in the persistent emission as well as in the burst decaying emission. We discuss several scenarios to understand the nature of the peculiar bursts and of the accompanying oscillation, as wel...

Bagnoli, T; Patruno, A; Watts, A L

2013-01-01T23:59:59.000Z

438

Relics of metal-free low mass stars exploding as thermonuclear supernovae  

E-Print Network [OSTI]

Renewed interest in the first stars that were formed in the universe has led to the discovery of extremely iron-poor stars. Since several competing scenarios exist, our understanding of the mass range that determines the observed elemental abundances remains unclear. In this study, we consider three well-studied metal-poor stars in terms of the theoretical supernovae (SNe) model. Our results suggest that the observed abundance patterns in the metal-poor star BD +80 245 and the pair of stars HD 134439/40 agree strongly with the theoretical possibility that these stars inherited their heavy element abundance patterns from SNe initiated by thermonuclear runaways in the degenerate carbon-oxygen cores of primordial asymptotic giant branch stars with \\~3.5-5 solar masses. Recent theoretical calculations have predicted that such SNe could be originated from metal-free stars in the intermediate mass range. On the other hand, intermediate mass stars containing some metals would end their lives as white dwarfs after ex...

Tsujimoto, T; Tsujimoto, Takuji; Shigeyama, Toshikazu

2006-01-01T23:59:59.000Z

439

Frontier of Fusion Research: Path to the Steady State Fusion Reactor by Large Helical Device  

SciTech Connect (OSTI)

The ITER, the International Thermonuclear Experimental Reactor, which will be built in Cadarache in France, has finally started this year, 2006. Since the thermal energy produced by fusion reactions divided by the external heating power, i.e., the Q value, will be larger than 10, this is a big step of the fusion research for half a century trying to tame the nuclear fusion for the 6.5 Billion people on the Earth. The source of the Sun's power is lasting steadily and safely for 8 Billion years. As a potentially safe environmentally friendly and economically competitive energy source, fusion should provide a sustainable future energy supply for all mankind for ten thousands of years. At the frontier of fusion research important milestones are recently marked on a long road toward a true prototype fusion reactor. In its own merits, research into harnessing turbulent burning plasmas and thereby controlling fusion reaction, is one of the grand challenges of complex systems science.After a brief overview of a status of world fusion projects, a focus is given on fusion research at the National Institute for Fusion Science (NIFS) in Japan, which is playing a role of the Inter University Institute, the coordinating Center of Excellence for academic fusion research and by the Large Helical Device (LHD), the world's largest superconducting heliotron device, as a National Users' facility. The current status of LHD project is presented focusing on the experimental program and the recent achievements in basic parameters and in steady state operations. Since, its start in a year 1998, a remarkable progress has presently resulted in the temperature of 140 Million degree, the highest density of 500 Thousand Billion/cc with the internal density barrier (IDB) and the highest steady average beta of 4.5% in helical plasma devices and the largest total input energy of 1.6 GJ, in all magnetic confinement fusion devices. Finally, a perspective is given of the ITER Broad Approach program as an integrated part of ITER and Development of Fusion Energy project Agreement. Moreover, the relationship with the NIFS' new parent organization the National Institutes of Natural Sciences and with foreign research institutions is briefly explained.

Motojima, Osamu [National Institute for Fusion Science, Toki-shi, Gifu-ken, 509-5292 (Japan)

2006-12-01T23:59:59.000Z

440

Reactor Engineering: Experimental Investigation of Alpha Convection  

SciTech Connect (OSTI)

Natural convection, Rayleigh-Bernard convection, Transient convection and Conduction convection transition.

Usman, Shoaib

2012-10-12T23:59:59.000Z

Note: This page contains sample records for the topic "thermonuclear experimental reactor" from the National Library of EnergyBeta (NLEBeta).
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441

Sandia National Laboratories: International Tokamak Experimental Reactor  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -theErik Spoerke SSLS Exhibit atVehicleEnergyPolydotsMicro

442

Recent results and challenges in development of metallic Hall sensors for fusion reactors  

SciTech Connect (OSTI)

Reliable and precise diagnostic of local magnetic field is crucial for successful operation of future thermonuclear fusion reactors based on magnetic confinement. Magnetic sensors at these devices will experience an extremely demanding operational environment with large radiation and thermal loads in combination with required long term, reliable, and service-free performance. Neither present day commercial nor laboratory measurement systems comply with these requirements. Metallic Hall sensors based on e.g. copper or bismuth could potentially satisfy these needs. We present the technology for manufacturing of such sensors and some initial results on characterization of their properties.

?uran, Ivan; Mušálek, Radek; Kova?ík, Karel [Institute of Plasma Physics AS CR, Za Slovankou 3, 182 00 Praha 8 (Czech Republic); Sentkerestiová, Jana [Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, B?ehová 7, 115 19 Praha 1 (Czech Republic); Kohout, Michal [Institute of Physics AS CR, Na Slovance 1999/2, 182 21 Praha 8 (Czech Republic); Viererbl, Ladislav [Research Centre Rez, Hlavní 130, 250 68 Husinec-?ež (Czech Republic)

2014-08-21T23:59:59.000Z

443

Reactor D and D at Argonne National Laboratory - lessons learned.  

SciTech Connect (OSTI)

This paper focuses on the lessons learned during the decontamination and decommissioning (D and D) of two reactors at Argonne National Laboratory-East (ANL-E). The Experimental Boiling Water Reactor (EBWR) was a 100 MW(t), 5 MSV(e) proof-of-concept facility. The Janus Reactor was a 200 kW(t) reactor located at the Biological Irradiation Facility and was used to study the effects of neutron radiation on animals.

Fellhauer, C. R.

1998-03-23T23:59:59.000Z

444

Reference worldwide model for antineutrinos from reactors  

E-Print Network [OSTI]

Antineutrinos produced at nuclear reactors constitute a severe source of background for the detection of geoneutrinos, which bring to the Earth's surface information about natural radioactivity in the whole planet. In this framework we provide a reference worldwide model for antineutrinos from reactors, in view of reactors operational records yearly published by the International Atomic Energy Agency (IAEA). We evaluate the expected signal from commercial reactors for ongoing (KamLAND and Borexino), planned (SNO+) and proposed (Juno, RENO-50, LENA and Hanohano) experimental sites. Uncertainties related to reactor antineutrino production, propagation and detection processes are estimated using a Monte Carlo based approach, which provides an overall site dependent uncertainty on the signal in the geoneutrino energy window on the order of 3%. We also implement the off-equilibrium correction to the reference reactor spectra associated with the long-lived isotopes and we estimate a 2.4% increase of the unoscillated event rate in the geoneutrino energy window due to the storage of spent nuclear fuels in the cooling pools. We predict that the research reactors contribute to less than 0.2% to the commercial reactor signal in the investigated 14 sites. We perform a multitemporal analysis of the expected reactor signal over a time lapse of 10 years using reactor operational records collected in a comprehensive database published at www.fe.infn.it/antineutrino.

Marica Baldoncini; Ivan Callegari; Giovanni Fiorentini; Fabio Mantovani; Barbara Ricci; Virginia Strati; Gerti Xhixha

2015-02-16T23:59:59.000Z

445

Charged-Particle Thermonuclear Reaction Rates: I. Monte Carlo Method and Statistical Distributions  

E-Print Network [OSTI]

A method based on Monte Carlo techniques is presented for evaluating thermonuclear reaction rates. We begin by reviewing commonly applied procedures and point out that reaction rates that have been reported up to now in the literature have no rigorous statistical meaning. Subsequently, we associate each nuclear physics quantity entering in the calculation of reaction rates with a specific probability density function, including Gaussian, lognormal and chi-squared distributions. Based on these probability density functions the total reaction rate is randomly sampled many times until the required statistical precision is achieved. This procedure results in a median (Monte Carlo) rate which agrees under certain conditions with the commonly reported recommended "classical" rate. In addition, we present at each temperature a low rate and a high rate, corresponding to the 0.16 and 0.84 quantiles of the cumulative reaction rate distribution. These quantities are in general different from the statistically meaningless "minimum" (or "lower limit") and "maximum" (or "upper limit") reaction rates which are commonly reported. Furthermore, we approximate the output reaction rate probability density function by a lognormal distribution and present, at each temperature, the lognormal parameters miu and sigma. The values of these quantities will be crucial for future Monte Carlo nucleosynthesis studies. Our new reaction rates, appropriate for bare nuclei in the laboratory, are tabulated in the second paper of this series (Paper II). The nuclear physics input used to derive our reaction rates is presented in the third paper of this series (Paper III). In the fourth paper of this series (Paper IV) we compare our new reaction rates to previous results.

Richard Longland; Christian Iliadis; Art Champagne; Joe Newton; Claudio Ugalde; Alain Coc; Ryan Fitzgerald

2010-04-23T23:59:59.000Z

446

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

447

THE FERMI-GBM X-RAY BURST MONITOR: THERMONUCLEAR BURSTS FROM 4U 0614+09  

SciTech Connect (OSTI)

Thermonuclear bursts from slowly accreting neutron stars (NSs) have proven difficult to detect, yet they are potential probes of the thermal properties of the NS interior. During the first year of a systematic all-sky search for X-ray bursts using the Gamma-ray Burst Monitor aboard the Fermi Gamma-ray Space Telescope we have detected 15 thermonuclear bursts from the NS low-mass X-ray binary 4U 0614+09 when it was accreting at nearly 1% of the Eddington limit. We measured an average burst recurrence time of 12 {+-} 3 days (68% confidence interval) between 2010 March and 2011 March, classified all bursts as normal duration bursts and placed a lower limit on the recurrence time of long/intermediate bursts of 62 days (95% confidence level). We discuss how observations of thermonuclear bursts in the hard X-ray band compare to pointed soft X-ray observations and quantify such bandpass effects on measurements of burst radiated energy and duration. We put our results for 4U 0614+09 in the context of other bursters and briefly discuss the constraints on ignition models. Interestingly, we find that the burst energies in 4U 0614+09 are on average between those of normal duration bursts and those measured in long/intermediate bursts. Such a continuous distribution in burst energy provides a new observational link between normal and long/intermediate bursts. We suggest that the apparent bimodal distribution that defined normal and long/intermediate duration bursts during the last decade could be due to an observational bias toward detecting only the longest and most energetic bursts from slowly accreting NSs.

Linares, M.; Chakrabarty, D. [Massachusetts Institute of Technology, Kavli Institute for Astrophysics and Space Research, Cambridge, MA 02139 (United States); Connaughton, V.; Bhat, P. N.; Briggs, M. S.; Preece, R. [CSPAR and Physics Department, University of Alabama in Huntsville, Huntsville, AL 35899 (United States); Jenke, P.; Kouveliotou, C.; Wilson-Hodge, C. A. [Space Science Office, VP62, NASA/Marshall Space Flight Center, Huntsville, AL 35812 (United States); Van der Horst, A. J. [Astronomical Institute 'Anton Pannekoek', University of Amsterdam, NL-1090-GE Amsterdam (Netherlands); Camero-Arranz, A.; Finger, M.; Paciesas, W. S. [Universities Space Research Association, Huntsville, AL 35805 (United States); Beklen, E. [Physics Department, Suleyman Demirel University, 32260 Isparta (Turkey); Von Kienlin, A. [Max Planck Institute for Extraterrestrial Physics, Giessenbachstrasse, Postfach 1312, D-85748 Garching (Germany)

2012-12-01T23:59:59.000Z

448

Parametic Study of the current limit within a single driver-scale transport beam line of an induction Linac for Heavy Ion Fusion  

E-Print Network [OSTI]

for a Power Producing Thermonuclear Reactor, in Proceedingsorder for significant thermonuclear energy production, thethe approach to controlled thermonuclear fusion which uses

Prost, Lionel Robert

2007-01-01T23:59:59.000Z

449

Nuclear reactor engineering  

SciTech Connect (OSTI)

A book is reviewed which emphasizes topics directly related to the light water reactor power plant and the fast reactor power system. Current real-world problems are addressed throughout the text, and a chapter on safety includes much of the postThree Mile Island impact on operating systems. Topics covered include Doppler broadening, neutron resonances, multigroup diffusion theory, reactor kinetics, reactor control, energy removal, nonfuel materials, reactor fuel, radiation protection, environmental effects, and reactor safety.

Glasstone, S.; Sesonske, A.

1982-07-01T23:59:59.000Z

450

BURN CONTROL IN FUSION REACTORS VIA NONLINEAR STABILIZATION TECHNIQUES  

E-Print Network [OSTI]

of low temperature and high density where the thermonuclear reaction is inherently thermally unstable. Figure 1a shows that for low temperatures the rate of thermonuclear reaction for a D-T mixture in stabilization of the thermonuclear reaction can be obtained. Neverthe- less, this approach is often insufficient

Krstic, Miroslav

451

Accelerators for Subcritical Molten-Salt Reactors  

SciTech Connect (OSTI)

Accelerator parameters for subcritical reactors have usually been based on using solid nuclear fuel much like that used in all operating critical reactors as well as the thorium burning accelerator-driven energy amplifier proposed by Rubbia et al. An attractive alternative reactor design that used molten salt fuel was experimentally studied at ORNL in the 1960s, where a critical molten salt reactor was successfully operated using enriched U235 or U233 tetrafluoride fuels. These experiments give confidence that an accelerator-driven subcritical molten salt reactor will work better than conventional reactors, having better efficiency due to their higher operating temperature, having the inherent safety of subcritical operation, and having constant purging of volatile radioactive elements to eliminate their accumulation and potential accidental release in dangerous amounts. Moreover, the requirements to drive a molten salt reactor can be considerably relaxed compared to a solid fuel reactor, especially regarding accelerator reliability and spallation neutron targetry, to the point that much of the required technology exists today. It is proposed that Project-X be developed into a prototype commercial machine to produce energy for the world by, for example, burning thorium in India and nuclear waste from conventional reactors in the USA.

Johnson, Roland (Muons, Inc.) [Muons, Inc.

2011-08-03T23:59:59.000Z

452

The Effects of Variations in Nuclear Interactions on Nucleosynthesis in Thermonuclear Supernovae  

E-Print Network [OSTI]

The impact of nuclear physics uncertainties on nucleosynthesis in thermonuclear supernovae has not been fully explored using comprehensive and systematic studies with multiple models. To better constrain predictions of yields from these phenomena, we have performed a sensitivity study by post-processing thermodynamic histories from two different hydrodynamic, Chandrasekhar-mass explosion models. We have individually varied all input reaction and, for the first time, weak interaction rates by a factor of ten and compared the yields in each case to yields using standard rates. Of the 2305 nuclear reactions in our network, we find that the rates of only 53 reactions affect the yield of any species with an abundance of at least 10^-8 M_sun by at least a factor of two, in either model. The rates of the 12C(a,g), 12C+12C, 20Ne(a,p), 20Ne(a,g) and 30Si(p,g) reactions are among those that modify the most yields when varied by a factor of ten. From the individual variation of 658 weak interaction rates in our network by a factor of ten, only the stellar 28Si(b+)28Al, 32S(b+)32P and 36Ar(b+)36Cl rates significantly affect the yields of species in a model. Additional tests reveal that reaction rate changes over temperatures T > 1.5 GK have the greatest impact, and that ratios of radionuclides that may be used as explosion diagnostics change by a factor of less than two from the variation of individual rates by a factor of 10. Nucleosynthesis in the two adopted models is relatively robust to variations in individual nuclear reaction and weak interaction rates. Laboratory measurements of a limited number of reactions would help to further constrain predictions. As well, we confirm the need for a consistent treatment for relevant stellar weak interaction rates since simultaneous variation of these rates (as opposed to individual variation) has a significant effect on yields in our models.

Anuj Parikh; Jordi Jose; Ivo R. Seitenzahl; Friedrich K. Roepke

2013-06-25T23:59:59.000Z

453

JOURNAL DE PHYSIQUE Colloque C1, supplkment au no2, Tome 40,fkvr~er1979, page C1-73 ATOMIC, IONIC AND MOLECULAR DATA IN THERMO-NUCLEAR FUSION RESEARCH  

E-Print Network [OSTI]

AND MOLECULAR DATA IN THERMO-NUCLEAR FUSION RESEARCH H.W. Drawin Association EURATOM-CEA DQpartement de Physique section deals with molecular data which are of interest in thermo-nuclear fusion research. 1. INTRODUCTION In order to achieve controlled thermo- nuclear fusion of deuterium and tritium one needs both high

Paris-Sud XI, Université de

454

On the Frequency Evolution of X-ray Brightness Oscillations During Thermonuclear X-ray Bursts: Evidence for Coherent Oscillations  

E-Print Network [OSTI]

We investigate the time dependence of the frequency of X-ray brightness oscillations during thermonuclear bursts from several neutron star low mass X-ray binaries. We find that the oscillation frequencies in the cooling tails of X-ray bursts from 4U 1702-429 and 4U 1728-34 are well described by an exponential "chirp" model. With this model we demonstrate that the pulse trains in the cooling tails of many bursts are highly phase coherent, having oscillation quality factors as high as Q ~ 4000. We use this model of the frequency evolution to search sensitively for significant power at the harmonics and first sub-harmonic of the 330 and 363 Hz signals in bursts from 4U 1702-429 and 4U 1728-34, respectively, but find not evidence for significant power at any harmonic or the sub-harmonic. We argue that the high coherence favors stellar rotation as the source of the oscillations. We briefly discuss the frequency evolution in terms of rotational motion of an angular momentum conserving thermonuclear shell. we discuss how the limits on harmonic content can be used to infer properties of the neutron star.

Tod E. Strohmayer; Craig B. Markwardt

1999-03-03T23:59:59.000Z

455

Comparison of the recently proposed super-Marx generator approach to thermonuclear ignition with the deuterium-tritium laser fusion-fission hybrid concept by the Lawrence Livermore National Laboratory  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

The recently proposed super-Marx generator pure deuterium microdetonation ignition concept is compared to the Lawrence Livermore National Ignition Facility (NIF) Laser deuterium-tritium fusion-fission hybrid concept (LIFE). In a super-Marx generator, a large number of ordinary Marx generators charge up a much larger second stage ultrahigh voltage Marx generator from which for the ignition of a pure deuterium microexplosion an intense GeV ion beam can be extracted. Typical examples of the LIFE concept are a fusion gain of 30 and a fission gain of 10, making up a total gain of 300, with about ten times more energy released into fission as compared to fusion. This means the substantial release of fission products, as in fissionless pure fission reactors. In the super-Marx approach for the ignition of pure deuterium microdetonation, a gain of the same magnitude can, in theory, be reached. If feasible, the super-Marx generator deuterium ignition approach would make lasers obsolete as a means for the ignition of thermonuclear microexplosions.

Winterberg, F.

2009-10-29T23:59:59.000Z

456

Photoneutron effects on pulse reactor kinetics for the Annular Core Research Reactor (ACRR).  

SciTech Connect (OSTI)

The Annular Core Research Reactor (ACRR) is a swimming-pool type pulsed reactor that maintains an epithermal neutron flux and a nine-inch diameter central dry cavity. One of its uses is neutron and gamma-ray irradiation damage studies on electronic components under transient reactor power conditions. In analyzing the experimental results, careful attention must be paid to the kinetics associated with the reactor to ensure that the transient behavior of the electronic device is understood. Since the ACRR fuel maintains a substantial amount of beryllium, copious quantities of photoneutrons are produced that can significantly alter the expected behavior of the reactor power, especially following a reactor pulse. In order to understand these photoneutron effects on the reactor kinetics, the KIFLE transient reactor-analysis code was modified to include the photoneutron groups associated with the beryllium. The time-dependent behavior of the reactor power was analyzed for small and large pulses, assuming several initial conditions including following several pulses during the day, and following a long steady-state power run. The results indicate that, for these types of initial conditions, the photoneutron contribution to the reactor pulse energy can have a few to tens of percent effect.

Parma, Edward J., Jr.

2009-06-01T23:59:59.000Z

457

Reactor safety method  

DOE Patents [OSTI]

This invention relates to safety means for preventing a gas cooled nuclear reactor from attaining criticality prior to start up in the event the reactor core is immersed in hydrogenous liquid. This is accomplished by coating the inside surface of the reactor coolant channels with a neutral absorbing material that will vaporize at the reactor's operating temperature.

Vachon, Lawrence J. (Clairton, PA)

1980-03-11T23:59:59.000Z

458

SRS Small Modular Reactors  

SciTech Connect (OSTI)

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

None

2012-04-27T23:59:59.000Z

459

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

460

Laser or charged-particle-beam fusion reactor with direct electric generation by magnetic flux compression  

DOE Patents [OSTI]

The invention is a laser or particle-beam-driven fusion reactor system which takes maximum advantage of both the very short pulsed nature of the energy release of inertial confinement fusion (ICF) and the very small volumes within which the thermonuclear burn takes place. The pulsed nature of ICF permits dynamic direct energy conversion schemes such as magnetohydrodynamic (MHD) generation and magnetic flux compression; the small volumes permit very compact blanket geometries. By fully exploiting these characteristics of ICF, it is possible to design a fusion reactor with exceptionally high power density, high net electric efficiency, and low neutron-induced radioactivity. The invention includes a compact blanket design and method and apparatus for obtaining energy utilizing the compact blanket.

Lasche, G.P.

1983-09-29T23:59:59.000Z

Note: This page contains sample records for the topic "thermonuclear experimental 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.


461

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

462

On the Effect of Explosive Thermonuclear Burning on the Accreted Envelopes of White Dwarfs in Cataclysmic Variables  

E-Print Network [OSTI]

The detection of heavy elements at suprasolar abundances in the atmospheres of some accreting white dwarfs in cataclysmic variables, coupled with the high temperatures needed to produce these elements requires explosive thermonuclear burning. The central temperatures of any formerly more massive secondary stars in CVs undergoing hydrostatic CNO burning are far too low to produce these elements. Evidence is presented that at least some cataclysmic variables contain donor secondaries that have been contaminated by repeated novae ejecta and are transferring this material back to the white dwarf. This scenario does not exclude the channel in which formerly more massive donor stars underwent CNO processing in ystems that underwent thermal timescale mass transfer. Implications for the progenitors of CVs are discussed.

Sion, Edward M

2014-01-01T23:59:59.000Z

463

Modeling for Anaerobic Fixed-Bed Biofilm Reactors  

SciTech Connect (OSTI)

The specific objectives of this research were: 1. to develop an equilibrium model for chemical aspects of anaerobic reactors; 2. to modify the equilibrium model for non-equilibrium conditions; 3. to incorporate the existing biofilm models into the models above to study the biological and chemical behavior of the fixed-film anaerobic reactors; 4. to experimentally verify the validity of these models; 5. to investigate the biomass-holding ability of difference packing materials for establishing reactor design criteria.

Liu, B. Y. M.; Pfeffer, J. T.

1989-06-01T23:59:59.000Z

464

Nuclear reactors built, being built, or planned, 1991  

SciTech Connect (OSTI)

This document contains unclassified information about facilities built, being built, or planned in the United States for domestic use or export as of December 31, 1991. The book is divided into three major sections: Section 1 consists of a reactor locator map and reactor tables; Section 2 includes nuclear reactors that are operating, being built, or planned; and Section 3 includes reactors that have been shut down permanently or dismantled. Sections 2 and 3 contain the following classification of reactors: Civilian, Production, Military, Export, and Critical Assembly. Export reactor refers to a reactor for which the principal nuclear contractor is an American company -- working either independently or in cooperation with a foreign company (Part 4, in each section). Critical assembly refers to an assembly of fuel and assembly of fuel and moderator that requires an external source of neutrons to initiate and maintain fission. A critical assembly is used for experimental measurements (Part 5).

Simpson, B.

1992-07-01T23:59:59.000Z

465

Two days of negotiations in  

E-Print Network [OSTI]

France or Japan would host the revolutionary International Thermonuclear Experimental Reactor (ITER to secure an agreement on whether France or Japan would host the revolutionary International Thermonuclear, deputy director of Japan's Office of Fusion Energy, told AFP. "What we have proposed is that the host

466

Deadlock in ITER talks must end Tatsuo Nakajima Yomiuri Shimbun Staff Writer  

E-Print Network [OSTI]

Japan and the European Union over where to construct the International Thermonuclear Experimental flights home, leaving before those in attendance were able to schedule the next meeting. A thermonuclear fusion, which is more efficient than nuclear fission reactors. In what will be the world's first

467

ITER site contest counts down Junichi Miura  

E-Print Network [OSTI]

Thermonuclear Experimental Reactor (ITER), an international project to use nuclear fusion energy for electric on a site for the project. The ITER project envisions using thermonuclear fusion to generate huge amounts heavy hydrogen and tritium used for fuel in the fusion reaction are heated in a vacuum receptacle at 100

468

Course: FUSION SCIENCE AND ENGINEERING Universit degli Studi di Padova  

E-Print Network [OSTI]

the subject of controlled thermonuclear fusion in magnetically confined plasmas. Both fusion science of Controlled Thermonuclear Fusion, b) Engineering of a Magnetically Confined Fusion Reactor, c) ExperimentalCourse: FUSION SCIENCE AND ENGINEERING Università degli Studi di Padova in agreement

Cesare, Bernardo

469

---Home Yahoo! Help My Yahoo! http://asia.news.yahoo.com/041111/kyodo/d869foe00.html  

E-Print Network [OSTI]

Thermonuclear Experimental Reactor to Aomori Prefecture. "The Japanese business community should be united with the European Union, the United States, Russia, China and South Korea in the thermonuclear project to create the world's first sustained nuclear fusion reaction, similar to the energy- producing process that takes

470

Development of an experiment to study the effects of transverse stress on the critical current of a niobium-tin superconducting cable  

E-Print Network [OSTI]

Superconducting magnets will play a central role for the success of the International Thermonuclear Experimental Reactor (ITER). ITER is a current driven plasma experiment that could set a milestone towards the demonstration ...

Chiesa, Luisa

2006-01-01T23:59:59.000Z

471

PERFORMANCE BOUNDARIES IN Nb3Sn SUPERCONDUCTORS  

E-Print Network [OSTI]

of Wisconsin-Madison, USA. This work was supported by the European Union through the European Fusion for the International Thermonuclear Experimental Reactor. Part of the task description was to summarize the results

472

E-Print Network 3.0 - advanced superconducting tokamak Sample...  

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

Fusion 3 03012006 09:51 AMLoading "People's Daily Online --Chinese experimental thermonuclear reactor on discharge test in July" Page 1 of 1http:english.people.com.cn200603...

473

E-Print Network 3.0 - advanced tokamaks final Sample Search Results  

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

Fusion 10 03012006 09:51 AMLoading "People's Daily Online --Chinese experimental thermonuclear reactor on discharge test in July" Page 1 of 1http:english.people.com.cn200603...

474

E-Print Network 3.0 - advanced tokamak discharges Sample Search...  

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

Fusion 3 03012006 09:51 AMLoading "People's Daily Online --Chinese experimental thermonuclear reactor on discharge test in July" Page 1 of 1http:english.people.com.cn200603...

475

Undergraduate reactor control experiment  

SciTech Connect (OSTI)

A sequence of reactor and related experiments has been a central element of a senior-level laboratory course at Pennsylvania State University (Penn State) for more than 20 yr. A new experiment has been developed where the students program and operate a computer controller that manipulates the speed of a secondary control rod to regulate TRIGA reactor power. Elementary feedback control theory is introduced to explain the experiment, which emphasizes the nonlinear aspect of reactor control where power level changes are equivalent to a change in control loop gain. Digital control of nuclear reactors has become more visible at Penn State with the replacement of the original analog-based TRIGA reactor control console with a modern computer-based digital control console. Several TRIGA reactor dynamics experiments, which comprise half of the three-credit laboratory course, lead to the control experiment finale: (a) digital simulation, (b) control rod calibration, (c) reactor pulsing, (d) reactivity oscillator, and (e) reactor noise.

Edwards, R.M.; Power, M.A.; Bryan, M. (Pennsylvania State Univ., University Park (United States))

1992-01-01T23:59:59.000Z

476

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.

Scott, Charles D. (Oak Ridge, TN); Davison, Brian H. (Knoxvile, TN)

1993-01-01T23:59:59.000Z

477

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

478

Reactor Sharing Program  

SciTech Connect (OSTI)

Progress achieved at the University of Florida Training Reactor (UFTR) facility through the US Department of Energy's University Reactor Sharing Program is reported for the period of 1991--1992.

Vernetson, W.G.

1993-01-01T23:59:59.000Z

479

POTENTIAL BENCHMARKS FOR ACTINIDE PRODUCTION IN HANFORD REACTORS  

SciTech Connect (OSTI)

A significant experimental program was conducted in the early Hanford reactors to understand the reactor production of actinides. These experiments were conducted with sufficient rigor, in some cases, to provide useful information that can be utilized today in development of benchmark experiments that may be used for the validation of present computer codes for the production of these actinides in low enriched uranium fuel.

PUIGH RJ; TOFFER H

2011-10-19T23:59:59.000Z

480

Reactor materials study of EBR-II and BN350  

E-Print Network [OSTI]

The objective of this research is to go through the technical review of how the body of information relating to the in-reactor behavior of structural materials of Experimental Breeder Reactor-II (EBR-II) and BN350 are associated. Such an effort...

Yilmaz, Fatma

2002-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "thermonuclear experimental 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.


481

High solids fermentation reactor  

DOE Patents [OSTI]

A fermentation reactor and method for fermentation of materials having greater than about 10% solids. The reactor includes a rotatable shaft along the central axis, the shaft including rods extending outwardly to mix the materials. The reactor and method are useful for anaerobic digestion of municipal solid wastes to produce methane, for production of commodity chemicals from organic materials, and for microbial fermentation processes.

Wyman, Charles E.; Grohmann, Karel; Himmel, Michael E.; Richard, Christopher J.

1993-03-02T23:59:59.000Z

482

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

483

Advanced Test Reactor Tour  

SciTech Connect (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

2011-01-01T23:59:59.000Z

484

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

485

High solids fermentation reactor  

DOE Patents [OSTI]

A fermentation reactor and method for fermentation of materials having greater than about 10% solids. The reactor includes a rotatable shaft along the central axis, the shaft including rods extending outwardly to mix the materials. The reactor and method are useful for anaerobic digestion of municipal solid wastes to produce methane, for production of commodity chemicals from organic materials, and for microbial fermentation processes.

Wyman, Charles E. (Lakewood, CO); Grohmann, Karel (Littleton, CO); Himmel, Michael E. (Littleton, CO); Richard, Christopher J. (Lakewood, CO)

1993-01-01T23:59:59.000Z

486

Hypothetical Reactor Accident Study  

E-Print Network [OSTI]

- W 4 DfcSkoollo Rise-R-427 CARNSORE: Hypothetical Reactor Accident Study O. Walmod-Larsen, N. O: HYPOTHETICAL REACTOR ACCIDENT STUDY O. Walmod-Larsen, N.O. Jensen, L. Kristensen, A. Heide, K.L. Nedergård, P-basis accident and a series of hypothetical core-melt accidents to a 600 MWe reactor are de- scribed

487

Advanced Computational Thermal Fluid Physics (CTFP) and Its Assessment for Light Water Reactors and Supercritical Reactors  

SciTech Connect (OSTI)

Background: The ultimate goal of the study is the improvement of predictive methods for safety analyses and design of Generation IV reactor systems such as supercritical water reactors (SCWR) for higher efficiency, improved performance and operation, design simplification, enhanced safety and reduced waste and cost. The objective of this Korean / US / laboratory / university collaboration of coupled fundamental computational and experimental studies is to develop the supporting knowledge needed for improved predictive techniques for use in the technology development of Generation IV reactor concepts and their passive safety systems. The present study emphasizes SCWR concepts in the Generation IV program.

D.M. McEligot; K. G. Condie; G. E. McCreery; H. M. McIlroy; R. J. Pink; L.E. Hochreiter; J.D. Jackson; R.H. Pletcher; B.L. Smith; P. Vukoslavcevic; J.M. Wallace; J.Y. Yoo; J.S. Lee; S.T. Ro; S.O. Park

2005-10-01T23:59:59.000Z

488

Experimental Neutrino Physics: Final Report  

SciTech Connect (OSTI)

Experimental studies of neutrino properties, with particular emphasis on neutrino oscillation, mass and mixing parameters. This research was pursued by means of underground detectors for reactor anti-neutrinos, measuring the flux and energy spectra of the neutrinos. More recent investigations have been aimed and developing detector technologies for a long-baseline neutrino experiment (LBNE) using a neutrino beam from Fermilab.

Lane, Charles E.; Maricic, Jelena

2012-09-05T23:59:59.000Z

489

Neutron behavior, reactor control, and reactor heat transfer. Volume four  

SciTech Connect (OSTI)

Volume four covers neutron behavior (neutron absorption, how big are nuclei, neutron slowing down, neutron losses, the self-sustaining reactor), reactor control (what is controlled in a reactor, controlling neutron population, is it easy to control a reactor, range of reactor control, what happens when the fuel burns up, controlling a PWR, controlling a BWR, inherent safety of reactors), and reactor heat transfer (heat generation in a nuclear reactor, how is heat removed from a reactor core, heat transfer rate, heat transfer properties of the reactor coolant).

Not Available

1986-01-01T23:59:59.000Z

490

Stress Management as an Enabling Technology for High-Field Superconducting Dipole Magnets  

E-Print Network [OSTI]

-Pounds HD High field Dipole HGQ High Gradient Quadrupole HQ High field Quadrupole HT Heat Treatment IC Critical Current IFCC Inter-Filament Coupling Currents ITER International Thermonuclear Experimental Reactor vi LARP LHC Accelerator... pressure impregnation (VPI) vessel using NbTi conductor [1, 2]. TAMU2 verified the heat treatment equipment and tested the stress management technology at low field using low Jc Nb3Sn conductor from the International Thermonuclear Experimental Reactor...

Holik, Eddie Frank

2014-06-03T23:59:59.000Z

491

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

492

OPTIMAL DESIGN OF A HIGH PRESSURE ORGANOMETALLIC CHEMICAL VAPOR DEPOSITION REACTOR  

E-Print Network [OSTI]

OPTIMAL DESIGN OF A HIGH PRESSURE ORGANOMETALLIC CHEMICAL VAPOR DEPOSITION REACTOR K.J. BACHMANN of computer simulations as an optimal design tool which lessens the costs in time and effort in experimental vapor deposition (HPOMCVD) reactor for use in thin film crystal growth. The advantages of such a reactor

493

CAD Technique for Microwave Chemistry Reactors with Energy Efficiency Optimized for Different Reactants  

E-Print Network [OSTI]

CAD Technique for Microwave Chemistry Reactors with Energy Efficiency Optimized for Different in experimental development of large- scale and highly-productive reactors. This paper proposes to address this issue by developing microwave chemistry reactors as microwave systems, rather than as black

Yakovlev, Vadim

494

Department of Earth and Mineral Engineering Spring 2011 Oxidative Coupling of Methane Reactor  

E-Print Network [OSTI]

PENNSTATE Department of Earth and Mineral Engineering Spring 2011 Oxidative Coupling of Methane of an experimental reactor designed to couple methane to ethane and dehydrogenate ethane to ethylene. The reactor and build the reactor and perform methane conversion testing to provide proof of concept for the OCM

Demirel, Melik C.

495

Spinning fluids reactor  

DOE Patents [OSTI]

A spinning fluids reactor, includes a reactor body (24) having a circular cross-section and a fluid contactor screen (26) within the reactor body (24). The fluid contactor screen (26) having a plurality of apertures and a circular cross-section concentric with the reactor body (24) for a length thus forming an inner volume (28) bound by the fluid contactor screen (26) and an outer volume (30) bound by the reactor body (24) and the fluid contactor screen (26). A primary inlet (20) can be operatively connected to the reactor body (24) and can be configured to produce flow-through first spinning flow of a first fluid within the inner volume (28). A secondary inlet (22) can similarly be operatively connected to the reactor body (24) and can be configured to produce a second flow of a second fluid within the outer volume (30) which is optionally spinning.

Miller, Jan D; Hupka, Jan; Aranowski, Robert

2012-11-20T23:59:59.000Z

496

Determining Reactor Neutrino Flux  

E-Print Network [OSTI]

Flux is an important source of uncertainties for a reactor neutrino experiment. It is determined from thermal power measurements, reactor core simulation, and knowledge of neutrino spectra of fuel isotopes. Past reactor neutrino experiments have determined the flux to (2-3)% precision. Precision measurements of mixing angle $\\theta_{13}$ by reactor neutrino experiments in the coming years will use near-far detector configurations. Most uncertainties from reactor will be canceled out. Understanding of the correlation of uncertainties is required for $\\theta_{13}$ experiments. Precise determination of reactor neutrino flux will also improve the sensitivity of the non-proliferation monitoring and future reactor experiments. We will discuss the flux calculation and recent progresses.

Jun Cao

2012-03-08T23:59:59.000Z

497

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

498

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

499

The thermonuclear rate for the 19F(a,p)22Ne reaction at stellar temperatures  

E-Print Network [OSTI]

The $^{19}$F($\\alpha$,p)$^{22}$Ne reaction is considered to be one of the main sources of fluorine depletion in AGB and Wolf-Rayet stars. The reaction rate still retains large uncertainties due to the lack of experimental studies available. In this work the yields for both exit channels to the ground state and first excited state of $^{22}$Ne have been measured and several previously unobserved resonances have been found in the energy range E$_{lab}$=792-1993 keV. The level parameters have been determined through a detailed R-matrix analysis of the reaction data and a new reaction rate is provided on the basis of the available experimental information.

Claudio Ugalde; Richard Azuma; Aaron Couture; Joachim Görres; Hye-Young Lee; Edward Stech; Elizabeth Strandberg; Wanpeng Tan; Michael Wiescher

2008-03-04T23:59:59.000Z

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Role of research reactors in training of NPP personnel with special focus on training reactor VR-1  

SciTech Connect (OSTI)

Research reactors play an important role in providing key personnel of nuclear power plants a hands-on experience from operation and experiments at nuclear facilities. Training of NPP (Nuclear Power Plant) staff is usually deeply theoretical with an extensive utilisation of simulators and computer visualisation. But a direct sensing of the reactor response to various actions can only improve the personnel awareness of important aspects of reactor operation. Training Reactor VR-1 and its utilization for training of NPP operators and other professionals from Czech Republic and Slovakia is described. Typical experimental exercises and good practices in organization of a training program are demonstrated. (authors)

Sklenka, L.; Rataj, J.; Frybort, J.; Huml, O. [Dept. of Nuclear Reactors, Faculty of Nuclear Sciences and Physical Engineering, Czech Technical Univ. in Prague, V Holesovickach 2, Prague 8, 180 00 (Czech Republic)

2012-07-01T23:59:59.000Z