Reactor Project Research Articles

Fusion energy far away

Hopeful followers of the 60-year saga of nuclear fusion as an energy source may have been disheartened by the timetable accompanying the official agreement on funding for the latest international fusion programme, signed in Paris on Nov 21, 2006. 1 United Kingdom Atomic Energy AuthorityUKAEA welcomes step forward for international fusion research. http://www.ukaea.org.uk/news/2006/21_11_06-2.htmlDate: Nov 21, 2006 Google Scholar At the level of physics, the thing is feasible; at the engineering and economic levels, there is less certainty. To be successful, the programme will need confidence in a nuclear future for power generation. Prevailing uncertainty and back-tracking on nuclear fission does not provide that confidence, nor does the political correctness of the fusion project's current title. ITER is indeed Latin for “the way”, but like it or not this is the International Thermonuclear Experimental Reactor. The much earlier ZETA stood for Zero Energy Thermonuclear Assembly until the T became Toroidal instead. Hiding “nuclear” and “experimental” in ITER fools no-one, and certainly not environmental action groups, which strongly object to the construction at Cadarache in southern France, which is scheduled for completion by 2015. 2 Greenpeace InternationalNuclear fusion reactor project in France: an expensive and senseless nuclear stupidity. http://www.greenpeace.org/international/press/releases/ITERprojectFranceDate: June 28, 2005 Google Scholar

Scientists Reap ITER's First Dividends

FUSIONIn an agreement due to receive provisional approval this week, some $870 million will be spent on fusion-related facilities in Japan that will complement the International Thermonuclear Experimental Reactor (ITER) project. Japan and the European Union will make equal contributions to this new program. ([Read more][1].) [1]: http://www.sciencemag.org/cgi/content/full/314/5803/1227a

Conceptual design of a High Temperature Superconductor current feeder system for ITER

The International Thermonuclear Experimental Reactor (ITER) project envisages a techno-economically feasible solution of its current feeder system in order to reduce the overall cryogenic requirements and operational costs. Since the ITER magnet system has a long stand-by time with respect to its operation duty cycle, it is essential to optimize the operational costs of the current feeder system taking into consideration both, the full current and stand-by modes. The present HTS technology has reached the maturity that HTS conductors are applicable for the current feeder system of ITER. The replacement of the actually planned conventional current leads by HTS current leads would provide considerable savings in the refrigeration investment and operational costs. Another option is the substitution of the water cooled high current aluminum feeders by HTS feeders, so called HTS bus bars. In this paper, the different design options of Bi-2223/Ag HTS based bus bars as prototype unit modules for ITER are discussed. The performance of different cooling schemes for HTS bus bars is studied and the design related critical issues e.g. metallic transition (65 K −300 K) and bending of bus bar, AC loss, thermal loss and reliability of the cooling system are investigated.

On the Proliferation Potential of Uranium Fuel for Research Reactors at Various Enrichment Levels

This article reviews the rationale of selecting an enrichment of just less than 20% (low-enriched uranium) as the preferred enrichment level for research reactor fuel in order to minimize overall proliferation risks. The net strategic value of the nuclear material associated with reactor operation is evaluated for a variety of enrichment levels, ranging from slightly enriched to weapon-grade fuel. To quantify the proliferation potential, both the demand of fresh uranium fuel as well as the plutonium buildup in the irradiated fuel are estimated via cell burnup calculations. The analysis confirms the usefulness of the current enrichment limit and challenges a recent trend to reconsider fuel enrichment levels between 20% and 50% for new research reactor projects.

A support vector machine integrated system for the classification of operation anomalies in nuclear components and systems

A support vector machine (SVM) approach to the classification of transients in nuclear power plants is presented. SVM is a machine-learning algorithm that has been successfully used in pattern recognition for cluster analysis. In the present work, single- and multiclass SVM are combined into a hierarchical structure for distinguishing among transients in nuclear systems on the basis of measured data. An example of application of the approach is presented with respect to the classification of anomalies and malfunctions occurring in the feedwater system of a boiling water reactor. The data used in the example are provided by the HAMBO simulator of the Halden Reactor Project.

Fusion Leaders Make a Diplomatic Choice

ITERCAMBRIDGE, U.K.-- A Japanese diplomat has been chosen to head the International Thermonuclear Experimental Reactor (ITER) project, the world's most expensive scientific collaboration.

Investigation of potential operation issues of human-system interface in lungmen nuclear power project

The Lungmen Nuclear Power Project (LMNPP) with 1350 MWe twin units is the first advanced boiling water reactor (ABWR) project owned by the Taipower Company in Taiwan. Video display units are the main human-system interface for operators to manipulate, i.e., so-called "soft" control, and to know the status of the equipment and plant information. Several concerns arise when compared to hard controls. These concerns led us to conduct an investigation of the operator's performance and the potential issues regarding the operator's teamwork. The results of the investigation show that the most important task is to establish an intensive training program that addresses the knowledge and skill requirements of the operators to meet the task characteristics and the responses of the plant processes.

Effects of heat input on the microstructure and toughness of the 8 MnMoNi 5 5 shape-welded nuclear steel

A weld metal well proven in the German nuclear industry served as the basis for the certification of a shape-welded steel to be used as base material for manufacture of nuclear primary components. The outstanding properties of this steel are attributed to the extremely fine-grained and stable primary microstructure. Subsequent reheating cycles caused by neighbouring weld beads do neither lead to coarsened brittle structures in the heat-affected zone nor to increase in hardness and decrease in toughness, as is the case with wrought steel materials. One of the largest new reactor vessel design amongst today’s advanced reactor projects is considered to be particularly suitable for the use of shape-welded parts in place of forgings. In addition the need for design and development of new shape-welded steel grades for other new generation reactor projects is emphasized, in which the experience gained with this research could make a contribution.

Past and present research in europe on the production of nuclear hydrogen with HTGR

The High-Temperature Gas-Cooled Reactor represents a suitable concept of a future nuclear power plant with efficient and economic and safe generation of energy. Its potential to produce process heat at high temperatures can be utilized in many industrial processes for the generation of hydrogen or other synthetic chemical fuels, which may find broadening application on the future world energy markets. The paper includes a description of the German long-term projects “Prototype Nuclear Process Heat Reactor Project” (PNP), in which the technical feasibility of an HTGR in combination with coal gasification processes has been proven, and “Nuclear Long Distance Energy Transportation” (NFE), a verification and demonstration of the closed-cycle, energy transmission system EVA/ADAM. But also the new research activities in Europe encouraged and supported by the Commission of the European Union within their Framework Programmes will be outlined. The Michelangelo Network (MICANET) has been created in 1997 by 19 European partners to elaborate a general European R&D strategy for the further development of the nuclear industry with a strong focus on innovative nuclear reactor designs. The Hydrogen Network (HYNET) established in 1999 is working on the development of strategies for the introduction of a European hydrogen fuel infrastructure. Both networks are paving the way for subsequent proposals for EU supported research projects such as V/HTR, HYSAFE, INNOHYP.

A perspective on fast reactor fuel cycle in India

The growing energy needs of India can be fulfilled only by judicious mix of all the fuel resources. It is possible to achieve energy security and sustainability through the introduction of fast reactors in an expeditious manner and closing the fuel cycle. This approach is inevitable in view of the limited uranium resources in India. The Fast Breeder Test Reactor (FBTR) built by India uses mixed carbide as fuel and the 500 MW(e) Fast Breeder Reactor Project (PFBR), to be operational in 2010, will use mixed oxide as fuel. It has also been decided that fast reactors beyond 2020, with enhanced safety features and having better economy, will use metallic fuel. Having successfully operated FBTR with carbide fuels, we need to develop the fuel cycles for both the mixed oxide fuel in the near future and the metallic fuel expeditiously. The progress achieved so far and the plans for implementation are discussed in this paper.

Intelligent systems integration: Guiding Principles, examples and lessons learned

The adoption of support systems based on computational intelligence (CI) techniques in nuclear power plants presents a number of challenges that need to be addressed in order to maximise the added value of this type of systems. This paper tackles issues related to the integration of CI systems and identifies three different levels of integration that should be taken into consideration. These are the data level, the operational level, and the functional level. The data level includes all aspects of data communication between the CI system, the plant instrumentation, and the other computerized support systems present at the plant. The operational level includes all those aspects of integration that influence the way in which the operator interacts with the CI system, with a clear emphasis on Human System Interface (HSI) integration. The functional level includes those aspects of integration that deal with the functionality of the CI system and how this can support or be combined with the functionality offered by other support systems with the aim of exploiting synergistic effects and achieving new functions. Additionally, the paper identifies a set of guiding principles of integration that can be applied at all three levels of integration. Examples taken from experiences gathered at the OECD Halden Reactor Project are also included.

Research and development of lithium ceramics and models of tritium breeding zones for blankets in Russian reactor projects

Main results of in-pile reactor testing of the first model of the tritium breeding zones (TBZ) for fusion reactor blankets containing both lithium orthosilicate and beryllium spheroid particles are presented. Experimental results of tritium inflow – in the form of HT and HTO – into neon purge-gas with or without 1% hydrogen are discussed.

The quality of human-automation cooperation in human-system interface for nuclear power plants

The use of automation within high-risk industrial production systems has increased markedly during the last 50 years. Automatic systems have gained in autonomy and authority, whereby the activity of the systems has become less dependent on operator interventions. This has brought forward the suggestion that human-automation transactions should be conceptualized within the framework of cooperation, and consequently that automatic systems should be designed to be cooperative. The question is then how design can promote human-automation cooperation, and how the quality of cooperation can be assessed. The OECD Halden Reactor Project performed two closely related experiments, which allowed assessments of whether the quality of human-automation cooperation would be promoted by a human–machine interface designed to increase the observability of the automatic system's activity using graphical and verbal feedback, as compared to a conventional human–machine interface. The experiments were performed in a full-scale nuclear power plant simulator, using licensed operators as subjects, and applied a 2×2 within-subject design. The quality of human-automation cooperation was assessed from subjective operator judgements. The experiments demonstrated a clear improvement in human-automation cooperation quality when the observability of the automatic system's activity was increased. The relationship between human-automation cooperation quality and the effectiveness of the joint human–machine system's performance was furthermore explored, but no clear results were found. As the trend in automation design seems to imply an increase in system autonomy and authority, the issue of human-automation cooperation can be expected to further gain in importance in the future settings.

Japanese policy on the science and technology research

Science and technology policy in Japan with special emphasis on energy research was presented beginning with an introduction of the Council for Science and Technology Policy. The fact that in the year 2000 in Japan, petroleum and coal, which are sources of greenhouse gas, contributed about two-thirds of the total energy production is pointed out as the key issue of energy and the environment. As one of the action to solve the problem, Japan emphasizes research of innovative energy technology. As a policy, Japan will not only participate but will invite ITER as host, the international thermonuclear experimental reactor project. Japan, as one of the leading countries in fusion research, seeks a broad viewpoint for advanced science and technology because fusion is related to the frontiers of physics. Cost effectiveness and public understanding are required in all the scientific programs.

Modified APEX reactor as a fusion breeder

An advanced fusion reactor project, called APEX, with improved effectiveness has been developed using a protective flowing liquid wall for tritium breeding and energy transfer. In the modified APEX concept, the flowing molten salt wall is composed of Flibe as the main constituent with increased mole fractions of heavy metal salt (ThF 4 or UF 4) for both fissile and fusile breeding purposes and to increase the energy multiplication. Neutron transport calculations are conducted with the help of the SCALE4.3 SYSTEM by solving the Boltzmann transport equation with the code XSDRNPM. By preserving a self sufficient tritium breeding ratio (TBR > 1.05) for a mole fraction up to 6% of ThF 4 or 12% of UF 4, the modified APEX reactor can produce up to ∼2800 kg of 233U/year or ∼4950 kg of 239Pu/year, assuming the same baseline fusion power production of 4000 MW th, as in the original APEX concept. With 6% ThF 4 or 12% UF 4 in the coolant, the total energy output will increase to 5560 MW th or 8440 MW th, respectively. For a plant operation period of 30 full power years, the atomic displacement and helium production rates remain well below the presumable limits. The additional benefits of fissionable metal salt in the flowing liquid in a fusion reactor can be summarized as breeding of high quality fissile fuel for external reactors and increase of total plant power output.

Just ITER It

Encouraged by a spate of positive reviews, the U.S. government will rejoin the International Thermonuclear Experimental Reactor (ITER) project, a fusion power experiment. The U.S. quit an earlier version in 1998 due to cost concerns but is more positive about the current $5 billion design. Still, the U.S. might balk at coughing up the $100 million or more per year expected of full partners.

Plasma multivariable robust control system design and simulation for a thermonuclear tokamak-reactor

The paper reports results on the design and analysis of the multivariable feedback Hinfin; robust system for plasma current, position and shape control in the fusion energy advanced tokamak (FEAT) developed in the International Thermonuclear Experimental Reactor (ITER) project. The system contains the fast loop with the SISO plasma vertical speed robust controller and the slow loop with the MIMO plasma current and shape robust controller. The goal is to study the resources of the system robustness to achieve a higher degree of the FEAT operation reliability. Two Hinfin; block diagonal controllers {K SISO, K MIMO} were designed by a mixed sensitivity approach in the framework of the disturbance rejection configuration. These controllers were compared with block diagonal decoupling, PI and LQG controllers at the set of FEAT key scenario points according to the multiple-criterion: nominal performance at minor disruptions, robust stability and robust performance. The Hinfin; controllers showed larger multivariable stability margin and better nominal performance.

Integrating cross-correlation techniques and neural networks for feedwater flow measurement

This paper reports an early progress of a feasibility study of a computational intelligence approach to the enhancement of the accuracy of flow measurements in the framework of an ongoing cooperation between Tecnatom s.a. in Madrid and the OECD Halden Reactor Project (HRP) in Halden. The aim of this research project is to contribute to the development and validation of a flow sensor in a nuclear power plant (NPP). The basic idea is to combine the use of applied computational intelligence approaches (noise analysis, neural networks, fuzzy systems, wavelets etc.) with existing traditional flow measurements, and in particular with cross-correlation flowmeter concepts.

High performance light water reactor

The objective of the high performance light water reactor (HPLWR) project is to assess the merit and economic feasibility of a high efficiency LWR operating at thermodynamically supercritical regime. An efficiency of approximately 44% is expected. To accomplish this objective, a highly qualified team of European research institutes and industrial partners together with the University of Tokyo is assessing the major issues pertaining to a new reactor concept, under the co-sponsorship of the European Commission. The assessment has emphasized the recent advancement achieved in this area by Japan. Additionally, it accounts for advanced European reactor design requirements, recent improvements, practical design aspects, availability of plant components and the availability of high temperature materials. The final objective of this project is to reach a conclusion on the potential of the HPLWR to help sustain the nuclear option, by supplying competitively priced electricity, as well as to continue the nuclear competence in LWR technology. The following is a brief summary of the main project achievements: • A state-of-the-art review of supercritical water-cooled reactors has been performed for the HPLWR project. • Extensive studies have been performed in the last 10 years by the University of Tokyo. Therefore, a ‘reference design’, developed by the University of Tokyo, was selected in order to assess the available technological tools (i.e. computer codes, analyses, advanced materials, water chemistry, etc.). Design data and results of the analysis were supplied by the University of Tokyo. A benchmark problem, based on the ‘reference design’ was defined for neutronics calculations and several partners of the HPLWR project carried out independent analyses. The results of these analyses, which in addition help to ‘calibrate’ the codes, have guided the assessment of the core and the design of an improved HPLWR fuel assembly. • Preliminary selection was made for the HPLWR scale, boundary conditions, core and fuel assembly design, reactor pressure vessel, containment, turbine and balance of plant. • A review of potentially applicable materials for the HPLWR was completed and a preliminary selection of potential in-vessel and ex-vessel candidate materials was made. • A thorough review of heat transfer at supercritical pressures was completed together with a thermal-hydraulics analysis of potential HPLWR sub-channels. This analytical tool supports the core and fuel assembly design. • The RELAP5 and the CATHARE 2 codes are being upgraded to supercritical pressures. Thus they can be used to support the HPLWR core design and to perform plant safety analyses. • Assessment of the HPLWR design constraints, based on current LWR technology was documented. This document stresses the various criteria that must be satisfied in the design (e.g. material, temperature, power, safety criteria, etc.) based on experience gained in the design of PWR. • Preliminary economic assessment concluded that the HPLWR has the potential to be economically competitive. However, an accurate assessment can only be done after the HPLWR design has been fixed. A more accurate economic assessment may be performed after the conclusion of this project.

Current status of TRR-II neutron-spectrometer designs

The objective of the Taiwan Research Reactor project is to modify the Taiwan Research Reactor (TRR) into a multi-purpose medium-flux research reactor (TRR-II). The project started in 1998, and the estimated maximum unperturbed thermal neutron flux (E<0.625 eV) of the new reactor is approximately 2.7×1014 n/cm2 s. The major application areas of TRR-II are: neutron scattering in material and biological researches, material tests, neutron-activation analyses, isotope production and industrial applications.