FAST BREEDER REACTORS

Nuclear energy currently accounts for a declining share of global electricity, but it is possible that rising concerns about global climate change and China's ambitious nuclear program could reverse this trend. This review attempts to assess the global future of nuclear power, showing how the optimistic forecasts in the early days of nuclear power have been replaced by far more modest forecasts. The review first discusses the controversies surrounding nuclear power. It then briefly examines the prospects for three proposed reactors of the future: Small Modular Reactors; Generation IV breeder reactors; fusion reactors. It finally discusses the social and political context for nuclear power, both today and in the future.

This paper aims to compare three Monte Carlo (MC) burnup based codes, i.e. MCNP6, Monteburns and Serpent on a future prototype reactor, named ALLEGRO, based on Gas cooled Fast Reactor (GFR) technology. GFR reactors are one of the proposed Generation-IV fast reactors; ALLEGRO facility is scheduled to be built in Europe as a GFR demonstrator, so its deepened simulation can help in its future development. The present study follows other researches already performed and aims to exhibit the different approaches in burnup calculations applied to a gas cooled fast reactors, i.e. this paper would like to show and to compare some results concerning nuclear parameters as keff and flux spectra, as well as the mass inventories versus burnup for some nuclides evaluated with different Monte Carlo codes. From obtained results, it seems to exist some differences in evaluation of nuclear parameters, mainly in effective multiplication factor and in mass inventories. The remaining differences are mainly related to calculation time: indeed between the fastest, that is SERPENT, and the slowest, that are MCNP6 and MONTEBURNS, the differences are about one order of magnitude. As far as precision is concerned, it was considered the standard only for effective multiplication factor and it seems that all codes are in good agreement.

Focussing on Shevchenko/Aqtau, an urban laboratory of Soviet nuclear modernity on the Caspian Sea in Western Kazakhstan, this study provides a close reading of Soviet techno-politics in a long-term perspective. Encompassing a time span from the late 1950s to the present, the article traces how Shevchenko evolved from a secret uranium mining camp for the Soviet A-bomb project in the Western Kazakh desert into a testing ground for fast breeder and nuclear desalination technologies and a showcase of " atomic-powered Communism " (Josephson), but is now struggling with its transition into the post-Soviet era. Adopting a multi-dimensional perspective to show the interconnectedness of political, techno-scientific, ecological and social developments, the article highlights how the showcase city lent substance to the imaginary of the Scientific-Technological Revolution both domestically and abroad but also tracks the underlying decision-making processes in the Soviet nuclear establishment to reveal substantial disputes over questions of military versus civilian use and safety versus technological prowess. It analyses traits of the city's social microcosm to reveal the strictly segregated, but closely interconnected spheres of a privileged urban society and a sprawling, post-GULag forced labour camp, and adopts an enviro-technical perspective to study how the Promethean project of nature improvement eventually entailed grave environmental degradation. Finally, it sheds light on transsystemic cooperation across the block divide and highlights how Soviet visions of the future continue to shape visions of the future in Russia and Kazakhstan.

Based on a retrospective study of the French Fast-breeder Reactor (FBR) programme, this paper aims to show the dynamics of FBR demonstrator evaluation, with methodological inputs from the “Science and Technology Studies” branch of sociology. Such a reactor has to demonstrate the feasibility - including safety, technical and economic viability - of a promising technology regarded as a potentially inexhaustible energy source for the future. Until the mid-seventies, the need for an FBR fleet was regarded as urgent, entailing a focus on demonstration reactors to prove “technical” feasibility. But after the mid-seventies, the purpose of evaluating FBR projects was to prove the technical and economic viability of the programme, as well as its safety. The analysis of the Superphénix case is used to illustrate the difficulty of reconciling the three elements of assessment in a changing context, where the respective weights of the various criteria evolve in a dynamic fashion: it calls for an examination of the implicit specifications of demonstrators.

This article focuses on how political and technoscientific developments set each other’s pace in Soviet nuclear modernity, and points to a number of ways in which their diverging operational rationales were out of step, resulting in an uneasy combination of late‑Soviet technocratic visions with brute‑force modernisation carried over from Stalinist industrialization.

Abstract. In January 1959, from the platform of the XXI Party Congress, the communist leaders promised the Soviet people the developing of material and technical conditions for the transition to the Light Future at the end of the first seven years plan, and physicists promised unlimited
access to new energy sources. The promises of physicists remain  viable: today Russia is developing a thermonuclear reactor and is closing the nuclear fuel cycle. These ambitious technoscientific programs,
implemented in the USSR since the middle of the last century by  competing nuclear centers, have already demonstrated their ability to shape the national sociotechnical imaginaries, colonize the future,
accumulate symbolic capital and “long-term expectations”. Now they are integrated into the actual technological, political, economic and media landscapes. As the experience of the 2010s has shown the repertoire of Cold war propaganda, developed in the Soviet era, can be reused in contemporary Russia. Are the “engineering utopias” of the Late socialism subject to recycling? How do they work? Who and how is trying to adapt them to actual circumstances? How does the nuclear community, reacting to this re-installation, articulate its (non)readiness for a new round of long-term expectations revealing, thereby, the trace of utopia, planned economy, Big Soviet science and life, given to (not)implemented technoscientific program? The author answers these
questions by dissecting the discourse about the closure of the nuclear fuel cycle for breeder reactors. Through study of historical documents, memoirs, interviews with nuclear veterans, nuclear forums and media publications it will be shown that the closuring the nuclear cycle is not only a project and ideology, but also a specific way of nuclear community being in time.

We target at the periodic homogenization of a semi-linear reaction-diffusion-convection system describing filtration combustion, where fast drifts are triggered by the competition between heat and mass transfer processes in an asymptotic regime of dominant convec-tion. In addition, we consider the interplay between surface nonlinear chemical reactions and transport processes. To handle the oscillations occurring due to the heterogeneity of the medium, we rely on the concept of two-scale convergence with drift to obtain, for suitably scaled model parameters, the upscaled system of equations together with effective transport parameters. The main difficulty is to treat the case of a coupled multi-physics problem. We proceed by extending the results reported by G. Allaire et al. and other related papers in this context to the case of coupled system of evolution equations pertinent to filtration combustion.

Date : 1/01/2014
Revue : Science & Technology studies
Volume 27/2014, Issue 2

This paper considers a crucial moment in the innovation process: the shift from a research phase to an industrial phase. The empirical study examines the development in France of Fast Breeder Reactor technology (FBR), from the 1950s to the early closure of the Superphénix plant in 1997.

A turning point occurred in the late 1960s, when several European countries judged that the FBR technology was a promising electricity generation technology that would soon be mature for commercialisation, in a context of technological nationalism and future energy scarcity.

In this paper, we analyse how the framing of the resulting prototype as “industrial” entailed an impact on decisions during the three decades that the project lasted. Aiming at describing the project actors in action without judging their decision-making processes, we use the ‘framing’ concept preferably to other approaches such as ‘path dependency’.

This concept choice is the subject of the discussion. Keywords: nuclear technology, framing, prototypes

Thermal stripping is a phenomenon is defined as
the thermal fatigue occurred due to the flow of hot and cold
streams at different temperature with a temperature
the difference of about 100*c mixing in a fluid domain, result in an
arbitrary change of temperature field of the fluid domain with
respect to time. This random temperature fluctuation is
termed as Thermal Striping which leads to random

temperature fluctuations in the interface between the non-isothermal streams arising out of jet instability Thermal

stripping is analysis is carried out by both experimentally and
by using CFD analysis, for experimentation an experimental
set up is fabricated and the results from experimentation is
taken by data logger software, results from the experiment
recorded and these are the input values taken for CFD analysis,
importing recorded valves in CFD we get output results.This
both experimental valves and CFD analysis results are
compared and finally power spectral analysis is carried out
for three metals for utilization of this metals for future use in
fast breeder reactors as the inner core, The condition for satisfying
the utilization of metals as inner core without thermal striping phenomenon is that the metals should not exceed the
frequency(0.1-10)Hz
KeyWords: Thermal stripping phenomenon, Experimental
Analysis, CFD analysis, Power spectral density

We welcome the response from Baldev Raj to our article. 1 However, it does not satisfactorily address the issues raised therein. To begin with, it does not explain how 100 MJ is an upper bound on mechanical energy that could be released in a core disruptive accident (CDA). Raj states that safety studies have shown that mechanical energy release from loss of coolant flow together with failure of safety systems is less than 1 MJ. This contradicts DAE's published studies of the PFBR, 2 cited in our article, which show that energies on the order of 1000 MJ are possible. A key assumption in this calculation is the reactivity " insertion " rate (which depends on how much of the core collapses, in what configuration and how fast); the 100 MJ limit is based on assuming that only a part of the core participates in the accident. As we show in our article, the DAE's analysis that calculates the effect of the initiating events on the extent of core melting is limited by omissions (ignoring of cladding failure modes and the effects of burnup on fast reactivity feedbacks as well as fuel thermophysical properties) and therefore is unduly optimistic. Regarding the small CDA mechanical energy to thermal power ratio estimated for the Prototype Fast Breeder Reactor (PFBR) as compared to previous fast reactors, Raj points to other recent designs with even smaller figures. The problem is that the reactors he offers as counterexamples have not yet been cleared for construction by the appropriate safety regulators in those countries, let alone constructed. We see no reason to expect that French regulators , for example, would be satisfied with a reactor design that offers less containment strength than the Superphénix, after the series of accidents that the Superphénix experienced. The only reactor under construction in the list Raj offers is the Russian BN-800. However, this reactor has been designed to have a very small or negative sodium void coefficient and therefore is not the most relevant benchmark for the PFBR which has a large positive value. 3 The BN-800's containment design must also be seen in the background of the safety performance of Russia's breeder program. The largest reactor constructed so far, the BN-600, experienced 27 sodium leaks between 1980 and 1997, 14 of which resulted in sodium fires. 4 In most, if not all, cases, it appears that the reactor was not even shut down and continued operating as the fires were raging, indicating that inadequate priority is given to safety.

In the general context of increasing world energy demands and climate change, there is increasing pressure to develop sustainable energy technologies.  Nuclear energy can contribute to this, but although light water reactor (LWR) nuclear fission is broadly considered a low-carbon energy technology, there is a need to develop breakthrough technologies now in order to prepare for the longer-term future of nuclear power.  In particular, fast neutron reactors with closed fuel cycles, of which there are several design concepts, offer the potential to reduce the levels of high level waste and also contribute to the more efficient use of uranium resources, which may be put under pressure by an expansion of the LWR fleet.  Certain fast reactor concepts also have process heat applications, which may support economical hydrogen or synthetic hydrocarbon fuel production and there are also innovative systems such as the thorium fuelled molten salt and accelerator driven reactors (for transmutation of waste).  This broad class of next generation nuclear fission plant concepts are generally referred to as “Generation IV” systems or concepts. The foreseen operating conditions of the Generation IV concepts will place significant demands on their structural materials.  These demands are far more stringent than those for existing nuclear plant, and there will be a requirement for design lives in excess of 60 years.  Their material requirements have been well reviewed by numerous papers and candidate materials for critical component have been identified, drawing on experience of fast reactors prototypes operated in the latter part of the 20th century, some in the UK. The aim of this paper is to summarise recent developments within Europe in support of the design of Generation IV plant, and to highlight some issues concerning UK involvement in the structural integrity aspects of international fast neutron reactor research programmes.