moderator in fast breeder reactor

production reactor and an enrichment plant as secret. (c) either fast or slow neutrons It is found that, the ISMRAN set-up can observe the active-sterile neutrino mixing sensitivity for $$\sin ^{2}2\theta _{14} \ge 0.064$$ and $$\varDelta m^{2}_{41} = 1.0$$ $$\hbox {eV}^2$$ at $$90\%$$ confidence level for an exposure of 1 ton-year by using neutrinos produced from the DHRUVA reactor with thermal power of $$100 \hbox {MW}_{{th}}$$. This is roughly. Which of the following nuclear reactor does not need a heat exchanger for generation of steam This experimental feedback can highlight several recommendations and a general approach for the decommissioning of future LMFRs still in operation. (c) instantaneous release of gamma rays (a) 1 MeV (a) the original elements change into completely different elements (b) accelerating fast neutrons The studies show that while maintaining the performance of commercial reactors their breeding gain can be further, Howard Gest was a member of the "Charles Coryell Chemistry Group" of the Manhattan (Atomic Bomb) Project at the University of Chicago and in the "secret city" of oak Ridge (TN). In the breeder reactors the generation of new fissionable atom is (c) produce more fuel than they consume Ans: a, 43. Copyright 2020 , Engineering Interview Questions.com, 300+ TOP Nuclear Power Plants Multiple Choice Questions and Answers. This is not possible with advanced LWRs, which can be considered only as a possible backup solution for plutonium recycling into PWRs. (b) boiling water The analysis is performed considering both the reactor and detector related parameters. (c) curie (a) light weight atoms (b) atomic number (d) to prevent the water coolant from boiling in the core Corresponding numerical interpretations have been conducted with 3D Navier-Stokes model in CAST3M code. (b) more (e) none of the above (e) equal to infinity. (c) 10 tonnes of high grade coal (e) none of the above. Ans: b, 33. In this way the breeder reactor can produce both energy and more fuel. (d) electrons in the atom Plutonium-239 is produced A fast breeder reactor consists of a core, an inner blanket consisting of a single ring of blanket elements surrounding the core, an outer blanket surrounding the inner blanket and a partition containing a moderating material and, preferably, a material which absorbs thermal neutrons separating the inner blanket from the outer blanket. (c) any form of uranium While the initial purpose was to obtain plutonium for the nuclear weapons program, very early on, the fast breeder reactor became a second strategic goal. (e) negative, i.e. (a) as basic raw material Spain joined the consortium in 1959. (c) slightly less (a) natural uranium In a fission process, maximum %age of energy is released as Ans: c, 54. (e) 2 x 105. Ans: b, 60. (c) U238 (d) moderator may or may not be used (c) critical neutrons (e) 20 MeV. Because nuclear energy is an established technology (unlike many of the proposed technical fixes for our global environmental and resource problems), there is a factual basis for the discussion of these factors. (b) protons Uranium-233 is produced (e) moderate the radioactive pollution. (c) a, P, and y rays Superphénix only operated about half of the time that it was officially connected to the grid and was shut down in 1998 with a lifetime load factor of less than 7%. (b) high initial cost Any reactor that contains fertile species 232 Th, 238 U, or 240 Pu produces some amount of new fissile fuel. 36. Ans: b, 45. (d) electron The first unclear power plant in India is located at (a) Kota (b) Kalapakkam (c) Tarapur (d) Baraeilly (e) Kerala. Ans: a, 38. proximately 45% is one of the lowest in the world. (e) higher/lower depending on the size of reactor. (b) 10 MeV (a) operate at extremely high power densities. in March and November 1984, and in September 1988. was considered not to constitute an immediate safety issue, The ﬁrst cladding failure was detected in May 1979. This note details the negative consequences for any nuclear role for France at medium and long time. (e) none of the above. Controversy has embroiled all aspects of nuclear power: the safety of reactors, the extent of uranium resources, the effects on health of low levels of ionising radiation, the likelihood of nuclear weapons proliferation, and the effectiveness of various nuclear waste disposal methods. The reactor fuel is surrounded by a "blanket" of non-fissionable U-238. (e) Pu He did not discuss whether any steps were being taken to dismantle the fissile material production infrastructure in China or limit China's ability to restart production. The fissile material is plutonium. Ans: a, 61. The so-called $$3+1$$ scenario is considered for active-sterile neutrino mixing, which leads to projected exclusion curves in the sterile neutrino mass and mixing angle plane. Ans: b, 64. (b) Slow or thermal neutrons have energy of the order or 0.025 eV (a) reduce temperature (c) same (a) %age of U235 has been artificially in-creased In this reactor no moderator is used. The efficiency of a nuclear power plant in comparsion to a conventional thermal power plant is Ans: a, 78. (b) the basic fuel for nuclear paints (c) 2000 (c) graphite and concrete Unfortunately, these objectives had to be limited to a conversion ratio of 0.9 for safety reasons, and it is not certain whether operation will be rewarding economically. (a) slowing down fast neutrons so that Uz fission continues by slow motion neutrons (e) none of the above. The fissionable fuel core is surrounded by a blanket of fertile material (U-238 or Th- 232). (d) boiling water (a) plutonium In a typical pressurized-water reactor, the water itself acts as this moderator. Thorium-uranium fuel cycle. Ans: c, 37. This chapter marks where the long, successful story of nuclear decommissioning has arrived today. (a) more (d) lower temperature and pressure condi-tions (c) has no moderator (c) pressurised water (b) slightly more (c) basic raw material for nuclear plants The coolant used in boiling water reactor is Ans: a, 6. Figure 1 â Types of Nuclear Reactors Plus radium (element 88). The nation’s nuclear power industry is in trouble. (d) 7.8 MeV (e) chain reaction. 2 Further complicating any analysis, China still treats details about a key plutonium, The possibilities of breeding in liquid-metal fast breeder reactors (LMFBRs) and light water reactors (LWRs) are compared in two ways. Home » Mechanical Engineering Multiple Choice Questions » 300+ TOP Nuclear Power Plants Multiple Choice Questions and Answers, 1. Ans: b, 46. (a) neutron (e) unpredictable. (d) 1-75% (b) U-238 Ans: d, 28. (e) use water as coolant. Additionally, neutronic simulations were conducted in order to verify that, in nominal operational conditions, its coupling with thermal-hydraulics and thermomechanics is of minor importance. The reformulation of these laws using the developed coupled simulation methodology constitutes a perspective of this work. (c) U235andPu235 In this conservative approach, the thermal-hydraulic simulations are conducted without considering the geometrical deformation, and the resulting temperature distributions are used as input for the thermomechanical simulations. Which is not identical for an atom and an isotope In thermal reactors, which comprise the bulk of the worldâs nuclear power fleet, the fission neutrons are slowed down to low (thermal) energies by collisions with light atoms within the reactorâhydrogen in the water in water-cooled reactors, deuterium in heavy water in hâ¦ Ans: c, 35. (d) U238andPu239 A breeder reactor is essentially a particular configuration of afast reactor. (c) uniform throughout Ph enix ́ heat exchanger with insulation removed after sodium fire. equivalent of one reactor core (see Figure 2). Unlike the other declared nuclear weapon states, China has yet to officially state that its production of fissile materials for weapons has ended. In triggering fission, which type of neutrons are more effective Figure 1. Ph enix ́ operating costs, 1972–2003 (FRF 2000 million), Source: Sauvage 2004. (c) by neutron irradiation of throium (d) there is no such criterion (c) U-235 (e) U-239. Moderators are used to slow down the neutrons without absorbing them. (a) gas cooled (d) radio activity The most practical fuel for a thermo-nuclear reactor, both from econocical and nuclear consideration is (d) meson ´ echec des surgénérateurs, autopsie d'un grand programme. Uranium-238 is a fertile isotope and will react with a fast neutron to produce more plutonium-239. Both cycles have advantages and disadvantages, especially depending on the kind of reactor used. (d) lead, H2 Germany, France, Belgium, Italy, Sweden, Austria, Denmark, Norway, Netherlands, Switzerland, Portugal, Turkey. Ans: c, 42. (a) fast moving 2006, see http://www-frdb.iaea.org/index.html. By reducing by 20 to 30% the French production of nuclear energy, one would suppress all the reactors functioning presently with the MOX fuel. (a) protons in the nucleus This memoir describes activities in Oak Ridge and documents the history of the ill-fated secret Szilard Petition addressed to President Truman. (d) decreased leakage of neutrons (c) 199 MeV The risk of radioactive hazard is greatest in the turbine with following reactor (b) kinetic energy of fission products (b) protons and electrons in an atom (b) is inert (a) does not absorb neutrons Ans: b, 53. 3 He added: "Military production has been reduced to the minimum -on State orders, and development of nuclear electric power is our main task." (c) equal to 1.0 (d) initiated Pressurised water reactor isdesigned Which of the following is more appropriate for a moderator. (b) beta particles (a) increased production of neutrons The coupling has been implemented via the exchange of the cladding deformation, calculated by DOMAJEUR2, and its associated temperature field, obtained with a CFD model implemented in STAR-CCM+ that explicitly considers the geometrical deformation of the fuel pins. (d) unity (e) none of the above. magazine, 19 September 1977, quoted in [F. The fuel pin bundles of Sodium-cooled Fast Reactors (SFR) undergo significant geometrical changes during their irradiation, which affect the coolant flow and temperature distributions in the fuel assemblies, the knowledge of which is essential for safety assessments. (c) equal to zero (a) atomic power Fast breeder reactor uses PUG 1989, p. 176. The construction of the fast breeder requires a higher enrichment of U-235 than a light-water reactor, typically 15 to 30%. Breeder reactor has a conversion ratio of (a) Kota (e) regenerates neutrons. (c) U238andPu239 (d) MeV (a) Ulii One gram of uranium will produce energy equivalent to approximately Breeder reactor, nuclear reactor that produces more fissionable material than it consumes to generate energy. (c) reciprocation (d) using moderator The conclusions reached differentiate between the decentralized and liberal U.S. plutonium economy from the British and the French state-controlled economies largely serving military interests. Ans: d, 19. (e) electrons. R. Galley, C. Bataille, Rapport fait au nom de la Commission d'Enqu****ete sur (a) same A reticulate model with homogenised linear hypothesis has been developed to interpret PISE-2C experiments. (d) boiling water reactor Ans: e, 9. (d) to provide subcooled water at high pressure The fast reactor has no moderator and relies on fast neutrons alone to cause fission, which for uranium is less efficient than using slow neutrons. (c) critical atoms Breeder reactors producing uranium 233 out of thorium can breed with thermal neutrons and do use moderators. (b) more than unity mean a credit of less than FRF1 billion for the generation of the 3.65 TWh. (e) Most serious drawback in using water as coolant in nuclear plants is its high vapour pressure. Moreover, as the mechanisms responsible for the deformation of the fuel bundles, namely the swelling and creep, strongly depend on the fuel cladding temperature, a coupling between the thermal-hydraulic and thermomechanical evolutions of the fuel assemblies exists. The following present serious difficulty in designing reactor shield (d) more than one new neutrons Most of these countries had nuclear weapons programs or ambitions at some point. (c) 99.282% U234, 0.712% U238, 0.006% U235 Artificial radioactive isotopes find application in (b) plutonium Reflector in nuclear plants is used to (a) 20 (e) no moderator is used. (e) none of the above. (d) zero throughout The article will investigate the possibility of a nuclear revival in this country by first analyzing the troubled history of the light water reactor, a technology that dates back to the 1950s, and one the federal government choose to pursue to ensure America’s technological leadership, and one the nuclear manufactures heavily promoted to ensure profitability. Ans: c, 26. (b) lower It is penetrated from end to end by hundreds of calandria tubes which accommodate the pressure tubes containing the fuel and coolant. Ans: d, 83. to the First " Castaing Report, " commissioned by the Conseil Supérieur de la S ˆ Ans: b, 32. (e) much more. as the breeder and there is no moderator unlike in a thermal reactor (substance that slows down the neutrons, e.g. (c) 1 – 2 neutrons Recently, the old idea of breeding in advanced pressurized water reactors (PWRs) has been taken up again with the objective of attaining a gain of 0.05. (a) greater than 1.0 In the scheme of French ASTRID (Advanced Sodium Technological Reactor for Industrial Demonstration) project, fluid-structure interaction phenomena involved in the dynamic behaviour of core flowering, which could happen during seismic events, are of high interest. (b) fast breeder reactor Superphénix et lafilì ere des réacteursréacteursréacteursà neutrons rapides, enregistréenregistréenregistréà l'Assemblée (e) in high capacity furnaces. Ans: a, 55. (d) 168 MeV (d) medium energy neutrons (c) thermal neutrons Ans: b, 89. A boiling water reactor uses following as fuel (e) in high capacity furnaces. (a) acts as good moderator (b) enriched uranium will not restart, not even for a limited period of time. Electron-volt is the unit of (e) infinite. Which of the following is the primary fuel (d) graphite (d) may be less or mote depending on size Moderator in nuclear plants is used to The Superphénix predecessor, Phénix at Marcoule, which began operating in 1973 and will be shut down later in 2009, has experienced numerous sodium leaks and fires and a series of potentially serious reactivity incidents. The breeding gain in case of thermal breeder reactor as compared to fast breeder reactor is Ans: a, 24. The energy required to be applied to a radioactive nucleus for the emission of a neutron is An analysis of the accident concluded later: heterogeneous physical-chemical environment, complex and multiphasic made of, action and/or catalytic exothermal reactions. (a) higher cost of nuclear fuel Ans: a, 40. (c) neutrons (d) extra energy is pumped from outside (c) graphite or cadmium Mechanical Engineering Multiple Choice Questions. The number of operating reactors continues to decline, while only one new plant is scheduled to open and it is well behind schedule and 50% over budget. Dominique Finon, L'´ echec des surgénérateurs, autopsie d'un grand programme, Pick up the wrong statement (b) at least one new neutron (b) at a higher rate than the constuption Ans: d, 76. reactors, TECDOC 1405, IAEA, August 2004. (c) the molecules rearrange themselves to form other molecules (c) by neutron irradiation of thorium 1.7K views (a) same atomic number and different masses Despite such statements, the status and operational history of Chinese production reactors and enrichment plants remain shrouded in mystery. A nuclear fission is initiated when the critical energy as compared to neutron binding energy of the atoms is (b) 99.282% U235, 0.712% U238, 0.06%’ U234 (b) energy (e) neutron. Issues of New Technological Trends in Nuclear Power Plant (NPPs) for Standardized Breakdown Structure, Development of a thermal-hydraulics/thermomechanics coupling model for the evaluation of the behavior of SFR fuel assemblies under irradiation, Analysis of fluid-structure interaction in a sodium fast reactor core : experimental, theoretical and numerical evaluation of damping and frequencies, Reckless Proliferation and Guardianship Proliferation: The Fast Breeder Nuclear Reactor and the Plutonium Economy, Sensitivity to sterile neutrino mixing using reactor antineutrinos. (b) 1-25% electronics, robotics), new social expectations, political priorities, and cost constraints making a virtue of necessity. (a) boiling water Fast breeders do not require moderationsince the neutrons need to be moving fast, whereas thermal breeders make us of moderation to achieve slower-moving neutrons. (d) cause collision with the fast moving neutrons to reduce their speed (d) uses ferrite material as moderator (e) it produces tremendous power. (d) position in periodic table (a) 1-99% Two series of free-vibration experiments have been performed on PISE-1A with different water heights and different mass fractions of water-glycerol mixtures to examine the dynamic behaviours with respect to different added mass, different densities and viscosities. U235 will undergo fission by And what were the interconnections between the production of plutonium for nuclear reactors and plutonium for atomic bombs? The unit of radio-activity is Finally, a contribution to the validation of the developed coupled simulation methodology was realized by performing a numerical benchmark against a preexisting coupled simulation tool, and by simulating the irradiation of an experimental fuel assembly. Which of the following particles is the lightest (b) the electrons of the element change (c) pins (d) nulceus (e) protons and electrons in a nucleus. (d) zero (e) infinity. (b) slow moving (c) proton (c) less than unity (b) U (d) control rods should be used (d) gradual readioactive decay of fission products Also the date of the final shutdown of the PFR in Dounreay. (d) 2 — neutrons (d) sodium graphite (c) accelerates neutrons Which of the following are ferrite materials (a) high energy (fast) neutrons alone (d) are unmoderated (b) moderator should be used (e) unpredictable. (a) as basic raw material Which of the following is the heaviest (e) none of the above. (a) it is generating power to rated capacity Which of the following is secondary fuel Ans: a, 62. GENERAL REVIEW OF THE DECOMMISSIONING OF LIQUID METAL FAST REACTORS (LMFRs) IN FRANCE, Le plutonium et la cohérence du parc électronucléaire français, Chinese Military Plutonium and Highly Enriched Uranium Inventories, Plutonium Breeding in Liquid-Metal Fast Breeder Reactors and Light Water Reactors, The July 1945 Szilard Petition on the Atomic Bomb Memoir by a Signer in Oak Ridge. (d) liquid metal cooled Ans: e, 34. All of this resulted in a rush to nuclear power in the 1960s, but abruptly ended a little more than a decade later, due largely to the exorbitant costs of constructing a nuclear plant. (c) 4.3 MeV Gas cooled reactor uses following materials as moderator, and coolant (d) fast neutrons and gamma rays A fast breeder reactor uses following as fuel (e) medical field. Reactors for propulsion applications use (e) moderator is dispensed with. Ans: d, 5. That means the neutron moderator (slowing down) in such reactors is undesirable. Fast breeder reactors which use uranium-238 as fuel and thermal breeder reactors which use thorium-232 as fuel. (e) none of the above. (a) return the neutrons back into the core (d) conserve energy Amongst the following, the fissionable materials are (a) demineralised water (d) chain reaction that causes automatic splitting of the fuel nuclei has been established It used a Na-K eutectic alloy that was liquid at room temperature as a coolant. Research of the group was focused on characterization of the numerous radioactive isotopes created during uranium fission, development of a process for chemical isolation of plutonium, and preparation of gigantic amounts. (e) ferrite reactor. No moderator is used in the breeder reactor since fast neutrons are more efficient in transmuting U-238 to Pu-239. (a) U233andPu239 Most Asked Technical Basic CIVIL | Mechanical | CSE | EEE | ECE | IT | Chemical | Medical MBBS Jobs Online Quiz Tests for Freshers Experienced. (c) coolant should be employed Edge effects are not found to have an important impact on the dynamic behaviours of the system. (e) none of the above. In fast breeder reactors In 1994, for example, Jiang Xinxiong, then-general manager of the China National Nuclear Corporation, said that "most of the nuclear factories are closed or have stopped operation." (a) 5 MeV (b) fission breeder reactor type, because there you have plutonium of extraordinary mili-. (a) natural uranium (c) boiling water campaign. (c) controlled production of neutrons A nuclear power reactor controls the fission chain reaction by moderating the neutrons and with the use of control rods which may be inserted in the reactor core to absorb neutrons and slow down the reaction. (c) in bulk As Argonne explains it, when an atom in a nuclear reactor âfissionsââor splits into several smaller fragmentsâneutrons are released at high energy (fast speeds). to operate at a nominal capacity of 400 tons per year, The mean duration of reactor runs was 80 da, tions (see below). (b) low energy (slow) neutrons alone Breeder reactors employ liquid metal coolant because it (e) decrease of speed of neutrons. Which of the following can be used as a coolant in nuclear plant (e) kWhr. The efficiency of a nuclear power plant in comparison to conventional and nuclear consideration is The energy produced by a thermal reactor of same size as a breeder reactor is (b) shield the radioactivity completely Ans: d, 23. (d) deutrium (b) carbon dioxide The fast breeder reactor uses the following moderator (a) demineralised water (b) carbon dioxide (c) heavy water (d) graphite (e) no moderator is used. There are several concepts for breeder reactors; the two main ones are: The first unclear power plant in India is located at Neutrons without absorbing them, can you please send me all thease Mechanical pdfs ksachink7... Norway, Netherlands, Switzerland, Portugal, Turkey plutonium as nuclear.. Is surrounded by a blanket of fertile material is uranium-238, the water itself acts as this.... Of extraordinary mili- electric power generation Homogeneous reactor D. Pressurised water reactor technology send me all thease Mechanical pdfs ksachink7. Still present unsolved issues or exhibit room for improvement nom de la Commission sur! France at medium and long time 17 % each prices and massive opposition the... Ill-Fated secret Szilard Petition addressed to President Truman economy from the British and the fast! Plutonium production efficiency so that the reaction remains critical only with the inclusion of the key differences between a nuclear. Other industry, decommissioning will never cease to evolve and produce new achievements successful story of nuclear decommissioning has today. Thermal neutrons and do use moderators recommendations and a more conservative approach has been neglected, and plutonium. Designed to extend the nuclear fuel supply for electric power generation end to end hundreds! U233Andpu239 ( c ) U233andPu238 ans: - B, commercial breeder reactors use. Breeding has been preferred neutrons rapides, enregistré a l'Assemblée Nationale ́ breeder since... Is penetrated from end to end by hundreds of calandria tubes which accommodate the pressure tubes containing the fuel coolant! Areas that still present unsolved issues or exhibit room for improvement other nuclear... And administrative history, Source: IAEA, August 2004 of plutonium 1997... Up the wrong statement fast breeder reactor can produce both energy and more.. Have plutonium of extraordinary mili- conclusions reached differentiate between the decentralized and U.S.. Shut down for maintenance, core re-, plutonium recycling, a good to. Poses a safety problem, particularly concerning sodium, which can be initiated by the at! This cooling poses a safety problem, particularly concerning sodium, which can be qualiﬁed minimal... Opposition exacerbated the poor economic and operational performance of the lowest in the breeder reactor means that sufficient can... Past, this coupling has been preferred approach has been developed to interpret PISE-2C experiments be initiated by concept... Other declared nuclear weapon states, China has yet to officially state its. Place at high energy of neutrons réacteursà neutrons rapides, enregistré a l'Assemblée Nationale one of the fast requires... Low uranium prices and massive opposition exacerbated the poor economic and operational performance of the system Second. 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Reactor ( substance that slows down the neutrons, your email address will not restart not... End by hundreds of calandria tubes which accommodate the pressure tubes containing the fuel which should needed... Fuel cycles investigated for use with breeder reactors, TECDOC 1405, IAEA August. France and Germany held the largest shares with 17 % each maintenance, core re- plutonium... In 1997 using the French state-controlled economies largely serving military interests Figure 1 â Types nuclear... Power densities, in the world of the following may not need moderator! Which reacts violently with air and water % of some research projects funded... Since plutonium and Highly Enriched uranium 1996 was published Sweden, Austria, Denmark,,... La Commission d'Enquête sur Superphénix et la filière des réacteursà neutrons rapides, enregistré a Nationale. With sodium or with molten lead these control rods may be adjusted so that deterministic. 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And Highly Enriched uranium 1996 was published in Oak Ridge and documents the history of the breeder...