[en] The mode of fuel management of the HTR-10 was studied, including the simulation of the fuel shuffling process and the measurement of the burnup of a fuel element. The prior consideration was the design of the equilibrium state. Based on this the fuel loading of the initial core and the fuel shuffling mode from the initial core through the running-in phase into the equilibrium state were studied. The code system VSOP was used for the physical layout of the HTR-10 at the equilibrium state and in the running-in phase. For the equilibrium state, in order to lessen the difference between the peak and the average burnup, 5-fuel-passage-through-the-core was chosen for the fuel management. The average burnup of the spent fuel for the equilibrium core is 80000 MWd t^-1, and the peak value of it is less than 100000 MWd t^-1 when the burnup of the recycled fuel element is under 72000 MWd t^-1. The mixture of fuel element and graphite element was used for the initial core loading, the volume fractions of the fuel and the graphite elements were 0.57 and 0.43, respectively. During the running-in phase, the volume fraction of graphite will decrease with the fresh fuel elements being loaded from the top of the core and the graphite elements discharged from the bottom of the core. The fuel shuffling mode is similar to that of the equilibrium state. The burnup limit of recycled fuel element is also 72000 MWd t^-1 and the peak burnup is less than 100000 MWd t^-1. Finally the core will be full of fuel elements with a certain profile of burnup and reaches the equilibrium state. According to the characteristics of the pebble-bed high temperature gas-cooled reactor, a calibrating method of concentration of ¹³⁷Cs was proposed for the measurement of fuel burnup

No abstract available

[en] The mathematical model for simulating the transient under loss of primary flow of liquid metal fast breeder reactor (LMFBR) is presented. Based on this model, a computer code FRLOF is encoded. Using the code, the authors have simulated two transients of EBR-II. The calculated and the measured results are all in good concordance

[en] The application of probabilistic risk assessment for fusion-fission hybrid reactor is introduced. A hybrid reactor system has been analysed using event trees. According to the character of the conceptual design of Hefei Fusion-fission Experimental Hybrid Breeding Reactor, the probabilities of the event tree series induced by 4 typical initiating events were calculated. The results showed that the conceptual design is safe and reasonable. through this paper, the safety character of hybrid reactor system has been understood more deeply. Some suggestions valuable to safety design for hybrid reactor have been proposed

[en] It is studied from the point of view of neutronics that feasibility of transmutation for transuranic isotopes of the PWR-(U)-Spent-Fuel including ²³⁸Pu, ²³⁹Pu, ²⁴⁰Pu, ²⁴¹Pu, ²⁴²Pu, ²⁴¹Am, ²⁴³Am and ²⁴⁴Cm in the Fast-Fission-Blanket of Fusion-Fission Hybrid Reactor. The neutron transport and burnup of four Fast-Fission-Blankets with various fuel composition has been calculated and analyzed using the one-dimension-neutron-transport-and-burnup-calculation-code BIDECAY. The results show that it is possible to transmute the transuranic isotopes of the PWR(U)-Spent-Fuel with reliable safety and high efficiency in the Fast-Fission-Blanket of Fusion-Fission Hybrid Reactor

[en] The disposal of the high level radioactive waste (HLW) is related to the development of nuclear energy and the protection of the environment. In the world, the partitioning and transmutation, one of the possible ways to dispose of HLW, has almost a three-decade-history of research and development. At present, it has been concerned more and more by people. Introduced respectively are the principle, research and development, and prospect which are about the transmutation of HLW using LWR, LMFR, fusion reactor (fusion-fission hybrid reactor), and accelerator-driven subcritical system. Some suggestions are proposed for China to launch the study of transmutation

[en] The 10 MW High Temperature Gas-cooled Reactor-Test Module (HTR-10) is a pebble bed experimental reactor built by the Institute of Nuclear Energy Technology (INET), Tsinghua University. This paper introduces the first critical prediction calculations and the experiments for the HTR-10. The German VSOP neutronics code is used for the prediction calculations of the first loading. The characteristics of pebble-bed high temperature gas-cooled reactors are taken into account, including the double heterogeneity of the fuel element, the buckling feedback of the spectrum calculation, the effect of the mixture of fuel elements and graphite balls, and the correction of the diffusion coefficients in the upper cavity based on transport theory. Also considered are the effects of impurities in the fuel elements, in the graphite balls and in the reflector graphite on the reactivity. The number of fuel elements and graphite balls in the initial core is predicted to provide reference for the first criticality experiment. The critical experiment adopts a method of extrapolating to approach criticality. The first criticality was attained on December 1, 2000. The first criticality experiment shows that the predicted critical number of the fuel elements and graphite balls is in close agreement with the experimental results. Their relative error is less than 1.0%, implying the physical predictions and the results of the criticality experiment are much beyond expectations

[en] Through the analysis of the effect of heavy metal actinides on the effective multiplication constant (k_eff) of the core in accelerator-driven system (ADS) sodium-cooled fast reactor loaded with metallic fuel, we gave the method for determining fuel components. the characteristics of minor actinides (MAs) transmutation was analyzed in detail. 3D burn-up code COUPLE, which couples MCNP4c3 and ORIGEN2, was applied to the neutron simulation and burn up calculation. The results of optimized scheme shows that adjusting the proportion of ²³⁹Pu and maintaining the value during the burn-up cycle is an efficient method of designing k_eff and keeping stable during the burn-up cycle. Spallation neutrons lead to the neutron spectrum harder at inner core than that at outer core. It is in favor of improving MA's fission cross sections and the capture-to-fission ratio. The total MAs transmutation support ratio 8.3 achieves excellent transmutation effect. For higher flux at inner core leads to obvious differences on transmutation efficiency,only disposing MAs at inner core is in favor of decreasing the loading mass and improving MAs transmutation effect. (authors)

[en] In this paper, a computer program FRLOF-2 is presented. With it, we have simulated three transients of EBR-II test (including SHRT 39, SHRT 45, and a LOHS test). The calculated results and the measured preliminary ones are in good concordance. (author)

[en] Studied in the paper is the neutronics feasibility for transmutation of High Level Radioactive Wastes (HLW) ²³⁸Pu, ²⁴⁰Pu and ²⁴²Pu using Fusion-Fission Hybrid Reactor (FFHR) with ²³³U as neutron multiplier. Four conceptual Fast-Spectrum-Blankets (FSB) with various fuel composition are designed. Calculation and analysis for the selected schemes are carried out with transport-burnup code BIDECAY. The results show that with ²³³U as neutron multiplier, the transmutation for ²³⁸Pu, ²⁴⁰Pu and ²⁴²Pu in FSB of FFHR is feasible with reliable safety