Research On The Method Of Making Consistent P_N Scattering Cross Section For Fast Reactors

Because fast reactors can greatly improve the utilization efficiency of uranium resources and the advantages of the transmutation long life nuclear waste,it is attracting more and more attention internationally.In fast reactor physics calculation,the anisotropy of neutrons is stronger due to the high neutron energy.It is of great significance to generate broad group cross section,which considered anisotropy modification,used for fast reactor calculation.This thesis created 2082 groups hyperfine group neutron cross section in each nuclide based on ENDF/B-?.1 evaluation nuclear data library,then created cross section for lead cooled fast reactor RBEC-M and sodium cooled fast reactor ZPR6A7 using independent research and development fast reactor multi group cross section generation code MGGC,and then did tested and validated.In order to produce the consistent broad group cross section of 230 groups,a consistent PN method module was built into the MGGC code to solve the neutron transport equation.The main function of this module is solving consistent PN equation,at the same time,considering the influence of the geometric effect to the energy spectrum by using the leak correction method,and achieved consistent neutron flux density and flux moment,and produce consistent neutron cross section using the neutron flux density and flux moment.At the same time,MGGC also can set different temperatures for different nuclides in a region to solve the temperature consistent problem in the cross section production process.In order to verify the feasibility and accuracy of the method of fast reactor cross section generation,the thesis uses the international lead cooled fast reactor benchmark RBEC-M and the sodium cooled fast reactor benchmark ZPR6A7.The results show that the Keff results of 230 groups multi group cross section only has about 57 pcm difference compared with the results of cosRMC for the RBEC-M benchmark.The maximum deviation of the power calculation result of the lead bismuth RBEC-M is about 0.5%,and the maximum deviation of the core power calculation of ZPR6A7 benchmark is slightly larger,which is about 4.5%.For the above two benchmarks,consistent P1,consistent P,extend N and consistent PN approximation have the same calculation accuracy.To sum up,the proposed fast reactor cross section generation method is feasible,using NJOY and independent development fast reactor cross section generation code MGGC can generate cross section which has high precision,and more benchmark will be used to verify the engineering applicability of MGGC in the future.