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Information × Registration Number 0223U005386, 0122U001511 , R & D reports Title Development of power control methods for the perspective fast reactor with a wave of nuclear burning and modeling of materials for nuclear power of the next generation popup.stage_title Head Bakai Oleksandr S., Доктор фізико-математичних наукShulha Mykola F., Доктор фізико-математичних наук Registration Date 22-12-2023 Organization National Science Center "Kharkiv Institute of Physics and Technology" popup.description2  1. We developed a computer program that calculates the equation of nuclide transmutation under the influence of a variable neutron flux to study the dependence of the averaged microscopic cross section (AMCS) of fast neutron capture by nuclear fission products on the neutron fluence in a nuclear burning wave (NBW) reactor. The linear dependence of AMCS on the neutron fluence was found and its parameters were determined. The study of the NBW phenomenon in this work was performed using the original FANTENS-2D computer code, which was modified to take into account the change of AMCS of the fission products with the level of fuel burnout. We made calculations of the NBW motion at a given power (which is set by ajusting the concentration of the Ta-181 neutron absorber in the radial reflector), both taking into account the AMCS dependence on the level of fuel burnout and neglecting it. It is shown that the change of AMCS of the fission products demands the increase of the amount of neutron absorber, which must be added to the radial neutron reflector to stabilize the NBW reactor power at a given level. 2. Based on the experimental data for the 5BaO∙8SiO2 (B5S8) model glass, the rate of crystal nucleation and growth was calculated as a function of the degree of structural relaxation and temperature. It is shown that glass relaxation and its temperature dependence must be taken into account when determining the possibility and rate of crystallization in glasses used for RAW vitrification. We demonstrate that glasses with a high crystallization rate, such as stoichiometric barium silicate B5S8, may not reach the final steady state of crystal nucleation at temperatures below the glass transition threshold, but may fully crystallize earlier. Taking into account the relaxation by one parameter within the classical nucleation theory allows to derive the crystalline phase volume fraction, its growth rate and the average crystal size. Product Description popup.authors Abyzov Olexander S Bakai Oleksandr Stepanovych Borysenko Oleksandr O. Davydov Leonid M. Lazarev Mykola P. Malovytsia Maksym S. Pilipenko Volodymyr V. Turkin Anatoliy A. Fomin Serhii P. Shulha Mykola F. popup.nrat_date 2023-12-22 Close