Improving the effectiveness of radiation protection during transportation and storage of spent fuel
Rudychev Volodymyr H.,
V.N. Karazin Kharkiv National University
To study the impact on the protective properties of various materials for thicknesses that are similar to the characteristics of the HI-STAR 190 UA transport container, the MCNP and PHITS software packages have developed simplified models of protection: a) flat multilayer (6 layers, more possible) protection in the form discs, disc diameters and their thicknesses and materials may vary; b) a simplified model of multilayer (6 layers, more possible) cylindrical protection, the thicknesses and materials of the layers may vary. These models make it possible to optimize thicknesses, materials and the order of placement of radiation protection layers for both gamma radiation and neutrons of spent nuclear fuel.
The yields and spectral distributions of gamma quanta of long-lived radionuclides of spent fuel after passing through protections with Fe, Pb, U, UO2 were calculated. A comparison of the effectiveness of protection from heavy elements with protection from steel is carried out. Calculations were made of the change in the spectrum of SNF neutrons created by 244Cm when passing through Fe and Pb shields of different thicknesses.
Options for minimizing neutron radiation due to various options for loading VTVZ with different levels of burnout are considered. Loading of container 31 VTVZ with a burn-up of 40.5 MW×day/tU was considered as a rationing option.
For the purpose of transportation safety, a three-dimensional model of the container has been developed for the analysis of heat transfer and cooling processes of spent fuel with different levels of burnout both inside the sealed basket and through the elements of the protection structures against gamma radiation and neutrons.
An engineering model of the combined protection of the transport container based on elements with a large atomic number and reduced density while observing the geometric and weight characteristics of the transport container was developed.
Alekhina Svetlana V.
Hirka Ihor O.
Kovtyn Volodymyr E.
Makhnenko Halyna V.
Pyshkin Volodymyr Borysovich