Integrated researches of topical problems of fast reactors thermal physics

Abstract

The results of actual studies are presented to justify the thermophysical characteristics and safety of fast reactors with sodium and lead coolants. The influence of a stratified coolant flow on the formation of velocity and temperature fields in a fast reactor vessel with a sodium coolant is shown. The development of the degradation of the fuel assembly during the development of a severe accident with the loss of sodium flow rate in a fast reactor, the blockage of the cross sections of the fuel assembly and the release of marker materials beyond it are demonstrated. The expediency of the combined sodium purification system built into the reactor vessel is shown, in which “cold traps” are an indispensable element, and “hot traps” provide accelerated oxygen purification during operation of the NPP in nominal regime. The results of studies of a large-modular sodium-water steam are presented. As applied to a reactor with a lead coolant, the influence of spacer grids on heat transfer in a fuel assembly of the core is shown. On the model of the steam generator of the reactor installation with lead coolant, it was found that the values of the steam temperature at the outlet of both collectors coincide. The temperature of lead at the exit from the lowering section and in the main path of lead is coincides also. The state and prospects of the development of technology for heavy liquid metal coolants are analyzed. The principle possibility of providing the required parameters of a high-temperature fast reactor with a sodium coolant for the production of hydrogen is shown. The problems of further thermophysical research are analyzed.