FLUID DYNAMICS IN THE CORE OF A WWER REACTOR WITH TVSA OF VARIOUS DESIGNS

The results of experimental studies of the interassembly interaction of coolant in VVER reactor core which consists of TVSA-T and upgraded TVSA are presented. The modeling of coolant flow in the fuel assembly (FA) was carried out on an aerodynamic stand. The studies were carried out on a fragment model of VVER reactor core and consisted in measuring the velocity vector modulus in the characteristic zones of both TVSA and interassembly space of VVER reactor core. The measurements were carried out by a five-channel pneumometric probe. An analysis of the spatial distribution of projections of the absolute flow velocity allowed to detail the pattern of flow-round by the coolant flow of spacer, mixing and combined spacer grids TVSA. The results of study of interassembly interaction of coolant between neighboring TVSA-T and upgraded TVSA were adopted for practical use by JSC “Afrikantov OKBM” in assessing heat engineering reliability of VVER reactor cores and are included in the data-base for verification of computational fluid dynamics programs (CFD codes) and detailed cellular calculation of VVER reactor core.