COMPLEX FLUID FLOW IN POWER NUCLEAR REACTORS CORE; CASES OF BWR, PBMR AND HTR-PM

Abstract

In this work, the technology of PBMR, HTR-PM and BWR as well as the nuclear reactor core constitution with fuel elements arrangement are presented. The mathematical part: conservation equations for continuity, momentum and energy as well as equations of state and boundary conditions, for both porous media theory and two-phase flow theory are developed and applied to each type of nuclear reactor. For the case of the HTR-PM and PBMR nuclear reactors, two approaches cases are applied. The first approach is the study of a channel saturated with a porous medium consisting of fuel spheres and cooled by an inert gas, this to approach the HTR-PM. The second is an application for a case of porous medium consisting of the same fuel spheres but arranged in an annular domain to approach the PBMR. For the case of BWRs, a nuclear thermalhydraulic channel is defined and the different two-phase flows presented. The same set-up equation is applied except that it is written for each phase and for the interface between the two phases, the specific case of annular two-phase flow is studied. The obtained results, presented in figures and physically analyzed, are very satisfactory. It can thus be concluded that applying the model of porous media and the two-phase flow one for complex flows respectively for PBMR, HTR-PM or BWR power nuclear reactors core can ensure a well behavior of the nuclear reactor core thermalhydraulics. Some of presented results in this paper were published or under full publication.