„Development of the model of a spent fuel pool based on a porous body approach“

At the Institute of Fluid Dynamics of the Helmholtz-Zentrum Dresden-Rossendorf CFD, methods are developed and applied to determine the evolution of the rod surface temperatures of fuel elements for the case of evaporation or leakage of the storage pool. The aim of the investigations is to identify global flow circulations and to analyze their effect on the coolability of the individual fuel elements. Different loading conditions, i.e.  distances between fuel assemblies, fuel age (different energy release) or partial loading are considered. The application of CFD for this problem is possible, but the geometric resolution of the individual cooling channels in the fuel elements exceeds the degree of realizable effort. A spatial averaging is performed by modeling the fuel elements as porous bodies. The heat transfer to the cooling medium and the flow pressure loss are represented by appropriate source and sink terms. Small scale simulations at the Institute of Fluid Dynamics at the TU Dresden help to parameterize the model accordingly. The experimental analyses at the participating research institutions form the basis for validation.