CFD Simulations of Buoyancy Driven Flow Mixing Experiments Performed at the ROCOM Facility

Abstract

Multi-physics approaches are currently developed at Tractebel Engineering (TE) for accurately simulating the complex interaction between neutronics and thermal-hydraulics during asymmetric accidents. One branch of the improvements of the method focuses on the implementation in the coupled codes package of realistic core inlet distributions obtained from CFD results. Two flow mixing tests performed at the ROCOM facility and representative of asymmetric flow conditions are being simulated with the CFD code ANSYS CFX 12.0. The results show that the main mixing phenomena are qualitatively well reproduced, but a quantitative analysis points out an underestimation of the mixing in the simulations.