Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

The occurrence of a PTS in a reactor vessel is an important phenomenon for assessing nuclear reactor safety. New experiment was conducted at HZDR, focused on thermal mixing processes in the cold leg and the downcomer of two-phase PTS case. Present work reports CFD analysis of steady-state air-water case. CFD analysis was conducted with two turbulence-modeling approaches, RANS and LES. Multiphase situation was modeled with VOF approach. Simulations were performed using the ANSYS Fluent 12 package. Comparison of computed temperatures results and measurements along the thermo-couple lines revealed results depend on the turbulence model used.