The occurrence of a PTS (pressurized thermal shock) in a reactor vessel is an important phenomenon for assessing nuclear reactor safety. New experiment was conducted at HZDR (Helmholtz-Zentrum Dresden-Rossendorf),...The occurrence of a PTS (pressurized thermal shock) in a reactor vessel is an important phenomenon for assessing nuclear reactor safety. New experiment was conducted at HZDR (Helmholtz-Zentrum Dresden-Rossendorf), focused on thermal mixing processes in the cold leg and the downcomer of two-phase PTS case. Present work reports CFD (computational fluid dynamics) ana|ysis of steady-state air-water case. CFD analysis was conducted with two turbulence-modeling approaches, RANS (Reynolds Averaged Navier-stokes) and LES (large eddy simulations). Multiphase situation was modeled with VOF (volume of fluid) approach. Simulations were performed using the FLUENT 12 package. Comparison of computed temperatures results and measurements along the thermo-couple lines revealed results depend on the turbulence model used.展开更多
文摘The occurrence of a PTS (pressurized thermal shock) in a reactor vessel is an important phenomenon for assessing nuclear reactor safety. New experiment was conducted at HZDR (Helmholtz-Zentrum Dresden-Rossendorf), focused on thermal mixing processes in the cold leg and the downcomer of two-phase PTS case. Present work reports CFD (computational fluid dynamics) ana|ysis of steady-state air-water case. CFD analysis was conducted with two turbulence-modeling approaches, RANS (Reynolds Averaged Navier-stokes) and LES (large eddy simulations). Multiphase situation was modeled with VOF (volume of fluid) approach. Simulations were performed using the FLUENT 12 package. Comparison of computed temperatures results and measurements along the thermo-couple lines revealed results depend on the turbulence model used.