Numerical investigation on wet steam non-equilibrium condensation flow in turbine cascade

Based on the two-phase wet steam flow with spontaneous condensation, experimental verification and flow analysis on nozzle and 2D cascade are carried out. The 3D Reynolds-Averaged gas-liquid two-phase flow control equation solver is explored with k-epsilon-k(p) turbulence model. Furthermore, 3D flow numerical simulation on the last stage stator of the steam turbine is carried out. The results show that a sudden pressure rise on blade suction surface is mainly caused by the droplet growth in condensation flow. The more backward the condensation position is in cascade passage, the less the sudden pressure rise from condensation is, and the larger the nucleation rate is, the maximum under-cooling and the number of droplets per unit volume are. Interaction of condensation wave and shock wave has imposed greater influence on the parameters of the blade cascade outlet.