湿蒸汽两相流动的非定常数值模拟

Unsteady Numerical Simulation of Wet Steam Two-phase Flow

应用两相均质混合模型、湿蒸汽平衡相变模型以及双时间步长法,对某超临界汽轮机末级叶栅流场进行了全三维非定常的数值计算。计算结果表明:湿蒸汽流动与流场内的非定常特性密切相关,其定常计算结果与非定常的时均结果不相一致。由于动静叶干涉的影响,动叶栅出口由非定常计算得到的湿度值小于定常计算得到的结果。

Employing two-phase homogeneous mixture model, the equilibrium phase change model and the dule time step method, the flow field of last stage in a supercritical turbine was solved by 3D unsteady numerical simulation. The result is indicated that wet steam flow is closely related to the unsteady characteristic of the flow field. It is also noted that the steady result is different from that of the time-averaged unsteady computation. Due to the interaction of the stator-rotor interface, the liquid mass flow of the unsteady calculation at the rotor exit is less than that of steady calculation.