汽轮机静叶除湿方法的数值研究

Study on Numerical Simulation of Steam Turbine Dehumidification

本文针对蒸汽轮机末级湿蒸汽形成现象,分析湿蒸汽非平衡凝结流动的控制方程及物理模型。对Moses and Stein喷嘴进行了计算分析,得出湿蒸汽形成过程的特点,并与实验结果相比,契合度可以证明数值计算模型及方法的正确性。最后对某汽轮机静叶进行数值计算,分析湿度及过冷度分布,提出一种新型的静叶除湿结构,并对除湿效果进行计算分析。结果表明,随着通道直径的增加,静叶出口位置的平均湿度降低,湿汽损失减小。

The research, analyzed the governing equations and physical models of wet steam non-equilibrium condensation flow, carried out a numerical calculation on the Moses and Stein nozzle and the correctness of the numerical calculation is proved by comparing with the experimental results which is mainly aiming at the wet steam formation phenomenon in the last stage of the steam turbine.Besides, a fresh dehumidification structure was proposed and the numerical calculation was performed based on a specific steam turbine after analyzed the distribution of wetness and supercooling. The results show that： as passage diameter increasing, both of the average wetness in the outlet position of the stator and the wetness loss decrease.