汽轮机末级静叶栅内非平衡态凝结流动的数值研究

Numerical Research on Non-equilibrium Condensation Flow in Steam Turbine Last Static Cascade

对非平衡态凝结的末级静叶栅流场进行了数值研究。在三维CFD计算中加入双流体模型,并将其流场与平衡态的凝结流场进行了对比。对比内容包括叶片表面压力分布、马赫数分布以及成核率、湿度等参数。对比结果表明:双流体模型能够更为准确地描述叶栅内存在的非平衡态凝结流动,成核率和凝结区面积沿叶高方向逐渐减小。

In this paper, a numerical study on the flow field of the last stage static cascade with non-equilibrium condensation is carried out. A newly developed dual fluid model is added to the three-dimensional CFD calculation, and the flow field is compared with the condensed flow field of the equilibrium state. The contrast content includes the pressure distribution of the surface of the blade, the distribution of Maher number and the parameters of the nucleation rate and humidity . The comparison results show that the two fluid model can more accurately describe the non-equilibrium condensation flow in the cascade, and the nucleation rate and the area of condensation area decrease gradually along the direction of the leaf height.