带进汽腔体的整圈斜置静叶的数值研究

Numerical Simulation on Full Circle Skew Stator with Inlet Annulus

基于某超超临界机组的汽轮机中压缸数据,对带进汽腔体的整圈斜置静叶进行了数值模拟.通过对进口流动角度的分布、不同周向位置叶片的表面压力分布、相对应的速度矢量图和压力云图以及斜置静叶下游流动参数的分析,研究了进汽腔体所带来的周向不对称性对下游叶片流动的影响,以及上游的周向不均匀性经过斜置静叶后的变化.结果表明:进汽腔周向进气的不对称性使周向进气角有偏差,导致冲角沿周向产生较大波动;气流经静叶之后,周向不均匀性会减弱.在设计第一级静叶时,应选择对来流进气角度不敏感的翼型.

Based on the data of the intermediate pressure （IP） cylinder in an ultra supercritical steam turbine, numerical simulation for the full circle skew stator with inlet annulus was carried out. The effect on the flow of downstream blade by circumferential asymmetry due to inlet annulus and the development of circumferential asymmetry flowing through the skew stator was studied through analyzing the flow angle distribution at the inlet, blade surface pressure distribution at different circumferential positions, the corresponding velocity vectors and pressure contour, and the downstream flow parameters of the skew stator. Results show that there is some deviation to the circumferential inlet angle due to the asymmetry of that in the inlet annulus. Thus the incidence will have higher fluctuation along the direction of circumference. The uneven stream distribution along circumference will weaken after the stream flowing through the stator blade. The profile which is insensitive to the inlet angle of inflow should be selected in designing the first stage of the stator blade.