离心压气机顶部进口条件对叶轮内部流动的影响

对于带分流叶片的离心式压气机叶轮,在顶部边界层亏损和喷气等进口条件下对叶轮内部流场进行了CFD数值模拟,对比分析了进口喷气处理对改善内部流动、提高稳定性的机理。结果显示:在进口叶顶附近进行喷气处理时,顶部间隙涡流得到了有效地控制,且降低了间隙损失的发生,有助于提高流动的稳定性,但在下游区域这种作用逐渐减弱和消失。同时,进口条件的不均匀性对内流有一定的影响,精细的CFD分析应当计及这种因素。

THE INFLUENCE OF INLET CONDITION NEAR SHROUD ON INTERNAL FLOW OF CENTRIFUGAL COMPRESSOR IMPELLER

The CFD simulation has been accomplished for a centrifugal compressor impeller with splitter, under the inlet conditions of boundary-layer deficit and jet flow respectively, near shroud of the impeller. The analysis and the comparison show that entrance jet flow at tip of the impeller can significantly decrease clearance vortex and demonstrate stabilization to clearance flow. However at down-stream, this effect becomes weakened and even disappeared. The uniformity of inlet flow condition has significant influence on internal flow of impeller during CFD simulation. It is necessary to take this effect into account when delicate simulation result is important.