考虑轴向间距变化的低速压气机Clocking效应的数值模拟

以低速压气机试验为原型,采用二维非定常数值模拟的方法研究了轴向间距改变对低速压气机气动性能的影响。数值模拟结果显示,轴向间距减至原型间距的33%时,整机效率的提高超过了1%。该方案在除第一列静叶之外的三列叶栅中都表现出流动损失的降低,尤其在第一列动叶中最为明显。轴向间距减小带来的势流干扰增强产生非定常的扑翼现象,显著改善了第一列动叶的流动状态。适当减小轴向间距可以降低叶栅内下游叶列非定常干扰引起的损失。

Numerical study on the clocking effect of a low-speed compressor with different inter-blade-row gaps

Based on the experimental results of a low speed compressor,two-dimensional(2D) unsteady numerical simulation has been applied to study the performance variation of low speed compressor with different inter-blade-row gaps.The result of simulation shows that the compressor efficiency is increased by more than 1% when the axial gap is decreased to be 33% of the original gap.Except for the first static row,the flow losses in the rear three blade rows are all reduced,obviously in the first rotor row in this case.It is analyzed that the enhancement of potential disturbed flow caused by the axial gap reduction will produce an unsteady flapping wing phenomena,which improves the flow significantly in the first rotor row.The conclusion is given that properly decreasing the axial clearance can reduce the loss of downstream blade row caused by unsteady disturbances.