离心压气机周向槽机匣处理方案的对比分析

Numerical analysis of two circumferential groove casing treatments about a centrifugal compressor

为了提高一带小叶片离心压气机50%设计转速下失速裕度,设计了两套周向槽机匣处理方案,对实壁机匣和处理机匣压气机流场进行了数值模拟分析.计算结果表明:①第一套方案可以使压气机失速裕度提高10%,并且对压气机压比和效率影响很小,没有带来较大的压比和效率损失;②第一套方案对离心叶轮大叶片75%左右轴向弦长前尖部流场的改善是失速裕度提高的主要原因;③第二套方案没有提高压气机失速裕度,主要是由于开槽的位置不恰当和周向槽过深的原因.

In order to extend the stall margin of a centrifugal compressor with splitter blade, two different circumferential groove casing treatments were designed in this paper. The flow fields in compressor with smooth wall and with treated casing were numerically simulated. The results show that the first circumferential groove treated casing extends the stall margin of the centrifugal compressor by 10%, and it also has little influence on pressure ratio and efficiency. The main reason of extended stall margin was that about 75% axial chord of the tip flow field has been improved. The second scheme did not extend the stall margin, because the position of circumferential groove was not accurate, and the groove was too deep.