静叶轮毂间隙对高负荷压气机性能的影响研究

Research on the Influence of Stator Hub Gap on the Performance of High-Load Compressor

静叶轮毂间隙的改变显著影响轴流压气机的气动性能。本文以某1.5级高负荷轴流压气机为研究对象,采用经过校核的三维稳态数值模拟方法探究静子轮毂间隙大小和尾缘间隙长度对其气动性能的影响。研究发现:原型压气机在近失速工况点,静子近轮毂区域吸力面发生流动分离,导致流动堵塞,引发压气机失速。随着轮毂间隙的增加,压气机的失速裕度先迅速增加后缓慢减小,峰值效率下降。在峰值效率工况点,原型静子近轮毂区域的流动整体良好,吸力面分离较小,轮毂间隙反而使得泄漏流增多,泄漏损失增加。而尾缘间隙相比于轮毂间隙,其对压气机的峰值效率恶化较小。随着尾缘间隙长度的增加,轮毂泄漏流增多,有效抑制了静子吸力面附近低能流体的堆积,改善了近轮毂区域的流场,提升了压气机的失速裕度。

The change of the stator hub gap significantly affects the aerodynamic performance of the axial compressor.This paper takes 1.5-stage high-load axial compressor as the research object,and uses the validated three-dimensional steady-state numerical simulation method to study the influence of the stator hub gap size and trailing edge gap length on its aerodynamic performance.The study found that near the stall point of the prototype compressor,flow separation occurred on the stator suction surface near the hub region,which caused flow blockage and triggered the compressor stall.As the size of the hub gap increases,the stall margin of the compressor increases rapidly,then slowly decreases,and the peak efficiency decreases.At the peak efficiency point,the flow of the prototype stator near the hub region is good,the flow separation of the suction surface is small,but the hub gap increases the mass flow of leakage flow and the leakage loss.Compared with the hub gap,the trailing edge gap has less effect on the peak efficiency of the compressor.As the length of the trailing edge gap increases,the leakage flow of the hub region increases,which effectively suppresses the accumulation of low-energy fluid near the suction surface of the stator,improves the flow field near the hub region,and thus improves the stall margin of the compressor.