轴流压气机可调静子叶片间隙泄漏流数值研究

为了探究轴流压气机前面级可调静子叶片部分间隙泄漏流对压气机性能和流场的影响,通过数值方法模拟某轴流压气机带有可调静子叶片的前面级1.5级流场,并详细分析了部分间隙泄漏流特征。数值仿真结果表明,相较带容腔原型算例,部分间隙使得压气机特性线往左下方偏移,设计点效率降低0.12%,近失速点效率降低1.83%,但喘振裕度提升6.4%；可见受到部分间隙泄漏流影响,静子叶片根部出口气流角明显增加；部分间隙泄漏流可以给吸力面根部角区低能流体充能,降低设计点端壁处的损失,降低近失速点吸力面分离涡的强度,提升喘振裕度；根部部分间隙造成叶片根部做功能力降低,但影响范围控制在5%叶高以内；部分间隙造成静子根部流场发生改变,使得设计工况点静子根部产生一条附着线,并形成闭式分离。

Numerical Simulation Research on the Clearance Leakage Flow of the Variable Stator Vane from an Axial Compressor

To investigate the influence of the variable stator vane partial gap of the axial compressor front stage on the performance of the compressor and the flow field,numerical simulation was carried out on the front 1.5 stage axial compressor consisted of a variable stator vane, and the detailed analysis was conducted on the flow characteristics of the partial gap leakage flow. The numerical simulation results show that the performance curve shifts downwards and left due to the effect of the partial gap compared with the prototype cavity case. The efficiency decreased 0.12% at the design point (DP) working condition and 1.83% at the near stall (NS) working condition respectively and the stall margin (SM) increased 6.4%. The outlet flow angle of S3 at the hub region increased due to the partial gap leakage flow. The partial gap leakage flow can charge the low momentum fluid at the hub corner region, therefore, the total pressure loss coefficient decreased at DP working condition. The separation vortices at the suction side can be weakened by the partial gap leakage flow and the stall margin will be improved. The blade can not provide sufficient working capacity but the range is limited below 5% span. The flow field at the hub region changed due to the partial gap, an attachment line formed at the hub region at the suction side and involved into closed separation.