总压畸变对压气机气动稳定性影响的整环数值模拟

Full Annulus Numerical Simulation of Aerodynamic Stability of Compressor with Total Pressure Distortion

关键词:  压气机  总压畸变  整环  数值计算  气动稳定性

Key words:  Compressor  Total pressure distortion  Full annulus  Numerical simulation  Aerodynamic stability

摘要:

为研究周向进口总压畸变对跨声速压气机气动稳定性影响的物理机制，采用整环三维定常数值计算方法对进口总压畸变条件下的NASA 37号转子进行求解。计算结果表明:周向进口总压畸变导致压气机稳定裕度大幅降低，设计转速时稳定裕度仅为均匀进气时的59%；畸变区与转子旋转速度相同时，位于畸变区的转子叶片进气速度、压力较小，当压气机工作点接近稳定边界时，该区域的叶片会出现叶尖泄漏流前缘溢流和尾缘倒流的现象，同时叶尖区域出现严重的吸力面附面层分离，叶尖泄漏流和吸力面附面层分离共同导致压气机失稳；周向进口总压畸变不会改变失稳的始发位置，但会影响失稳的原因。

Abstract:

In order to investigate the aerodynamic stability of transonic compressor with circumferential inlet total pressure distortion， a full annulus three-dimensional steady simulation of NASA Rotor37 with rotating circumferential total pressure distortion was carried out. The numerical results show that circumferential inlet total pressure distortion reduces the stall margin greatly. The stall margin is only 59% of uniform inlet flow at design speed. The total pressure and velocity under distortion region are lower than other area when distortion region rotates as the same speed of rotor. Tip leakage flow will spillage at leading edge and reverse at trailing edge when operation point closing to stall boundary and suction surface near tip region will come out boundary layer separation at the same time. Both tip leakage flow and suction boundary layer separation make compressor unstable. Circumferential inlet total pressure distortion will not change the position where the instability firstly takes place but the cause of instability can be affected.