进口边界层对采用弯叶片的平面扩压静叶栅流场性能的影响

给定不同型式的进口边界层,在两种不同亚音速条件下对一平面扩压静叶栅的弯叶片流场进行了数值模拟。结果表明弯叶片对扩压叶栅的改善的能力受进口边界层的特征影响。这种影响分为两个方面:(1)边界层厚度的影响和(2)边界层动量损失厚度的影响。边界层越厚或动量损失厚度越大,在低马赫数条件下弯叶片对吸力面角区密流增加越明显,从而更大程度地提高了端区的流动性能,降低了叶栅损失。在高马赫数条件下,若边界层越厚或动量损失厚度越大,角区密流虽变化不大,但因端区损失较大,其性能的提高会给叶栅总性能的改善带来较大的收益。 

Influence of Inlet Boundary Layer on Flow Field Performance of the 2D Compressor Bowed Stator Vane

For several given types of inlet boundary layer,a numerical investigation on flow field of bowed stator vanes under two inlet subsonic Mach numbers was carried out.It was found that the ability of improving diffusion cascade performance was affected by some characteristics of the inlet boundary layer.The characteristics included two aspects:inlet boundary layer thickness and inlet boundary layer momentum loss thickness.When boundary layer is thicker or momentum loss thickness was greater,the flow capacity is evidently increased near end-wall under Mach number 0.2.Consequently,the cascade performance is improved and total pressure loss is reduced near suction corner to a greater extent.Under Mach number 0.7,though the increase of mass flow density is less,because of the high end-wall loss,improvement of end-wall performance will bring more profits to the overall cascade performance.