冲角对不同掠型压气机叶栅扩压因子的影响

对直、前掠、弯掠和后掠叶片组成的压气机叶栅进行了实验研究，结合叶栅出口能量损失分布和叶片表面静压系数的分布及叶片负荷的变化，讨论了冲角变化对不同掠型压气机叶栅扩压因子的影响以及叶栅扩压因子与叶栅能量损失和叶片负荷的相互关系。结果表明，前掠和弯掠叶栅显著改善了叶栅根部的流动．能够有效防止气流减速造成流动分离的可能；这两种叶栅轴向逆压梯度长度和叶片负荷大小的综合作用是其扩压因子在叶片两端部小于直叶栅的原因。

The Impact of the Variation in Incidences on the Diffusion Factor of Compressor Cascades of Different Swept Types

An experimental investigation was conducted of the compressor cascades composed of straight, swept-forward, swept-curved and swept-back blades. In connection with the energy loss distribution at the cascade outlet, the static pressure distribution at the blade surface and blade loading discussed are the influence of variation in incidences on the diffusion factor of compressor cascades of different swept types as well as the interrelationship between the cascade diffusion factor and cascade energy loss on the one side and the blade loading on the other. Study results have shown that the swept-forward and swept-curved cascades markedly contribute to the improvement of flows at the root portion of the cascades, thus effectively eliminating the possibility of flow separation caused by a flow speed reduction. The combined action of a greater reverse-pressure gradient of the above two types of cascade and a lower blade loading at midspan has resulted in a smaller diffusion factor at the two ends of the blade than that at the straight cascade.