一种压气机过渡态叶尖径向间隙控制方法研究

A tip clearance control method study of compressor in transient state

在发动机工作条件下,压气机机匣热响应通常比转子热响应更快,这种特点会导致过渡态压气机转、静子热变形不匹配,尤其是压气机后几级。通过减缓压气机机匣热响应的叶尖间隙控制措施,可有效降低过渡态对压气机后几级叶尖径向间隙的影响。以某压气机为例,采用在机匣局部增加质量的方式提高机匣热容,可起到减缓过渡态机匣热响应的作用。理论计算表明,过渡态叶尖最小间隙可增加约0.17 mm,进而可以降低叶尖转、静子碰磨风险或允许减小叶尖间隙;最大间隙减小约0.24 mm,进而可以提高发动机效率和安全性。该叶尖间隙控制结构可供工程设计参考。

In general,the thermal response of the compressor casing is faster than that of the rotor under the working condition of the engine,which will lead to the mismatch of the thermal deformation of the rotor and stator in the transient state,especially in the latter stages of the compressor.The tip clearance control measures to slow down the thermal response of the compressor casing can effectively reduce the influence of the transient state on the tip radial clearance of the compressor latter stages.The casing of a compressor was taken to improve the heat capacity by increasing the local mass so as to slow down the transient thermal response.The theoretical calculation shows that the transient minimum tip clearance can be increased by 0.17 mm,which can reduce the collision risk of blade tip and casing or allow to reduce the tip clearance.The maximum clearance can be reduced by 0.24 mm which can improve the efficiency and safety of the engine.The tip clearance control structure can provide reference for engineering design.