特性叠加法对双级离心压气机试验的分析应用

Analysis and Application of Characteristic Superposition Method to a Double-Stage Centrifugal Compressor Test

完成了某双级离心压气机的试验特性录取,在各分级特性满足指标要求的情况下,双级试验设计点性能明显低于设计指标。对比各级在双级中的特性以及在双级中的匹配特征发现:双级中的进口级性能与单独进口级吻合较好,而出口级径向扩压器叶顶与盖板采取的压紧连接方式,因高温、高压变形会产生较大的间隙泄漏损失,使得出口级性能恶化并导致双级离心提前喘振,这在叠加双级特性结果的对比中得到了进一步确认。

The test performance of a double-stage centrifugal compressor has been finished, and the double-stage test characteristics in the design point is obviously lower than the design target in the condition of filling the requirement of every single stage. Through the contrast of single-stage performance and the matching relations in the combined compressor, we could get a result that the inlet-stage performance in the double stage primely accords with the single inlet-stage, and because the blade tip in the radial diffuser of the outlet stage was impacted tightly into the cover, a big gap was appeared as a result of serious distortion in the condition of high pressure and high temperature. However, the contrast between the self double-stage performance and the superpositioned results further confirmed that the tip clearance would produce a bigger tip leakage loss, which will worsen the outlet-stage characteristics and push the double stage into the surge state ahead.