雷诺数对轴流风扇/压气机性能和稳定性的影响

Effects of Reynolds Number on Performance and Stability of Axial Fans/Compressors

介绍了一种预估轴流风扇 /压气机特性和不稳定边界的方法。该方法采用考虑雷诺数影响的“基元叶栅法”计算轴流风扇 /压气机特性 ,并利用 C.C.Koch提出的“有效静压升系数法”预估轴流风扇 /压气机的不稳定边界。为了验证方法的可行性 ,本文模拟了从地面到 2 0 0 0 0 m高空的雷诺数变化 ,对一个五级高压压气机在不同雷诺数下的特性及稳定性进行了计算分析。计算结果表明 ,轴流压气机的特性和稳定性都随雷诺数的降低而下降。

A method to predict the effects of Reynolds numbers on the performance and stability of axial fans/compressors is introduced. The calculation of the performance is implemented by stacking the performances of cascades, and the estimation of the stability is done by estimating the maximum pressure rise potential of axial compressor stages. Both the performances of cascades and the maximum pressure rise potential of axial compressor stages are experimentally got and corrected including the effects of Reynolds number. To validate the methods, the variation of performances and stability of a five-stage compressor in an extensive range of Reynolds numbers are estimated. Reynolds numbers are selected according to the variation of pressure, temperature and density of air at deferent altitudes to simulate the working atmosphere of aeroengine. Results prove that the performance and stability of compressors deteriorate with the decline of Reynolds number. The improvement of the performance and stability by increasing blade chord length is mentioned.