Application of Streamline Curvature Method for Multistage Transonic Axial Compressor Performance Prediction

In order to study the multistage transonic compressor analysis issue, a throughflow method based on the general throughflow theory and streamline curvature (SLC) approach is presented to calculate the internal flow fields and the performance of transonic axial compressors. The approach includes some semi-empirical correlations established based on previous literatures, such as minimum loss incidence angle model, deviation model and total pressure loss model. In order to improve the prediction accuracy of the semiempirical model, considering the complex three-dimensional flow effect in the real compressor, some reasonable modifications were made for some early models, including a revised deviation model applied to the cascade with large deflection range, as well as a more reasonable prediction model of variable structure shock loss. Two transonic compressors are calculated and verified, and the calibration results are compared with the experimental results and three-dimensional numerical calculation. The comparison shows that the maximum prediction errors at design condition for total pressure ratio and efficiency are 4.1% and 1.1%, respectively. Characteristic prediction and the spanwise flow field parameters can also be calculated in line with the experimental value of the trend at the non-design conditions. In general, this computational method can be used to predict the performance of modern transonic axial multistage compressor.