Research On Streamline Curvature Method For Compressor Performance Calculation

As the most complex part of aero engine, compressor has a trend toward higher stage loadings and lower aspect ratios, with which complicated blading technologies, such as forward-aft swept, circumferential skewed, coupled skewed are generally applied. It is difficult to analyses the intricate flow because of the second flow. How to calculate fast and efficiently the performance of the compressor make a serious challenge to the current method. With the development of high-performance computer and the flow calculation method, 3-D Computational fluid dynamics are widely used. But through flow calculation presented by Streamline Curvature Method(SLC) plays a significant role with unrivaled advantages such as high-speed calculation, design-oriented outputs and the ability to ingrate data of the compressor in existence. Based on the above background, the thesis focuses on the traditional streamline curvature method. The following aspects are included:Research on the history and the developing trend of the SLC, in view of which, a summary of the current special difficulties and improvement method are made.Against a high-loadings and low aspect ratio compressor with a specific test data, the old deviation and loss models are compared. The calculation shows that the original models have a great limitation, based on which, an alternative method expanding the model database is putted forward.Against the widely used forward-aft swept blading, the axial velocity cumulative formulation along the quasi-orthogonal line is derived. The equation revised the question that the radial cumulative line easily crosses the blade passage. Consequently the revised SLC can calculate the impact on the compressor of the forward-aft swept blading in advance. A five stage High Pressure Compressor is calculated and the result is analysed well.Lastly against the spanwise mixing phenomenon in modern high-loadings and low aspect ratio compressor, a method considering the spanwise mixing is presented. The equation modeling the mixing is derived. Consequently the SLC calculation characters authentically the flow in compressor.