Based on axisymmetric S2 stream surface theory

a streamline curvature throughflow method is presented in this paper.Improvements on streamline curvature calculation and relaxation factor determination were made

which enhanced the convergence

stability and precision of this method.Asimple blade force handling method was also proposed for computing flow field in the blade passage.At the same time

a bypass compression system computational method was integrated

which was stable and fast

and which enabled this method to solve arbitrary regions in bypass compression systems composed of fans and any type of high pressure compressors(axial-flow

centrifugal and combined type etc.).Finally this method was applied to an inverse design of a fan/high pressure compressor system

which demonstrated its validity.