Variable cycle engine compression part characteristic decoupling method

The invention belongs to the field of aero-engine performance simulation, and relates to a variable cycle engine compression part characteristic decoupling method, which comprises the following steps of: during performance simulation of an engine, firstly decoupling the characteristics of S1 into S1cdfs and S1hpc, then respectively establishing a corresponding relation between the S1cdfs and CDFS basic characteristics, and establishing a corresponding relation between the S1hpc and HPC basic characteristics; on-off angle characteristics of the CDFS and the HPC are respectively calculated by using a basic characteristic corresponding relation and a given angle difference value, each adjustable part is convenient to obtain corresponding characteristics by using a characteristic expression technology, and then a relation between the S1cdfs and the S1hpc, namely a characteristic coupling relation between the CDFS and the HPC, is found through overall performance simulation calculation, so that the characteristic