**Abstract**

Combined distortions negatively affect the aerodynamic stability of fans, but previous studies have limitations. The 3D CFD method was used to calculate the aerodynamic stability of fans under the total pressure and swirl distortion, total temperature and swirl distortion, and total pressure and total temperature distortion in the work. Rotor 67 was taken as the research object. According to the calculation results, the influences of variable distortion parameters on fan performance under combined distortions were summarized to establish the functional relationship between stability margin losses and distortion parameters.

**Keywords:** combined distortion, stall, aerodynamic performance, fan, aero engine
