Based on the concept of numerical zooming and taking a high bypass ratio turbofan engine as the research carrier

a mixed-dimension computational model to investigate the effect of complex inlet distortion on the characteristics of flow field in aero engines was preliminarily established by integrating a three-dimensional body force model and a two-dimensional multiple segment parallel engine model. The mixed-dimension model was utilized to analyze the characteristics of flow field in the engine under different forms of total pressure distortion

including steady circumferential total pressure distortion and flat baffle total pressure distortion. Results revealed that even if the total circumferential pressure distortion of the square wave at the inlet was simple

there were significant differences in the distortion flow field characteristics at the core and bypass inlet after the action of the fan rotor with high bypass ratio. The combined total pressure/total temperature distortion formed at the core inlet was attenuated under different degrees in the four-stage booster compressor. A certain degree of swirl was induced by the circumferential static pressure gradient near the hub region of the fan rotor inlet under the flat baffle total pressure distortion. Thus

the low pressure area was formed near the hub of the fan rotor outlet.