Research on aerodynamic influence of contra-rotating propfan slipstream on propfan engine nacelle inlet

In order to investigate the aerodynamic influence of contra-rotating propfan (CRP) slipstream on propfan engine nacelle, numerical simulation research on the CRP/Nacelle integrated configuration was carried out by using sliding mesh unsteady method. The aerodynamic performance of integrated configuration under different working conditions was studied, and compared with nacelle without CRP. Results show that the total pressure recovery coefficient of inlet port increases due to the work done by CRP. However, as the inhale of the wake vortex, the flow structure inside the inlet becomes more complex because of the mixing of wake vortex and wall separation vortex, which leads to a significant increase of distortion index and loss coefficient. Compared with isolated nacelle, the slipstream causes the total pressure recovery coefficient of inlet port increased by 10.2% and 13.4% under cruise condition and takeoff condition, which is accompanied by the intensification of flow loss and non-uniformity inside the inlet, resulting in a significant increase of the total pressure loss coefficient and total pressure distortion index.