Effect of Meridional Characteristic Angle on Aerodynamic Performance of Ram-Rotor

A kind of meridional concept which has a shape of contraction-expansion(Con-Exp) was applied to the ram-rotor in the paper, and detailed numerical simulation to understand the impact of meridional shape and geometric characteristic angle on the aerodynamic behavior of ram-rotors has been undertaken. Compared to baseline, there was a positive effect in intensifying shock train and suppressing low momentum fluid in Con-Exp scheme, and the pressure ratio and efficiency of Con-Exp scheme increased by 2.075% and 3.160%, respectively. When the contracting angle was increasing, supersonic flow at and after throat region accelerated remarkably, and the static pressure rise was decreased gradually. The terminating shock train was transformed to terminating shock, and the efficiency of ram-rotor was unfavorable to improve due to low throttle extent. As expanding angle rose, the terminating shock moved forward and turned to shock train gradually. The pressure rise capacity and throttling ability of ram-rotor were raised. More low momentum fluid was accumulated near the middle and upper flow-path, yielding greater flow loss at large expanding angle.