Experimental Study of Blockerless Cascade Thrust Reverser

Abstract

Modern Aero-engine increasingly requires higher propulsive efficiency, lower weight and less fuel consumption, which motivates researchers all over the world to explore novel technology to achieve these goals. Blockerless cascade thrust reverser is one of such innovative technology, using high pressure secondary flow injecting into fan bypass to fulfill reverse thrust instead of traditional blocker door. The efficiency of thrust reverser is a critical index of the technology, which is a function of aerodynamic and geometric parameters, including fan pressure ratio, secondary injection pressure ratio, injection angle, and injection position. The present study aims to investigate the effects of these parameters on reverse performance through basic demonstration experiments. Firstly, a simple experimental model was designed, which would be conducted on cascade experimental facility. Then, experiments were performed at static conditions, with fixed fluidic injection slot, variable injection angles (30°, 45°, 60°, 90°) at positions of Xj = 38.77mm, 58.77mm, 78.77mm, 98.77mm, 118.77mm, with the scheduled fan pressure ratios (FPR from 1.3 to 1.7) and secondary to ambient pressure ratios (SPR from 2.0 to 6.0). The results indicate that there exits an optimum injection location and injection angle for maximum thrust efficiency, and performance of blockerless cascade thrust reverser varies with diverse fan pressure ratio and secondary injection pressure ratio.