Numerical analysis of rotating ramps in a scramjet engine

Abstract

Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.A concept of mixing enhancement forced by rotating ramps has been presented, which based on the design of stationary ramps and Rim-Rotor Rotary Ramjet Engine. The rotating ramps could generate large scale vortex and rotary moving shock waves, which may increase the fuel mixing rate and spread distance in transverse-direction. The commercial software Fluent has been conducted to study the effect of different velocity of ramps rotating on flowfield characteristics. The results show that rotating ramps increase the periodic oscillation of cavity shear layer and induce large streamwise vortices in cavity. When the ramps rotate at a speed of 54.3krpm, the peak value of x-vortex magnitude is nearly four times as the stationary ramps, however, the coefficient of total pressure recovery in the rotating ramps case is nearly 10% less than that in the stationary ramps case. This study provides a new method for mixing enhancement under supersonic airflow condition.