Flow characteristics of Axisymmetric Cavity Rear Wall Divergence Angle in a Scramjet Combustor

Abstract

Non-reacting experimental study was performed on a rear wall angled cavity actuated supersonic flow of Mach 1.5 from a convergent divergent nozzle using a blowdown wind tunnel test setup. Ten different model combinations of double angled rear wall cavities is preferred for the study of improvements in the geometrical design of the combustor. Flow field properties of various cavity geometries were analyzed based on the key parameters like, wall static pressures, stagnation pressure loss to the flow and qualitative mixing of flow using momentum flux distribution. The static pressure is found to decrease inside the combustor with a decrease in the secondary dual rear wall angle below 90 degrees whereas value increases at the rear wall OWING to oscillation and recompression of shear layers inside the cavity region. In addition, the decrement in primary rear wall angle, an enhancement in mixing profile and a reduction in stagnation pressure loss are also observed.