Experimental Investigations on Aft Ramp Cavities with Fore Wall Modifications in Scramjet Combustors

The present work focuses on the characteristics of cavity flow with fore wall modifications in a blow down type non-reacting supersonic flow facility. The facility consists of a supersonic nozzle which provides a flow Mach number of 1.44, a stagnation pressure of 0.38 MPa and a total temperature of 300 K. A supersonic combustor of circular cross section, 26 mm in diameter and 130 mm in length, was integrated with the nozzle. Axisymmetric aft ramp cavities of varying depth and ramp angles were placed inside the combustor at a distance of 30 mm from the inlet. A constant fillet dimension of 3 mm at the fore wall of the cavity was used for the investigation. Fore wall fillet cavities provide more fluid entrainment than that absence of fore wall modification with marginal increase in stagnation pressure loss.