Effect of Leading-Edge Bluntness on Shockwave–Boundary-Layer Interaction in a Scramjet Intake

Abstract

An experimental and numerical study was carried out to investigate the effect of leading edge bluntness on the flowfield characteristics of a Mach 6 scramjet inlet. The numerical study was performed using Ansys Fluent 18.0 software. A steady two-dimensional Reynolds-Averaged Navier–Stokes simulation was carried out using k-ε-Re-Normalisation Group model for a sharp edge and leading edge with bluntness of 0.5 and 1 mm (ramp and cowl tip). Significant changes in the flowfield characteristics and parameters were observed for a blunt leading edge compared to the sharp leading edge case. The experimental campaign was carried out in the Mach 6 S1 Hypersonic Ludwieg Tunnel to validate the numerical results, and a good match was observed up to the separation bubble, and deviation in the reattachment is observed. Furthermore, the unsteadiness associated with the shockwave–boundary-layer interaction region inside the isolator was studied for the sharp and blunt leading edge cases. It was observed that changing the leading edge bluntness modifies the flowfield oscillations, separation bubbles, shear layer oscillations, etc.