Direct Numerical Simulation of Roughness Induced Hypersonic Boundary Layer Transition on a Seven Degree Half-Angle Cone

摘要

DNS CFD calculations were performed on a 30 slice of 7 half-angle cones with increasing nose radii at Mach 10 while simulating a distributed roughness pattern on the cone surface. These DNS computations were designed to determine if the transition behavior observed by the AEDC Tunnel 9 was induced via distributed surface roughness. Blunt nose experiments indicated that as the nose radius continued to increase, the transition location was no longer second mode dominated and the transition location failed to continue to move downstream. The DNS results employed the grids which simulated distributed roughness. The distributed surface roughness was not sufficient to cause transitional flow.