Effects of Double-Wedge Aft Angle on Hypersonic Laminar Flows

The aim of this study is to reveal the physics of low-enthalpy Mach 7 flows over double wedges that have varied aft angles and a fixed fore angle of 30 degrees. Comparisons of the obtained numerical schlieren images along with the contours of Q criterion and surface heat fluxes assert that the influence of the vortical structures on the flow becomes more significant in accordance with the value of the aft angle. For the aft angle of theta 2<50 degrees, the three-dimensionality effects are negligible. As the aft angle exceeds 50 degrees, the vortical structures that align in the streamwise direction start to emerge and strengthen over the surfaces of the aft wedge. The characteristic signs of Gortler vortices, distinct striations, also become apparent in the contours of heat flux, density gradient, and pressure on the surfaces of the aft wedge for those cases. The presence of vortical structures enhances heat transfer from the surfaces and together with relieving effects breaks the symmetry down in the flowfield. In general, the vortical structures and relieving effects that take place in the computations diversify the shock structure from those obtained from the two-dimensional computations for the cases with theta 2>50 degrees.