Long-term behavior of high enthalpy reacting flows over double wedges at Mach 7

The present study focuses on unsteady shock interaction mechanisms in high enthalpy reacting Mach 7 flows of air over double wedges with fixed fore angle of 30 degrees and aft angles of 45 degrees,50 degrees,55 degrees, and 60 degrees. For this purpose, a pre-validated Navier-Stokes finite volume solver, hyperReactingFoam that combines two solvers of OpenFOAM, density-based compressible solver, rhoCentralFoam, and reactingFoam is used. The solver has capabilities of modeling chemical reactions in both thermal equilibrium and non-equilibrium hypersonic flows besides shock interactions. Although there are considerable amount of studies in the literature that focus on short and long-term behaviors of shock interaction mechanisms over double wedges, there is still a need to reveal long-term effects of high enthalpy reacting flows on flow physics and shock interaction mechanisms. The present study has been designed and conducted to address these needs. Our computational results reveal that high enthalpy reacting flows over double wedges differ from those with low enthalpy in terms of aft angle threshold value for periodicity, thickness and length of the separation zone over the compression corner, and the strength of the vortex cores that form over the compression corner. In addition to those, the surface heat flux values can reach 60-fold of the values observed in the low enthalpy flows. Our results also show that reaction zone covers wider area as the aft angle is increased but in contrast to low enthalpy flows this does not affect the period of the flow.