High temperature effects in hypersonic double-wedge flow simulations

Abstract

Numerical simulations of inviscid hypersonic flow over a double-wedge geometry are conducted. High temperature effects are studied using a local thermodynamic equilibrium based model for air. A finite volume based flow solver is developed by combining a weighted essentially non-oscillatory scheme with an approximate Riemann solver. An iterative method to compute shock polars under local thermodynamic equilibrium conditions is suggested. Numerical simulations are conducted to study the effects of changes in geometry, upstream temperature, and upstream velocity. A range for the second wedge angle is identified for which the solution becomes oscillatory. An explanation for this oscillatory nature of the solution is suggested. Existence of a hysteresis phenomenon is also identified. A change in the nature of interaction is observed with changes in upstream temperature and upstream velocity. Local thermodynamic equilibrium based results are compared to those obtained using a calorically perfect gas model for air. Significant differences are observed. Effects of viscosity on the flow field are also studied.