EFFECTS OF THERMOCHEMICAL AND TRANSPORT MODELS ON THE HIGH-SPEED DOUBLE-CONE FLOWFIELD

The shock wave and boundary layer interaction is common during hypersonic flight, and it is critical for the aerodynamic performance and safety of the flight vehicle. When the enthalpy of the incoming flow is high, its numerical simulation is challenging due to many complex physics and chemistry phenomena whose modelling requires further investigation and study. Hypersonic flow around a double-cone is selected as the test case and the effects of thermochemistry and transport models on the wall pressure and heat transfer rate are studied numerically. The thermochemical models include perfect gas model, thermal non-equilibrium with frozen or non-equilibrium chemistry, and thermal equilibrium with non-equilibrium chemistry. The transport models include the widely used Wilke/Blottner/Eucken model, and the more physically complicated Gupta/SCEBD model. Moreover, the influence of wall catalysis is also considered. The six experimental test runs, covering from low to high enthalpy inflow conditions, are simulated. The computed results show that the computed wall pressure and heat flux agree with the experiments. Under the low enthalpy condition, the distribution of the molecular internal energy has a big impact on the results, and the two transport models produce similar results. Under the high enthalpy condition, the chemical reaction and wall catalysis have a significant influence. Comparison of the results with the different transport models shows much larger difference for higher freestream enthalpy.