A Study on Turbulent Heat Transfer Model in Aerodynamic Heating Fields with Dissociation

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For the design of spaceplanes and winged vehicles the accurate estimation of aerodynamic heating load is one of the most important problems. However, those estimations are quite difficult du to the lack of proper turbulent heat flux modeling. The purpose of the present study is to conduct the necessary experiments and computations, which are requested in order to build reliable turbulent heat flux modeling. In the present studies the following studies have been conducted.1) Free-piston high enthalpy shock tunnel has been built. The higher pressure of 250 - 500 bars has been realized at the end of the compression tube. Also characteristics of compression tube and the generation of very strong shock wave have been completed. The top Mach number of the generated shock wave is up to 34.5.(2) It is well known that free-piston high enthalpy shock tunnel has capability to generate high temperature and high pressure air and also the flow duration is quite short. The starting process of wind tu … More nnel is numerically simtulated and the condition for the starting of the nozzle is estimated.(3) The unsteady aerodynamic heating phenomena have been simulated and the effects of high temperature chemical reaction on unsteady aerodynamic heating phenomena have been revealed.(4) The interacting flow fields of shock wave and boundary layer have been simulated with chemically non-equilibrium conditions. The wall catalytic generates quite large difference in heat flux distributions at the wall. Also as the degree of non-equilibrium is increased, the calculated results show that the size of separation, heat flux distribution and pressure distribution can be hanged.(5) For the purpose of the construction of turbulent modeling hypersonic mixing flow fields and boat tail flow structure and high temperature nozzle flow of conventional nozzle have been simulated. Also turbulent modeling with high temperature effects has been considered.(6) Experimental studies on the reduction of aerodynamic heating loads at hypersonic flows have been conducted. Less