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Hypersonic flows over simple 3-D bodies and a space vehicle are simulated using a real-gas Navier- Stokes code under an equilibrium air assumption. This code is based on 3-D upwind flux splitting scheme with generalized Roe's Riemann solver. The real-gas effect is incorporated using the VEG (Variable Equivalent Gamma) method [1]*. The equivalent gamma and other thermodynamic properties are calculated using empirical curve fits [2]. Numerical simulations are conducted for flow fields around a spherical blunt body, a spherical-nose cylinder, and a cone-cylinder as simple configurations, and HOPE (H-orbiting plane: Japanese spaceplane) as a practical plane configuration. Flow conditons are Mach numbers of 7.72, 15.0 for the blunt bodies, 6.86 for the cone-cylinder, and 15.0 for the HOPE. Computed pressure and density distributions are presented. Results for simple configuration cases are compared with experimental data for the code validation.

Newly developed zonal method using the interface scheme based on the Fortified Navier-Stokes concept is applied to steady and unsteady flow problems. Two computational results are shown as application examples to unsteady flow problems. One problem is a train moving into a tunnel and the other problem is a blast wave propagation. These problem require the accuracy enhancement and the problem adaptability, both of which are important obstacles of the current CFD technology. The computed result indicates that the present method alleviates the difficulty with simple modification of the existing codes. Steady flow problems include supersonic intake flow simulation and three dimensional simulation of the complex body configuration. The results indicate that the present method alleviate the difficulty of the simulation of complex flow configuration.