The interest in hypersonic flow phenomena has peaked in recent years where numberof experimental and computational work has been carried out. The ComputationalFluid Dynamics (CFD) is fast becoming an invaluable tool to investigatecompressible hypersonic flow phenomena that are extremely complex in nature.Mathematical models employed to describe complex physical phenomenathat take place at hypersonic speeds inherit varying degrees of accuracy and reliability.Therefore, further studies, numerical and experimental, are needed to clarifyand improve these models. Numerical computation is one of the tasks that are vitalin the overall hypersonic flow research effort.This work investigated the applicability and performance of higher resolution methodsto simulate high enthalpy real gas flows. Furthermore, gas-surface interactionand ablation effects are also investigated. In order to achieve the set task, it is imperativethat the numerical code (CNS3D) used is equipped with necessary numericaland physical models to tackle flow behaviour typically unique to hypersonicflow. Therefore, the implementation of mathematical models that describe the realgas phenomena, such as vibrational effects, chemical dissociation, diffusion, andhigh enthalpy effects, has been carried out.The test cases, the HB-2 flare and the double-cone have been considered for thepurposes of verification and validation. The experimental data for heat transferand pressure are compared with numerical predictions to assess the behaviour ofmodified CNS3D overall and each numerical scheme with regards to reconstructionmethods. The overall agreement between the predicted results for both casesand the experimental data is satisfactory. The stagnation point values of pressureand heat flux for HB-2 flare testcase at varying Mach numbers from 5 to 17.8 hasbeen established; these values are expected aid future validation efforts. It wasalso found that very high-order schemes, such as WENO 5th and 9th -order methods,may provide slightly better results for free stream Mach numbers less than 10;however, there are no obvious benefits over second-order methods for Mach numbersgreater than 10. Furthermore, it has been substantiated that increasing orderof accuracy compared to increments in the grid resolution is much more effectiveway of gaining accuracy in the case of real gas flows.
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