Implementation and assessment of modern shock-capturing schemes for hypersonic viscous flows

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2022-8-22

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Şahin, Çağatay

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Spatially second order accurate Finite Volume Method (FVM) is the most preferred method in Computational Fluid Mechanics (CFD) with its acceptable results in short computation times. FVM's accuracy heavily relies on the particular numerical scheme with which the fluxes are evaluated. Despite the maturity of traditional flux schemes today, simulations of a viscous hypersonic ﬂow are still challenging. Since these cases involve strong shock waves and viscous layers with non-linear gradients, appropriate shock capturing is necessary for robust and accurate solutions. In this thesis, modern shock-capturing schemes based on Liou's AUSM and Von Neumann and Richtmyer's artificial viscosity are studied and implemented in an in-house CFD solver. The accuracy and robustness of the implemented methods for viscous hypersonic flow problems are tested with well-known numerical experiments. The comparison of the obtained results with each other and experimental data in the literature is presented. The advantages and disadvantages of schemes among each other are identified.

Subject Keywords

Hypersonics, Shock-capturing, CFD, Finite volume method

URI

https://hdl.handle.net/11511/98778

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

Ç. Şahin, “Implementation and assessment of modern shock-capturing schemes for hypersonic viscous flows,” M.S. - Master of Science, Middle East Technical University, 2022.