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NASA NTRS · 20220008150

Adaptive mesh refinement and turbulence modeling

Michael E. Olsen
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Abstract

Adaptive mesh refinement is shown to be essential in turbulence modeling. Adaptive Mesh Refinement (AMR) is a more computationally efficient means to obtain a discrete approximation to a continuous boundary value problem of a specified accuracy than classic isotropic grid refinement. Previous application of this methodology in the assessment of turbulence models suggested that the field variable solution on the interior of the domain was more sensitive to grid refinement than would be suggested by the sensitivity to grid refinement of surface quantities. Revisiting challenging high speed flow field revealed that issues believed to be fundamental turbulence model issues appear to be related to an under-resolved boundary layer edge – a flow detail previously considered unimportant.

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HypersonicsAdaptive Mesh RefinementTurbulence modelingComputational Fluid Dynamics

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Michael E. Olsen. Adaptive mesh refinement and turbulence modeling. https://ntrs.nasa.gov/citations/20220008150

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