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Mixed structured-unstructured meshes for aerodynamic flow simulation

Published online by Cambridge University Press:  04 July 2016

N. P. Weatherill*
Affiliation:
Institute for Numerical Methods in EngineeringUniversity College of Swansea

Abstract

Mesh generation is proving to be an important aspect of computational aerodynamics. Over the last few years the topic has received much attention. Methods based on the structured and unstructured philosophies both have their advantages and disadvantages. This paper discusses the possible benefits to be achieved in composite structured-unstructured meshes. An algorithm is described which can solve the Euler equations for inviscid flow on such meshes. Three applications of the composite approach are then described. The first example shows the use of regions of assembled triangles to improve the quality of flow results on a poor quality structured mesh. The second illustrates how geometrically complicated aerodynamic configurations can be treated by utilising local regions of unstructured mesh within a globally structured mesh. Finally, a method of mesh/flow adaptivity is described whereby a structured mesh is enriched in appropriate regions of the domain by the addition of meshes consisting of an assembly of triangles. The results show that distinct benefits can be obtained from this composite approach.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 1990 

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