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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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References

1. Jameson, A., Schmidt, W. and Turkel, E. Numerical solution of the Euler equations by finite volume methods using Runge-Kutta time stepping schemes, AIAA Paper 81–1259, 1981.Google Scholar
2. Ni, R. I. A multiple grid scheme for solving the Euler equations, AIAA Paper 81–1025, 1981.Google Scholar
3. Lohner, R., Morgan, K. and Zienkiewicz, O. C. The solution of non-linear hyperbolic equation systems by the finite element method, Int J Numer Methods Fluids, 1984, 4, 1043 1063.Google Scholar
4. Miki, K. and Takagi, T. A domain decomposition and overlapping method for the generation of three-dimensional boundary-fitted coordinate systems, J Comput Phys, 1984, 53, 319.Google Scholar
5. Weatherill, N. P. and Forsey, C. R. Grid generation and flow calculations for aircraft geometries, J Aircraft, October 1985, 22, (10), 855860.Google Scholar
6. Bristeau, M. O., Pironneau, O., Glowinski, R., PeriauxJ., P. J., P. and Poirer, G., On the numerical solution of nonlinear problems in fluid dynamics by least squares and finite element methods (II). Application to transonic flow simulations, Proc 3rd Int Conference on Finite Elements in Nonlinear Mechanics, FENOMECH 84, Stuttgart, 1984. Ed. St. Dottsinis, J., North Holland, 363394, 1985.Google Scholar
7. Jameson, A., Baker, T. J. and Weatherill, N. P. Calculation of inviscid transonic flow over a complete aircraft, AIAA Paper 86–0103, 1986.Google Scholar
8. Baker, T. J. Three-dimensional mesh generation by triangulation of arbitrary point sets, Proc of the AIAA 8th CFD Conference, Hawaii, June 1987.Google Scholar
9. Peraire, J., Peiro, J., Formaggio, L., Morgan, K. and Zienkiewicz, O. C. Finite element Euler computations in three dimensions, AIAA Paper 87–0032, 1987.Google Scholar
10. Shaw, J. A., Georgala, J. M. and Weatherill, N. P. The construction of component-adaptive grids for aerodynamic geometries, Proc lnt Conf on Numerical Grid Generation in CFD, Eds Sengupta, , Hauser, , Eiseman, , Thompson, , Pineridge Press, Swansea, 1988.Google Scholar
11. Yoshihara, H. Three-dimensional grid generation for complex configurations, AGARDOGRAPH, 1988.Google Scholar
12. Weatherill, N. P. A method for generating irregular computational grids in multiply connected planar domains. Int J Numer Methods Fluids, 1988, 8, 181197.Google Scholar
13. Rivara, M. C. Algorithm for refining triangular grids suitable for adaptive and multigrid techniques, Int J Numer Methods Eng, 1984, 20, 745756.Google Scholar
14. Steger, J. L. Doughety, F. C. and Benek, J. A. A Chimera grid scheme, In: Advances in Grid Generation, Ed. Ghia, K. N. and Ghia, U., 1983.Google Scholar
15. Weatherill, N. P., Johnston, L. J., Peace, A. J. and Shaw, J. A. A method for the solution of the Reynolds averaged Navier Stokes equations on triangular grids, Proc of the Seventh GAMM Conference on Numerical Methods in Fluid Mechanics, Louvain-la-Neuve, Belgium, September 1987.Google Scholar
16. Hassan, O., Morgan, K. and Peraire, J. An adaptive implicit/explicit finite element scheme for compressible viscous high speed flows, AIAA Paper 89–0363, 1989.Google Scholar
17. Dannenhoffer, J. F. and Baron, J. R. Adaptive procedures for steady state solution of hyperbolic equations, AIAA Paper 84–005, 1984.Google Scholar
18. Nakahashi, N. and Obayashi, S. FDM-FEM zonal approach for viscous flow computations over multiple bodies, AIAA Paper 87–0606, January 1987.Google Scholar
19. Morton, K. W. and Paisley, M. F. On the cell-centre and cell vertex approaches to the steady Euler equations and the use of shock fitting, In Proc 10th Int Conf on Numerical Methods in Fluid Dynamics, Ed. Zhuang, F. G., Zhiu, Y. L., Notes in Physics, 488–493. Springer-Verlag, 264, 488493.Google Scholar