Applied Computational Fluid Dynamics Techniques: An Introduction Based on Finite Element Methods, 2nd Edition

3 GRID GENERATION

Numerical methods based on the spatial subdivision of a domain into polyhedra or elements immediately imply the need to generate a mesh. With the availability of more versatile field solvers and powerful computers, analysts attempted the simulation of ever increasing geometrical and physical complexity. At some point (probably around 1985), the main bottleneck in the analysis process became the grid generation itself. The late 1980s and 1990s have seen a considerable amount of effort devoted to automatic grid generation, as evidenced by the many books (e.g. Carey (1993, 1997), George (1991a), George and Borouchaki (1998), Frey (2000)) and conferences devoted to the subject (e.g. the bi-annual International Conference on Numerical Grid Generation in Computational Fluid Dynamics and Related Fields (Sengupta et al. (1988), Arcilla et al. (1991), Weatherill et al. (1993b))) and the yearly Meshing Roundtable organized by Sandia Laboratories (1992–present) resulting in a number of powerful and, by now, mature techniques.

Mesh types are as varied as the numerical methodologies they support, and can be classified according to:

• conformality;
• surface or body alignment;
• topology; and
• element type.

The different mesh types have been sketched in Figure 3.1.

Conformality denotes the continuity of neighbouring elements across edges or faces. Conformal meshes are characterized by a perfect match of edges and faces between neighbouring elements. Non-conforming meshes exhibit ...