Unstructured vs Structured Grids

The finite volume approach is used to solve the convection equation numerically. There are two methods of discretizing the domain: the structured grid system and the unstructured grid system. The main advantage of an unstructured mesh over the structured mesh is in the handling of complex geometrical domains. Figure 1a shows the structured grid system about a cylinder. Each grid point can be identified by its and indices, and all neighboring points are easily located. Figure 1b shows the unstructured grid system. In contrast to the structured grid system, the mesh points in an unstructured grid system are not organized in an orderly manner. The main difference between the structured grid system and the unstructured grid system is in the identification of the points forming the computational cell and its neighbors.

Figure 1a: Structured mesh

Figure 1b: Unstructured mesh[2]