Overview

In Chapter 1, geometric modeling is shown to be one of the essential steps in the numerical simulation process as illustrated in Fig. 1.1. The second box in the process, geometric modeling, is composed of three parts; geometry creation, geometric healing, and mesh enhancement boundary conditions, as shown in Fig. 2.1.

Figure 2.1: The Geometric Modeling step in the numerical simulation process contains at least the three parts: (1) CAD creation of or other source for domain geometry, (2) healing of the geometry to fix overlaps, gaps, etc., and (3) definition of boundary conditions for the mesh generation and enhancement process.

The first contribution to Geometric Modeling is geometry creation. The geometry may be trivial, as in a box or circular cylindrical domain. Alternatively, it may be extremely complex requiring engineering analysis using a computer aided design (CAD) software package. Geometry may also be created from discrete coordinate locations in physical space or from triangulations of higher-level geometric objects. In some instances, geometry may be formed from the Boolean compounding of simple geometric shapes. Independent of the particular creation process, geometry must be expressed in a form that supports the operations and evaluations required by the Mesh Generation process.

The second part of Geometric Modeling concerns the verification of geometric forms provided by the creation step to insure there are no unexpected gaps and/or overlaps in the geometry. Verification is aimed at assessing the geometric data to be used for the Mesh Generation process. The evaluation and repair...