Page 234 - Basic Structured Grid Generation

Unstructured grid generation 223

Fig. 8.45 Initial Delaunay triangulation for an airfoil.

Fig. 8.46 Second stage Delaunay triangulation for an airfoil.

Fig. 8.47 Delaunay triangulation of a geometrically constructed aerofoil, amax = 0.04, armax = 2.0.

any inner boundary or outside any outer boundary of the domain. If so, then the
circumcentre is rejected as a new point. Otherwise it is accepted, added to the list of
data points, and a new triangulation carried out. This procedure is continued until
all the ‘bad’ triangles have been removed.
Calculation of the co-ordinates of the circumcentre is illustrated in Fig. 8.44 for a
general acute-angled triangle. Given the co-ordinates of the vertices, the circum-
radius R may be found by using the combination of eqns (8.1), (8.2), and (8.4).