GENERATION OF ORIENTED 3-DIMENSIONAL DELAUNAY GRIDS SUITABLE FOR THE CONTROL-VOLUME INTEGRATION METHOD

A fully automatic algorithm for three-dimensional mesh generation is presented. The algorithm preserves the robustness and time efficiency of the finite octree technique; replacing octrees by more general 2-4-8-trees, it is capable of generating oriented meshes. In a post-processing step, meshes are transformed in order to satisfy the Delaunay criterion, and so that non-overlapping, closed control volumes can be defined for each mesh point through edge bisectors. The method is shown to be appropriate for modelling semiconductor devices, where the control volume scheme is the method of choice due to the peculiarities of the partial differential equations involved, and where locally refined and oriented meshes are essential to describe the relevant internal physical quantities adequately while keeping the number of mesh points practical.