NURBS based scheme for automatic quadrilateral mesh generation for FE and BEM analysis

In this paper, a Non Uniform Rational B-Spline (NURBS) based approach is proposed to generate structured quadrilateral meshes over three dimensional surfaces. The surfaces to be meshed are defined by NURBS. The surfaces can also have a hole of arbitrary shape. Initially an adaptive subdivision scheme applied to split the surface in parametric domain to match the boundary nodes, and then mesh generation process reduces to the formation of nodes and elements in parametric domain. In order to do that, special care is taken to maintain the continuity of the splitted surfaces. The primary objective of this paper is to recognize the neighbouring surfaces and split automatically to match the boundary points. None of the presently available CAD software has this type of feature. The proposed scheme is applied initially with simply connected surface, and then it is applied for more complicated structures. Finally the proposed method is applied to a part of a ship shaped body consisting with planar and curved surfaces to demonstrate the effectiveness of the proposed algorithm.