四面体单元网格加密过程中的曲面逼近算法及程序实现

An Approach Conicoid Boundary Algorithm and its Related Procedure for Tetrahedral Mesh during Refined Process

本文介绍了一种在四面体单元网格的加密过程中实现曲面逼近的算法。单元加密采用了最长边加密算法,曲面逼近实现了对二次曲面的逼近功能。当加密点所在边是边界面上的边时,将该点挪到对应的边界面上。挪动时根据该边所参与的两个边界三角形面的法向方向来确定加密点的挪动方向,再结合二次曲面方程来计算出挪动后点的新坐标。算例表明,对于由二次曲面边界围成的物体,这种算法能够有效地实现网格加密过程中的曲面边界逼近功能。

An algorithm for tetrahedron mesh that can approach to the conicoid boundary during the refined process was presented. The longest-edge refinement algorithm was used to refine the mesh. When a new refined node is on a boundary side , the node should be moved to the conicoid-boundary. The moving direction was defined considering the normal directions of two boundary triangle faces . The equation of the conicoid was used to calculate the new coordinates of the node after moving. Examples show that the algorithm is effective to implement the approach to the conicoid-boundary during refined process.