Study on technique of finite-difference grid subdivision in three dimensional pre-processing system

According to the computational grids of 3D fluid-elastoplastic computational procedures MMIC3D are orthogonal hexahedral grids, an automatic software of grids subdivision MESH-3D is developed, which can realize complicated solid modeling, and subdivide solid models into finite-difference grids. Two kinds of modeling methods, CSG and STL model, are used in MESH-3D. MESH-3D subdivide CSG solid models into finite-difference grids through calculating contour lines layer by layer, subdivides STL models into finite-difference grids through using Edge-based integral slice algorithm and refer to the scanning line filling technique of computational graphics. Finally, the reasons why MESH-3D subdivides STL models into finite-difference grids faster than subdivides CSG solid models are analyzed. This process is conductive to other calculations and post-processing display.