Grid-Based Local Refinement Algorithm of Three-Dimensional Hexahedral Meshes

The accuracy and efficiency of finite element numerical analysis have close relationship with the mesh quality and density distribution.In order to ensure the hexahedral mesh transition gradually and conformably,a set of 8-refinement based density control templates is proposed newly.The corresponding date structure and template application techniques are also given.Adjustment rules are built for conversion of every element in the refinement field to a corresponding 8-refinement based density control template.For the regions to be refined,the refinement elements are firstly supplemented.Secondly,the refinement fields are adjusted according to the node refinement attribute.Thirdly,the elements to be refined are classified into all refinement element,face refinement element,edge refinement element and transition refinement element according to the element refinement attribute and then refined with the corresponding template respectively.Thus the local refinement of all-hexahedral meshes can be realized.The examples show that the local refinement algorithm can guarantee the gradual and conformal transition from dense meshes to sparse meshes by using the 8-refinement based density control templates.The generated mesh can satisfy the requirement of finite element numerical analysis.