{"title":"A macro BDM H-div mixed finite element on polygonal and polyhedral meshes","authors":"Xuejun Xu , Xiu Ye , Shangyou Zhang","doi":"10.1016/j.apnum.2024.08.013","DOIUrl":null,"url":null,"abstract":"<div><p>A BDM type of <span><math><mi>H</mi><mo>(</mo><mi>div</mi><mo>)</mo></math></span> mixed finite element is constructed on polygonal and polyhedral meshes. The flux space is the <span><math><mi>H</mi><mo>(</mo><mi>div</mi><mo>)</mo></math></span> subspace of the <em>n</em>-product <span><math><msub><mrow><mi>Π</mi></mrow><mrow><mi>i</mi></mrow></msub><msub><mrow><mi>P</mi></mrow><mrow><mi>k</mi></mrow></msub><msup><mrow><mo>(</mo><msub><mrow><mi>T</mi></mrow><mrow><mi>i</mi></mrow></msub><mo>)</mo></mrow><mrow><mi>d</mi></mrow></msup></math></span> space such that the divergence is a one-piece <span><math><msub><mrow><mi>P</mi></mrow><mrow><mi>k</mi><mo>−</mo><mn>1</mn></mrow></msub></math></span> polynomial on the big polygon or polyhedron <em>T</em>. Here we assume the 2D polygon can be subdivided into triangles by connecting only one vertex with some vertices of the polygon. For the 3D polyhedron we assume it can be subdivided into tetrahedra, with no added vertex on subdividing its face-polygons, and with either no internal edge or one internal edge. Such mixed finite elements can be more economic on quadrilateral and hexahedral meshes, compared with the standard BDM mixed element on triangular and tetrahedral meshes. Numerical tests and comparisons with the triangular and tetrahedral BDM finite elements are provided.</p></div>","PeriodicalId":2,"journal":{"name":"ACS Applied Bio Materials","volume":null,"pages":null},"PeriodicalIF":4.6000,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"ACS Applied Bio Materials","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0168927424002095","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATERIALS SCIENCE, BIOMATERIALS","Score":null,"Total":0}
引用次数: 0
Abstract
A BDM type of mixed finite element is constructed on polygonal and polyhedral meshes. The flux space is the subspace of the n-product space such that the divergence is a one-piece polynomial on the big polygon or polyhedron T. Here we assume the 2D polygon can be subdivided into triangles by connecting only one vertex with some vertices of the polygon. For the 3D polyhedron we assume it can be subdivided into tetrahedra, with no added vertex on subdividing its face-polygons, and with either no internal edge or one internal edge. Such mixed finite elements can be more economic on quadrilateral and hexahedral meshes, compared with the standard BDM mixed element on triangular and tetrahedral meshes. Numerical tests and comparisons with the triangular and tetrahedral BDM finite elements are provided.