{"title":"论二维 P4+ 三角形和三维 P6+ 四面体无发散有限元的收敛性","authors":"Shangyou Zhang","doi":"10.1002/num.23088","DOIUrl":null,"url":null,"abstract":"We show that the discrete velocity solution converges at the optimal order when solving the steady state Stokes equations by the <math altimg=\"urn:x-wiley:num:media:num23088:num23088-math-0003\" display=\"inline\" location=\"graphic/num23088-math-0003.png\" overflow=\"scroll\">\n<semantics>\n<mrow>\n<msub>\n<mrow>\n<mi>P</mi>\n</mrow>\n<mrow>\n<mi>k</mi>\n</mrow>\n</msub>\n</mrow>\n$$ {P}_k $$</annotation>\n</semantics></math>-<math altimg=\"urn:x-wiley:num:media:num23088:num23088-math-0004\" display=\"inline\" location=\"graphic/num23088-math-0004.png\" overflow=\"scroll\">\n<semantics>\n<mrow>\n<msubsup>\n<mrow>\n<mi>P</mi>\n</mrow>\n<mrow>\n<mi>k</mi>\n<mo form=\"prefix\">−</mo>\n<mn>1</mn>\n</mrow>\n<mrow>\n<mtext>disc</mtext>\n</mrow>\n</msubsup>\n</mrow>\n$$ {P}_{k-1}^{\\mathrm{disc}} $$</annotation>\n</semantics></math> mixed finite element method for <math altimg=\"urn:x-wiley:num:media:num23088:num23088-math-0005\" display=\"inline\" location=\"graphic/num23088-math-0005.png\" overflow=\"scroll\">\n<semantics>\n<mrow>\n<mi>k</mi>\n<mo>≥</mo>\n<mn>4</mn>\n</mrow>\n$$ k\\ge 4 $$</annotation>\n</semantics></math> on 2D triangular grids or <math altimg=\"urn:x-wiley:num:media:num23088:num23088-math-0006\" display=\"inline\" location=\"graphic/num23088-math-0006.png\" overflow=\"scroll\">\n<semantics>\n<mrow>\n<mi>k</mi>\n<mo>≥</mo>\n<mn>6</mn>\n</mrow>\n$$ k\\ge 6 $$</annotation>\n</semantics></math> on tetrahedral grids, even in the case the inf-sup condition fails. By a simple <math altimg=\"urn:x-wiley:num:media:num23088:num23088-math-0007\" display=\"inline\" location=\"graphic/num23088-math-0007.png\" overflow=\"scroll\">\n<semantics>\n<mrow>\n<msup>\n<mrow>\n<mi>L</mi>\n</mrow>\n<mrow>\n<mn>2</mn>\n</mrow>\n</msup>\n</mrow>\n$$ {L}^2 $$</annotation>\n</semantics></math>-projection of the discrete <math altimg=\"urn:x-wiley:num:media:num23088:num23088-math-0008\" display=\"inline\" location=\"graphic/num23088-math-0008.png\" overflow=\"scroll\">\n<semantics>\n<mrow>\n<msub>\n<mrow>\n<mi>P</mi>\n</mrow>\n<mrow>\n<mi>k</mi>\n<mo form=\"prefix\">−</mo>\n<mn>1</mn>\n</mrow>\n</msub>\n</mrow>\n$$ {P}_{k-1} $$</annotation>\n</semantics></math> pressure to the space of continuous <math altimg=\"urn:x-wiley:num:media:num23088:num23088-math-0009\" display=\"inline\" location=\"graphic/num23088-math-0009.png\" overflow=\"scroll\">\n<semantics>\n<mrow>\n<msub>\n<mrow>\n<mi>P</mi>\n</mrow>\n<mrow>\n<mi>k</mi>\n<mo form=\"prefix\">−</mo>\n<mn>1</mn>\n</mrow>\n</msub>\n</mrow>\n$$ {P}_{k-1} $$</annotation>\n</semantics></math> polynomials, we show this post-processed pressure solution also converges at the optimal order. Both 2D and 3D numerical tests are presented, verifying the theory.","PeriodicalId":2,"journal":{"name":"ACS Applied Bio Materials","volume":null,"pages":null},"PeriodicalIF":4.6000,"publicationDate":"2024-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"On the convergence of 2D P4+ triangular and 3D P6+ tetrahedral divergence-free finite elements\",\"authors\":\"Shangyou Zhang\",\"doi\":\"10.1002/num.23088\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"We show that the discrete velocity solution converges at the optimal order when solving the steady state Stokes equations by the <math altimg=\\\"urn:x-wiley:num:media:num23088:num23088-math-0003\\\" display=\\\"inline\\\" location=\\\"graphic/num23088-math-0003.png\\\" overflow=\\\"scroll\\\">\\n<semantics>\\n<mrow>\\n<msub>\\n<mrow>\\n<mi>P</mi>\\n</mrow>\\n<mrow>\\n<mi>k</mi>\\n</mrow>\\n</msub>\\n</mrow>\\n$$ {P}_k $$</annotation>\\n</semantics></math>-<math altimg=\\\"urn:x-wiley:num:media:num23088:num23088-math-0004\\\" display=\\\"inline\\\" location=\\\"graphic/num23088-math-0004.png\\\" overflow=\\\"scroll\\\">\\n<semantics>\\n<mrow>\\n<msubsup>\\n<mrow>\\n<mi>P</mi>\\n</mrow>\\n<mrow>\\n<mi>k</mi>\\n<mo form=\\\"prefix\\\">−</mo>\\n<mn>1</mn>\\n</mrow>\\n<mrow>\\n<mtext>disc</mtext>\\n</mrow>\\n</msubsup>\\n</mrow>\\n$$ {P}_{k-1}^{\\\\mathrm{disc}} $$</annotation>\\n</semantics></math> mixed finite element method for <math altimg=\\\"urn:x-wiley:num:media:num23088:num23088-math-0005\\\" display=\\\"inline\\\" location=\\\"graphic/num23088-math-0005.png\\\" overflow=\\\"scroll\\\">\\n<semantics>\\n<mrow>\\n<mi>k</mi>\\n<mo>≥</mo>\\n<mn>4</mn>\\n</mrow>\\n$$ k\\\\ge 4 $$</annotation>\\n</semantics></math> on 2D triangular grids or <math altimg=\\\"urn:x-wiley:num:media:num23088:num23088-math-0006\\\" display=\\\"inline\\\" location=\\\"graphic/num23088-math-0006.png\\\" overflow=\\\"scroll\\\">\\n<semantics>\\n<mrow>\\n<mi>k</mi>\\n<mo>≥</mo>\\n<mn>6</mn>\\n</mrow>\\n$$ k\\\\ge 6 $$</annotation>\\n</semantics></math> on tetrahedral grids, even in the case the inf-sup condition fails. By a simple <math altimg=\\\"urn:x-wiley:num:media:num23088:num23088-math-0007\\\" display=\\\"inline\\\" location=\\\"graphic/num23088-math-0007.png\\\" overflow=\\\"scroll\\\">\\n<semantics>\\n<mrow>\\n<msup>\\n<mrow>\\n<mi>L</mi>\\n</mrow>\\n<mrow>\\n<mn>2</mn>\\n</mrow>\\n</msup>\\n</mrow>\\n$$ {L}^2 $$</annotation>\\n</semantics></math>-projection of the discrete <math altimg=\\\"urn:x-wiley:num:media:num23088:num23088-math-0008\\\" display=\\\"inline\\\" location=\\\"graphic/num23088-math-0008.png\\\" overflow=\\\"scroll\\\">\\n<semantics>\\n<mrow>\\n<msub>\\n<mrow>\\n<mi>P</mi>\\n</mrow>\\n<mrow>\\n<mi>k</mi>\\n<mo form=\\\"prefix\\\">−</mo>\\n<mn>1</mn>\\n</mrow>\\n</msub>\\n</mrow>\\n$$ {P}_{k-1} $$</annotation>\\n</semantics></math> pressure to the space of continuous <math altimg=\\\"urn:x-wiley:num:media:num23088:num23088-math-0009\\\" display=\\\"inline\\\" location=\\\"graphic/num23088-math-0009.png\\\" overflow=\\\"scroll\\\">\\n<semantics>\\n<mrow>\\n<msub>\\n<mrow>\\n<mi>P</mi>\\n</mrow>\\n<mrow>\\n<mi>k</mi>\\n<mo form=\\\"prefix\\\">−</mo>\\n<mn>1</mn>\\n</mrow>\\n</msub>\\n</mrow>\\n$$ {P}_{k-1} $$</annotation>\\n</semantics></math> polynomials, we show this post-processed pressure solution also converges at the optimal order. Both 2D and 3D numerical tests are presented, verifying the theory.\",\"PeriodicalId\":2,\"journal\":{\"name\":\"ACS Applied Bio Materials\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":4.6000,\"publicationDate\":\"2024-01-21\",\"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://doi.org/10.1002/num.23088\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"MATERIALS SCIENCE, BIOMATERIALS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"ACS Applied Bio Materials","FirstCategoryId":"100","ListUrlMain":"https://doi.org/10.1002/num.23088","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATERIALS SCIENCE, BIOMATERIALS","Score":null,"Total":0}
On the convergence of 2D P4+ triangular and 3D P6+ tetrahedral divergence-free finite elements
We show that the discrete velocity solution converges at the optimal order when solving the steady state Stokes equations by the - mixed finite element method for on 2D triangular grids or on tetrahedral grids, even in the case the inf-sup condition fails. By a simple -projection of the discrete pressure to the space of continuous polynomials, we show this post-processed pressure solution also converges at the optimal order. Both 2D and 3D numerical tests are presented, verifying the theory.