{"id":167069,"date":"2023-04-05T14:32:48","date_gmt":"2023-04-05T14:32:48","guid":{"rendered":"\/knowledge\/forums\/topic\/the-4-noded-linear-tetrahedral-element-is-generally-too-stiff-to-provide-good-response-accuracy-does-the-solid285-element-also-suffer-this-same-problem\/"},"modified":"2023-07-31T12:32:24","modified_gmt":"2023-07-31T12:32:24","slug":"the-4-noded-linear-tetrahedral-element-is-generally-too-stiff-to-provide-good-response-accuracy-does-the-solid285-element-also-suffer-this-same-problem","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/the-4-noded-linear-tetrahedral-element-is-generally-too-stiff-to-provide-good-response-accuracy-does-the-solid285-element-also-suffer-this-same-problem\/","title":{"rendered":"The 4-noded linear tetrahedral element is generally too stiff to provide good response accuracy. Does the Solid285 element also suffer this same problem?"},"content":{"rendered":"<p>The 4-noded linear tetrahedral elements that uses pure displacement formulation generally suffer from volumetric locking. This is due to inaccurate calculation of volumetric strains that results in an overly stiff response. In SOLID285 elements, u-P formulation is used which introduces hydrostatic pressure as an additional degree of freedom. As a result, the accuracy of the volumetric calculations are improved significantly, so the response of SOLID285 elements is very accurate.  However, The element may not offer sufficient accuracy for bending-dominant problems, especially if the mesh is not fine enough. Therefore, it is not recommended in bending dominated problems.<\/p>\n","protected":false},"template":"","class_list":["post-167069","topic","type-topic","status-publish","hentry","topic-tag-18-2","topic-tag-mechanical","topic-tag-static","topic-tag-structural-and-thermal","topic-tag-structural-mechanics"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 4.9.10 - aioseo.com -->\n\t<meta name=\"description\" content=\"The 4-noded linear tetrahedral elements that uses pure displacement formulation generally suffer from volumetric locking. This is due to inaccurate calculation of volumetric strains that results in an overly stiff response. In SOLID285 elements, u-P formulation is used which introduces hydrostatic pressure as an additional degree of freedom. 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Does the Solid285 element also suffer this same problem? | Ansys Knowledge","og:description":"The 4-noded linear tetrahedral elements that uses pure displacement formulation generally suffer from volumetric locking. This is due to inaccurate calculation of volumetric strains that results in an overly stiff response. In SOLID285 elements, u-P formulation is used which introduces hydrostatic pressure as an additional degree of freedom. As a result, the accuracy of the","og:url":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/the-4-noded-linear-tetrahedral-element-is-generally-too-stiff-to-provide-good-response-accuracy-does-the-solid285-element-also-suffer-this-same-problem\/","article:published_time":"2023-04-05T14:32:48+00:00","article:modified_time":"2023-07-31T12:32:24+00:00","twitter:card":"summary_large_image","twitter:title":"The 4-noded linear tetrahedral element is generally too stiff to provide good response accuracy. 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