{"id":158111,"date":"2022-06-06T09:58:41","date_gmt":"2022-06-06T09:58:41","guid":{"rendered":"\/knowledge\/forums\/topic\/why-do-some-surface-to-surface-bonded-mpc-contact-have-an-unexpected-initial-status-for-my-mixed-solid-shell-model\/"},"modified":"2022-06-06T09:58:41","modified_gmt":"2022-06-06T09:58:41","slug":"why-do-some-surface-to-surface-bonded-mpc-contact-have-an-unexpected-initial-status-for-my-mixed-solid-shell-model","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/why-do-some-surface-to-surface-bonded-mpc-contact-have-an-unexpected-initial-status-for-my-mixed-solid-shell-model\/","title":{"rendered":"Why do some surface-to-surface bonded MPC contact have an unexpected initial status for my mixed solid &#038; shell model?"},"content":{"rendered":"<p>The problem is due to overconstraints and equation elimination.   Special care is required in the use of MPC for mixed assembly solid\/shell\/solid.  By default, users are used to applying contact only on shells and target on solids, but unfortunately in the particular case of contact on both sides of the shell (each contact belonging to one pair), Mechanical will detect overconstraint status and will deactivate one the contact regions.  This may lead to rigid body motion. To avoid this, either alternate contact and shell on both sides of the shell (if MPC contact must be kept) or in case of contact are defined on both shell sides, use penalty method or augmented lagrange instead.<\/p>\n","protected":false},"template":"","class_list":["post-158111","topic","type-topic","status-publish","hentry","topic-tag-bonded-contact","topic-tag-initial-status","topic-tag-mpc"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 4.9.10 - aioseo.com -->\n\t<meta name=\"description\" content=\"The problem is due to overconstraints and equation elimination. Special care is required in the use of MPC for mixed assembly solid\/shell\/solid. By default, users are used to applying contact only on shells and target on solids, but unfortunately in the particular case of contact on both sides of the shell (each contact belonging to\" \/>\n\t<meta name=\"robots\" content=\"max-image-preview:large\" \/>\n\t<link rel=\"canonical\" href=\"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/why-do-some-surface-to-surface-bonded-mpc-contact-have-an-unexpected-initial-status-for-my-mixed-solid-shell-model\/\" \/>\n\t<meta name=\"generator\" content=\"All in One SEO (AIOSEO) 4.9.10\" \/>\n\t\t<meta property=\"og:locale\" content=\"en_US\" \/>\n\t\t<meta property=\"og:site_name\" content=\"Ansys Knowledge | Ansys Innovation Space\" \/>\n\t\t<meta property=\"og:type\" content=\"article\" \/>\n\t\t<meta property=\"og:title\" content=\"Why do some surface-to-surface bonded MPC contact have an unexpected initial status for my mixed solid &amp; shell model? | Ansys Knowledge\" \/>\n\t\t<meta property=\"og:description\" content=\"The problem is due to overconstraints and equation elimination. Special care is required in the use of MPC for mixed assembly solid\/shell\/solid. By default, users are used to applying contact only on shells and target on solids, but unfortunately in the particular case of contact on both sides of the shell (each contact belonging to\" \/>\n\t\t<meta property=\"og:url\" content=\"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/why-do-some-surface-to-surface-bonded-mpc-contact-have-an-unexpected-initial-status-for-my-mixed-solid-shell-model\/\" \/>\n\t\t<meta property=\"article:published_time\" content=\"2022-06-06T09:58:41+00:00\" \/>\n\t\t<meta property=\"article:modified_time\" content=\"2022-06-06T09:58:41+00:00\" \/>\n\t\t<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n\t\t<meta name=\"twitter:title\" content=\"Why do some surface-to-surface bonded MPC contact have an unexpected initial status for my mixed solid &amp; shell model? | Ansys Knowledge\" \/>\n\t\t<meta name=\"twitter:description\" content=\"The problem is due to overconstraints and equation elimination. Special care is required in the use of MPC for mixed assembly solid\/shell\/solid. 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