{"id":162196,"date":"2023-01-25T07:34:34","date_gmt":"2023-01-25T07:34:34","guid":{"rendered":"\/knowledge\/forums\/topic\/how-to-obtain-convergence-when-open-contact-exists\/"},"modified":"2023-07-31T12:36:34","modified_gmt":"2023-07-31T12:36:34","slug":"how-to-obtain-convergence-when-open-contact-exists","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/how-to-obtain-convergence-when-open-contact-exists\/","title":{"rendered":"How to obtain convergence when open contact exists?"},"content":{"rendered":"<p>With a negative offset, you will create a gap between bodies. If a gap exists or if the contact is initially open, there is no stiffness to balance an applied force and the unconstrained body will move infinitely without any chance to close the contact whatever is the time step or the Force amplitude (F=Ku and K=0, so u = inf).  In this case, you have to close the gap with an imposed displacement larger than the gap during a first step. This displacement is deactivated during second step and progressively replaced by the ramped force so that the contact stiffness is non zero at the very beginning of second step.<\/p>\n","protected":false},"template":"","class_list":["post-162196","topic","type-topic","status-publish","hentry","topic-tag-17-1","topic-tag-contact","topic-tag-mechanical","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=\"With a negative offset, you will create a gap between bodies. 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