{"id":36418,"date":"2019-07-09T03:23:40","date_gmt":"2019-07-09T03:23:40","guid":{"rendered":"\/forum\/forums\/topic\/convergence-issue-in-non-linear-analysis\/"},"modified":"2019-07-09T03:23:40","modified_gmt":"2019-07-09T03:23:40","slug":"convergence-issue-in-non-linear-analysis","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/convergence-issue-in-non-linear-analysis\/","title":{"rendered":"Convergence issue in Non-linear analysis"},"content":{"rendered":"

Hello,<\/p>\n

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I am trying to simulate a soft pneumatic actuator in Ansys. The material that I am using is Elastomer (Neo-Hookean).<\/p>\n

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The actuator has 4 chambers out of which I am actuating only one i.e. only one chamber has pressure loading as shown in pictres below.<\/p>\n

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This figure shows loading at 9.69s when my solution stops solving. My final load is 0.05 MPa at time 10s. I have given 10 load steps linearly increasing manner and as I was having convergence issues, I increased substeps limits in last step to Min 50-Max 100. I also have added command snippet NEQIT,60 to increase number of equilibrium iterations.<\/p>\n

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This figure shows the pressure variation with time.<\/p>\n

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My mesh looks like:<\/p>\n

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I have refined the mesh near the channel I am applying my pressure into.<\/p>\n

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The problem is: the solution stops at a time of around 9.7 sec and shows a lot of errors like:<\/p>\n

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Attached below are the force and displacement convergence plots and the unconverged solution at time = 9s:<\/p>\n

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My questions are:<\/p>\n

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1) How to make the solution converge?<\/p>\n

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2) If not, can I assume the solution at 9 second as a valid behaviour for a total load of 9\/10*0.05 = 0.045 MPa?<\/p>\n

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Thanks in advance!<\/p>\n","protected":false},"template":"","class_list":["post-36418","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_old_topic_id":["8590"],"_bbp_old_topic_author_name_id":["Anonymous"],"_bbp_old_is_topic_anonymous_id":["false"],"_bbp_old_closed_status_id":["publish"],"_bbp_author_ip":[null],"_bbp_old_sticky_status_id":["normal"],"_bbp_likes_count":["0","0"],"_btv_view_count":["731"],"_bbp_subscription":["241275"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["36418"],"_bbp_forum_id":["27791"],"_bbp_engagement":["897","166615"],"_bbp_voice_count":["2"],"_bbp_reply_count":["2"],"_bbp_last_reply_id":["88987"],"_bbp_last_active_id":["88987"],"_bbp_last_active_time":["2019-07-09 05:30:51"]},"test":"shekhar1234"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/36418","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics"}],"about":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/types\/topic"}],"version-history":[{"count":0,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/36418\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=36418"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}