{"id":433748,"date":"2025-06-10T15:06:02","date_gmt":"2025-06-10T15:06:02","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/help-with-convergence-issues-in-static-structural-analysis\/"},"modified":"2025-06-10T15:06:02","modified_gmt":"2025-06-10T15:06:02","slug":"help-with-convergence-issues-in-static-structural-analysis","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/help-with-convergence-issues-in-static-structural-analysis\/","title":{"rendered":"Help with Convergence Issues in Static Structural Analysis"},"content":{"rendered":"

<p>Hello Everyone,<\/p><p>I’m working on a static structural analysis in Ansys Mechanical (workbench) where beams (bristles) rotate and contact a backplate, but I’m facing persistent issues with the convergence. Here’s a summary of my problem and trials:<\/p><ul dir=”auto”><\/p>\n

  • Geometry<\/strong>: Around 220 beams (consider the bunch of the beams as a rectangular shape) with the near far contact status intially. These beam are rotated with time*8 rotational displacement (8 deg per second) against one fixed plate which 1\/6th of the size of the beams and is working as a stopping plate to these rotated beams. <\/li>\n
  • Material<\/strong>: Structural Steel (Young’s modulus 2e11 Pa).<\/li>\n
  • Load<\/strong>: Rotation applied as 8 deg\/sec <\/li>\n
  • Latest Mesh<\/strong>: Face sizing 0.00007 m (backplate), edge sizing 0.0005 m (beams), body sizing (global) 0.0009 m.<\/li>\n
  • Contact<\/strong>: Frictional (with frictional coeffiecient 0.1) (PurePenalty) with normal stiffness factor 0.012 for beam-beam and beam-backplate pairs. There are around 600 beam – beam contact pairs and 20 beam – backplate contact pairs. <\/li>\n
  • Issue<\/strong>: Total DOF and amount of force increases extensively during the solution process, which could be beyond the limit of the ansys. (Max DOF 8.8746e+6, and Max Force 1.6109e+11 during the solution process). I also tried NCNV,0,1e8 command to elimiate the limit fo the ansys, but it is still not working out. The beams simply messes up, in all the direction like shapeless. <br><br>I am currently applying the following APDL commands: <\/li>\n
  • NCNV,0,1e8  <\/li>\n
  • NEQIT,80<\/li>\n
  • CONTACT, adjust, all, 0.<\/li>\n<\/ul>\n

    <p>I also tried increasing the normal stiffness factor upto 0.1 to 1 to 10 but it still didn’t work out. <\/p><p>Instead of all the 220 beams, when i try to run the simulation only for the nearest beams to the backplate, it converges. But when i try to get the solution for all 220 beams, it doesn’t converge. <br><br>So is there any method, or trick or specific parameter i can use here to find the solution? Anyone has ever worked with this much high amount of the DOF and Forces? If yes, it would be great if you could share some insights on how to get the solution. Even the smallest help would be appreciated.  <\/p><p dir=”auto”>Thanks for your help!<\/p><\/p>\n","protected":false},"template":"","class_list":["post-433748","topic","type-topic","status-publish","hentry","topic-tag-ansysstructuresolveIssue-1","topic-tag-ansysworkbench-ansys-staticstructural","topic-tag-mechanicalworkbench-1","topic-tag-ansyscontact-1","topic-tag-beam","topic-tag-beamelement-1","topic-tag-contact","topic-tag-contact-definition-2","topic-tag-convergence","topic-tag-dof-1","topic-tag-dof-contraints-1","topic-tag-force-convergence-1","topic-tag-nonlinearconvergenceissue-1","topic-tag-structural"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_forum_id":["27791"],"_bbp_topic_id":["433748"],"_bbp_subscription":["476906","240"],"_bbp_author_ip":["129.247.247.239"],"_bbp_last_reply_id":["433842"],"_bbp_last_active_id":["433842"],"_bbp_last_active_time":["2025-06-11 11:42:03"],"_bbp_reply_count":["3"],"_bbp_reply_count_hidden":["0"],"_bbp_voice_count":["2"],"_bbp_engagement":["476906","240"],"_btv_view_count":["312"],"_bbp_topic_status":["unanswered"],"_bbp_notification_enabled":["57984"]},"test":"zeel-joshidlr-de"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/433748","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\/433748\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=433748"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}