


{"id":390449,"date":"2024-10-18T16:19:33","date_gmt":"2024-10-18T16:19:33","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/generation-of-constraint-equation-issues\/"},"modified":"2024-10-21T13:13:17","modified_gmt":"2024-10-21T13:13:17","slug":"generation-of-constraint-equation-issues","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/generation-of-constraint-equation-issues\/","title":{"rendered":"Generation of constraint equation issues"},"content":{"rendered":"<p>&lt;p&gt;&lt;p&gt;Hello,&nbsp;&lt;\/p&gt;&lt;p&gt;My name is ReddyRamu, I have a problem regarding substructure generation. I&acute;m a student writing a master&#8217;s thesis on a journal (EHD) bearings using AVL EXCITE M. For this I need to prepare a substructure file which could be later imported to AVL EXCITE. I could generate an EXB file for bearing wall without any issues. But, for bearing pin\/&lt;span style=&#8221;font-size: 14pt;&#8221;&gt;journal there is an issue. I could generate the EXB file but with some warnings. I think this is because I defined the interface points of the bearing pin wi&lt;\/span&gt;&lt;span style=&#8221;font-size: 14pt;&#8221;&gt;th MASS21 elements with negligible inertias as recommended.&nbsp;&lt;\/span&gt;&lt;\/p&gt;&lt;p&gt;After meshing I had to define some interface points (master nodes) in the center of the journal. These interface nodes should be defined with MASS21 elements with KEYOPT(3)=0, negligible mass, and rotational inertias. <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/10\/18-10-2024-1729267922-Screenshot (711).png\" alt=\"\" width=\"496\" height=\"279\" \/>&lt;\/p&gt;&lt;p&gt;Later I need to generate constraint equation CE\/CERIG to connect these interface nodes to the surrounding slave nodes.&lt;span style=&#8221;font-size: 14pt;&#8221;&gt;&nbsp;I did all this in Me&lt;\/span&gt;&lt;span style=&#8221;font-size: 14pt;&#8221;&gt;chanicl APDL&nbsp;&lt;\/span&gt;<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/10\/18-10-2024-1729268263-Screenshot 2024-10-03 111745.png\" alt=\"\" width=\"643\" height=\"247\" \/><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/10\/18-10-2024-1729268308-Screenshot 2024-09-19 181913.png\" alt=\"\" width=\"651\" height=\"251\" \/>&lt;\/p&gt;&lt;p&gt;&lt;span style=&#8221;font-size: 14pt;&#8221;&gt;and later imported it to the workbench to generate an&nbsp;&lt;\/span&gt;&lt;span style=&#8221;font-size: 14pt;&#8221;&gt;EXB file using the APDL command.&nbsp; but When I imported the CDB file (APDL) to Workbench, there was an&lt;\/span&gt;&lt;span style=&#8221;font-size: 14pt;&#8221;&gt;&nbsp;undefined component <code>point mass<\/code>.<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/10\/18-10-2024-1729268074-Screenshot (712).png\" alt=\"\" width=\"506\" height=\"285\" \/> &lt;\/span&gt;&lt;\/p&gt;&lt;p&gt;&lt;span style=&#8221;font-size: 14pt;&#8221;&gt;I wasn&acute;t sure how to fix it so I just suppressed it and ran the script. It created an EXB file but, when I imp&lt;\/span&gt;&lt;span style=&#8221;font-size: 14pt;&#8221;&gt;orted the EXB file in EXCITE, I was missing all the rotational DOFs at interface points. as you can see all this in the below pictures.&lt;\/span&gt;&lt;\/p&gt;&lt;p&gt;&lt;span style=&#8221;font-size: 14pt;&#8221;&gt;<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/10\/18-10-2024-1729268148-Screenshot 2024-10-07 172126.png\" alt=\"\" width=\"726\" height=\"561\" \/>&lt;\/span&gt;&lt;\/p&gt;&lt;p&gt;If possible could anyone help me to define the CEs between center and slave nodes correctly?&lt;\/p&gt;&lt;p&gt;&nbsp;&lt;\/p&gt;&lt;p&gt;Thank you!&lt;\/p&gt;&lt;p&gt;Reddyramu Gundlooru&lt;\/p&gt;&lt;div&gt;&nbsp;&lt;\/div&gt;&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-390449","topic","type-topic","status-publish","hentry","topic-tag-dof-contraints-1","topic-tag-substructuring-2"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["465704","20905"],"_bbp_author_ip":["2a02:2455:722:9300:e4ee:a8e2:af16:abe1"],"_btv_view_count":["411"],"_bbp_topic_status":["unanswered"],"_edit_last":["9935"],"_bbp_revision_log":["a:1:{i:390638;a:2:{s:6:\"author\";i:9935;s:6:\"reason\";s:0:\"\";}}"],"_bbp_topic_id":["390449"],"_bbp_forum_id":["27791"],"_bbp_engagement":["20905","465704"],"_bbp_voice_count":["2"],"_bbp_reply_count":["10"],"_bbp_last_reply_id":["407450"],"_bbp_last_active_id":["407450"],"_bbp_last_active_time":["2025-01-28 19:20:09"]},"test":"reddyramu-gundloorustud-hs-flensburg-de"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/390449","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":1,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/390449\/revisions"}],"predecessor-version":[{"id":390638,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/390449\/revisions\/390638"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=390449"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}