{"id":436131,"date":"2025-07-05T04:59:51","date_gmt":"2025-07-05T04:59:51","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/something-that-makes-the-pattern-disappear-after-contact\/"},"modified":"2025-07-05T04:59:51","modified_gmt":"2025-07-05T04:59:51","slug":"something-that-makes-the-pattern-disappear-after-contact","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/something-that-makes-the-pattern-disappear-after-contact\/","title":{"rendered":"something that makes the pattern disappear after contact"},"content":{"rendered":"<p>&lt;p&gt;Hi everyone,&nbsp;&lt;\/p&gt;&lt;p&gt;I&#8217;m a student and I&#8217;m learning about LS-DYNA.&lt;\/p&gt;&lt;p&gt;I&#8217;m simulating a drop test, where Part 1 is falling onto Part 2.&lt;br&gt;Part 1 is only assigned gravity, and Part 2 is fixed in all 6 degrees of freedom.&lt;\/p&gt;&lt;p&gt;After Part 1 starts interacting with Part 2, Part 2 disappears after a short period of contact.&lt;br&gt;Does anyone know what might be causing this?&lt;\/p&gt;&lt;p&gt;One notable point is that Part 2 is assigned a soft material.&lt;br&gt;At first, I used MAT_057 (MAT_LOW_DENSITY_FOAM) with 3D solid elements, and the results looked fine.&lt;br&gt;Later, I changed the model to use 2D shell elements.&lt;br&gt;I noticed that MAT_057 gave errors with shell elements, so I switched to MAT_181 (MAT_SIMPLIFIED_RUBBER\/FOAM) and that&rsquo;s when the issue started.&lt;\/p&gt;&lt;p&gt;Thanks a lot in advance!&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-436131","topic","type-topic","status-publish","hentry","topic-tag-foam-1","topic-tag-material"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_forum_id":["27814"],"_bbp_topic_id":["436131"],"_bbp_subscription":["503449","480261","492369"],"_bbp_author_ip":["202.18.108.232"],"_bbp_last_reply_id":["436410"],"_bbp_last_active_id":["436410"],"_bbp_last_active_time":["2025-07-09 14:53:44"],"_bbp_reply_count":["3"],"_bbp_reply_count_hidden":["0"],"_bbp_voice_count":["3"],"_bbp_engagement":["503449","480261","492369"],"_btv_view_count":["342"],"_bbp_topic_status":["unanswered"]},"test":"7bc276500e7e85b24fdb9a8bc476544e983b3d2d"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/436131","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\/436131\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=436131"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}