


{"id":451947,"date":"2026-02-04T03:04:16","date_gmt":"2026-02-04T03:04:16","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/ale-axisymmetric-simulation-in-ls-dyna-with-volume-fraction-geometry\/"},"modified":"2026-02-04T03:04:16","modified_gmt":"2026-02-04T03:04:16","slug":"ale-axisymmetric-simulation-in-ls-dyna-with-volume-fraction-geometry","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/ale-axisymmetric-simulation-in-ls-dyna-with-volume-fraction-geometry\/","title":{"rendered":"ALE axisymmetric simulation in LS-DYNA with volume fraction geometry?"},"content":{"rendered":"<p>&lt;p&gt;When I am using the workbench, there is no option of ALE bodies under model. So i thought that using the LS Prepost might work. So I have imported the mesh from the workbench together with the keyword file. Then I made ALE2D and so on.&lt;br&gt;The issue comes from material groups and used Volume fraction geometry to &#8220;patch&#8221; the bodies in the background domain. So firstly it needs some VOID parts, I have created them but it does not seem that Volume fraction geometry lets me input them. But for some reason presense of those eliminate the &#8220;cannot find void body&#8221; error. Then I am keep getting&lt;br&gt;&lt;br&gt;&nbsp;*** Error 21153 (STR+1153)&lt;br&gt;&nbsp; &nbsp; &nbsp;Flag BAMMG = 2 specified in card *INITIAL_VOLUME_FRACTION_GEOMETRY&lt;br&gt;&nbsp; &nbsp; &nbsp;is out of range. It is an ALE AMMG ID and its value should&lt;br&gt;&nbsp; &nbsp; &nbsp;be greater than 1 and less than 1.&lt;br&gt;&lt;br&gt;I have tried switching the ID of the AMMG around, from 1 to 4, but it would only show up as 2, 22, or something.&nbsp;&lt;br&gt;Does anyone know what is going on? ID being greater than 1 and less than 1 means it cannot be 1, but it is not 1.&lt;br&gt;&lt;br&gt;(The following pic is me putting BAMMG on 1, same error message)&nbsp;&lt;br&gt;<img decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2026\/02\/04-02-2026-1770173792-mceclip0.png\" \/>&lt;br&gt;&lt;br&gt;I am just confused how would you run a axisymmetric ALE simulation in ls dyna in general,&nbsp;&lt;br&gt;I was thinking&nbsp;&lt;br&gt;1) make mesh in workbench since its easier and do all the setup that is avaliable&nbsp;&lt;br&gt;2) import into LS dyna and they all come as shell bodies due to unavaliability of ALE, change them all to ALE2D&lt;br&gt;3) use volume fraction geometry to patch them on the ALE background that we made before in workbench (already ALE2d)&lt;br&gt;&lt;br&gt;Idk why this doesnt work.&nbsp;&lt;br&gt;The issue of me not making mesh in ls dyna is because the shape I am tyring to run is irregular, and very hard to draw in ls dyna.&nbsp;&lt;br&gt;Do i need to do something with the axis of symmetry? Doesn&#8217;t it already transfer write together with the workbench written k file? What about boundary?&nbsp;&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-451947","topic","type-topic","status-publish","hentry","topic-tag-2d-axisymmetric","topic-tag-ale","topic-tag-volume-fraction"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_forum_id":["27814"],"_bbp_topic_id":["451947"],"_bbp_author_ip":["131.151.41.49"],"_bbp_last_reply_id":["452995"],"_bbp_last_active_id":["452995"],"_bbp_last_active_time":["2026-02-20 07:32:13"],"_bbp_reply_count":["5"],"_bbp_reply_count_hidden":["0"],"_bbp_voice_count":["3"],"_bbp_engagement":["602335","88","654102"],"_btv_view_count":["154"],"_bbp_topic_status":["unanswered"],"_bbp_subscription":["602335","88","654102"]},"test":"gl6fpumsystem-edu"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/451947","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\/451947\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=451947"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}