{"id":318520,"date":"2023-11-20T14:08:08","date_gmt":"2023-11-20T14:08:08","guid":{"rendered":"\/forum\/?post_type=topic&#038;p=318520"},"modified":"2023-11-21T14:29:43","modified_gmt":"2023-11-21T14:29:43","slug":"modal-response-of-membrane-subjected-to-uniform-pressure","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/modal-response-of-membrane-subjected-to-uniform-pressure\/","title":{"rendered":"Modal response of membrane subjected to uniform pressure"},"content":{"rendered":"<p>I am attempting to evaluate the modal response of a pressurized membrane-like structure.<\/p>\n<p>I have created a simple example consisting of a square membrane, simply supported along the edges, and subjected to uniform pressure. Here are some additional details:<\/p>\n<ol>\n<li>\n<p>I am utilizing a fully integrated Belytschko-Tsay membrane (ELFORM=9) that is designed to be hourglass-free.<\/p>\n<\/li>\n<li>\n<p>I am using a linear elastic material (*MAT_ELASTIC).<\/p>\n<\/li>\n<li>\n<p>The pressure load is applied using the *LOAD_SHELL_SET_ID keyword.<\/p>\n<\/li>\n<li>\n<p>Currently, I have opted for the explicit solver, applying the pressure linearly.<\/p>\n<\/li>\n<li>\n<p>I am constraining the translational degrees of freedom (DOF) of the edges only.<\/p>\n<\/li>\n<li>\n<p>I am using version R13.1.1-13-g5480eca294 mpp_dp for Windows.<\/p>\n<\/li>\n<\/ol>\n<p>Upon running the simulation, I immediately observe what I thin kto be significant hourglassing in the membrane deformation and am unsure about the cause (please see the attached picture).<\/p>\n<p>How can I suppress this behavior? What is causing it?<\/p>\n<p>&nbsp;<\/p>\n<p>Best regards,<\/p>\n<p>Rocco<\/p>\n<p><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/11\/20-11-2023-1700488526-mceclip0.png\"><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/11\/20-11-2023-1700489171-mceclip0.png\" width=\"678\" height=\"98\"><\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n","protected":false},"template":"","class_list":["post-318520","topic","type-topic","status-closed","hentry","topic-tag-2dmaterialsandmetals-1","topic-tag-lsdyna","topic-tag-membrane-elements-1"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_author_ip":["23.206.193.41"],"_bbp_subscription":["302593"],"_btv_view_count":["561"],"_bbp_status":["publish"],"_bbp_topic_status":["unanswered"],"_bbp_topic_id":["318520"],"_bbp_forum_id":["27814"],"_bbp_engagement":["302593"],"_bbp_voice_count":["1"],"_bbp_reply_count":["2"],"_bbp_last_reply_id":["318672"],"_bbp_last_active_id":["318672"],"_bbp_last_active_time":["2023-11-20 17:55:03"]},"test":"r-bombardiericira-it"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/318520","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\/318520\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=318520"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}