{"id":366484,"date":"2024-05-11T05:02:32","date_gmt":"2024-05-11T05:02:32","guid":{"rendered":"\/forum\/forums\/topic\/input-a-b-d-e-f-matrix-for-shell99\/"},"modified":"2024-05-11T05:02:32","modified_gmt":"2024-05-11T05:02:32","slug":"input-a-b-d-e-f-matrix-for-shell99","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/input-a-b-d-e-f-matrix-for-shell99\/","title":{"rendered":"input A B D E F matrix for SHELL99"},"content":{"rendered":"<p>I have some problems when using shell99 element keyopt2,3, I input A B D E F matrix, and ensure that they are positive definite, but when calculating, ansys prompts an error,<\/p>\n<p>*** ERROR ***&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;CP =&nbsp; &nbsp; &nbsp; &nbsp;9.406&nbsp; &nbsp;TIME= 10:53:01<br \/>&nbsp;Input matrix of element 1 is not positive semi-definite.&nbsp; Check real&nbsp; &nbsp;&nbsp;<br \/>&nbsp;constant table 1.&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<\/p>\n<p>how to solve it<br \/>Here&#8217;s what I wrote about apdl<\/p>\n<p>\/prep7<br \/>ESEL,s,elem,,&nbsp; &nbsp; &nbsp; &nbsp;1,&nbsp; &nbsp; &nbsp; &nbsp;1,&nbsp; &nbsp; 1600<br \/>ET,&nbsp; &nbsp; &nbsp; &nbsp;1,99<br \/>KEYOPT,&nbsp; &nbsp; &nbsp; &nbsp;1,2,3<br \/>R,&nbsp; &nbsp; &nbsp; &nbsp; 1,&nbsp; 0.10000000E+12<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,2,&nbsp; 0.91158854E+02<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,4,&nbsp; 0.21316282E-13<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,7,&nbsp; 0.10000000E+11<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,9,&nbsp; 0.26645353E-14<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,12,&nbsp; 0.10000000E+11<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,16,&nbsp; 0.10000000E+11<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,19,&nbsp; 0.10000109E+11<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,21,&nbsp; 0.10000109E+11<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,22,&nbsp; 0.10000002E+10<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,23, -0.68903426E+02<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,25,&nbsp; 0.94291151E+02<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,28,&nbsp; 0.99999998E+09<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,30,&nbsp; 0.38613569E+02<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,33,&nbsp; 0.10000000E+10<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,37,&nbsp; 0.99999993E+09<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,40,&nbsp; 0.99993110E+09<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,42,&nbsp; 0.99993110E+09<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,43,&nbsp; 0.10000000E+11<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,44,&nbsp; 0.43756250E+02<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,46,&nbsp; 0.52558450E+01<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,49,&nbsp; 0.10000000E+11<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,51,&nbsp; 0.68758909E+00<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,54,&nbsp; 0.10000000E+11<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,58,&nbsp; 0.10000000E+11<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,61,&nbsp; 0.10000052E+11<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,63,&nbsp; 0.10000052E+11<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,64,&nbsp; 0.10000005E+10<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,65, -0.19689154E+03<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,67, -0.52614462E+03<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,70,&nbsp; 0.99999994E+09<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,72, -0.21546371E+03<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,75,&nbsp; 0.10000000E+10<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,79,&nbsp; 0.99999980E+09<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,82,&nbsp; 0.99980311E+09<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,84,&nbsp; 0.99980311E+09<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,85,&nbsp; 0.10000000E+11<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,86,&nbsp; 0.37805400E+02<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,88,&nbsp; 0.14545551E+02<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,91,&nbsp; 0.10000000E+11<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,93,&nbsp; 0.19029028E+01<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,96,&nbsp; 0.10000000E+11<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,100,&nbsp; 0.10000000E+11<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,103,&nbsp; 0.10000045E+11<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,105,&nbsp; 0.10000045E+11<br \/>RMODIF,&nbsp; &nbsp; &nbsp; &nbsp; 1,125,&nbsp; 0.24000000E+01<br \/>EMODIF,ALL,REAL,&nbsp; &nbsp; &nbsp; &nbsp;1<br \/>EMODIF,ALL,TYPE,&nbsp; &nbsp; &nbsp; &nbsp;1<\/p>\n","protected":false},"template":"","class_list":["post-366484","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["348534","262801","88"],"_bbp_author_ip":["184.24.96.207"]," _bbp_last_reply_id":["0"]," _bbp_likes_count":["0"],"_bbp_likes_count":["2"],"_btv_view_count":["371"],"_bbp_topic_status":["unanswered"],"_bbp_topic_id":["366484"],"_bbp_forum_id":["27791"],"_bbp_engagement":["88","262801","348534"],"_bbp_voice_count":["3"],"_bbp_reply_count":["5"],"_bbp_last_reply_id":["368413"],"_bbp_last_active_id":["368413"],"_bbp_last_active_time":["2024-05-24 03:05:11"]},"test":"fangpcmail-nwpu-edu-cn"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/366484","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\/366484\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=366484"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}