{"id":278529,"date":"2023-04-08T15:32:01","date_gmt":"2023-04-08T15:32:01","guid":{"rendered":"\/forum\/forums\/topic\/modal-analysis-using-point-mass\/"},"modified":"2024-01-11T14:44:28","modified_gmt":"2024-01-11T14:44:28","slug":"modal-analysis-using-point-mass","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/modal-analysis-using-point-mass\/","title":{"rendered":"Modal Analysis using point mass"},"content":{"rendered":"<p>Hi community,<\/p>\n<p>I have done a modal analysis of a container in which a fluid is considered as a point mass. This point mass is defined using free standing remote point. Free-free modal case is considered. After calculation for 20 modes, I find out that 6 modes are zero and additional 7th, 8th and 9th mode frequencies are almost zero. Why the 7th, 8th and 9th modes are also zero when first six modes capture rigid body motion? Following are the snapshots of the analysis.<\/p>\n<p>1) Geometry<\/p>\n<p><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/04\/08-04-2023-1680967576-Geom1.jpg\" alt=\"\"><\/p>\n<p>2) Remote point<\/p>\n<p><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/04\/08-04-2023-1680967676-RemotePoint1.jpg\" alt=\"\"><\/p>\n<p>3) Point mass<\/p>\n<p><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/04\/08-04-2023-1680967703-PointMass1.jpg\" alt=\"\"><\/p>\n<p>4) Mode and frequency<\/p>\n<p><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/04\/08-04-2023-1680967738-Modes1.jpg\" alt=\"\"><\/p>\n<p>Your suggestions for any modifications in analysis are most welcome.<\/p>\n<p>Regards,<\/p>\n<p>Rohan.<\/p>\n","protected":false},"template":"","class_list":["post-278529","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["281630","240"],"_bbp_author_ip":["23.192.164.18"]," _bbp_last_reply_id":["0"]," _bbp_likes_count":["0"],"_btv_view_count":["3154"],"_bbp_topic_status":["answered"],"_bbp_topic_id":["278529"],"_bbp_forum_id":["27791"],"_bbp_engagement":["240","281630"],"_bbp_voice_count":["2"],"_bbp_reply_count":["7"],"_bbp_last_reply_id":["279020"],"_bbp_last_active_id":["279020"],"_bbp_last_active_time":["2023-04-12 11:11:38"]},"test":"rohan-pawarzeusnumerix-com"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/278529","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\/278529\/revisions"}],"predecessor-version":[{"id":344280,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/278529\/revisions\/344280"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=278529"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}