{"id":41383,"date":"2020-03-01T12:01:11","date_gmt":"2020-03-01T12:01:11","guid":{"rendered":"\/forum\/forums\/topic\/free-free-modal-analysis-first-6-modes\/"},"modified":"2020-03-01T12:01:11","modified_gmt":"2020-03-01T12:01:11","slug":"free-free-modal-analysis-first-6-modes","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/free-free-modal-analysis-first-6-modes\/","title":{"rendered":"Free-Free Modal Analysis, First 6 Modes"},"content":{"rendered":"<p>Hello,<\/p>\n<p><\/p>\n<p>I have been trying to solve modal analysis for a model which I am later going to investigate the response under forced vibration. Since the moda analysis I am conducting is free-free, I was expecting to get th first six modes 0 or close to 0. Yet the results for the 4th,5th and6th modes frequencies (can be seen in the attachment) are figures such as 10-20 Hz. The modes seem like rigid body modes but I can not be sure if the solution is correct.<\/p>\n<p><\/p>\n<p>After simplifying the model (which is not acceptable for the purpose, just to see the change) and uniting the bodies with boolean method, I get the results I expected; first 3 modes 0 and other 3 modes close to zero.<\/p>\n<p><\/p>\n<p>I am suspecting this behaviour is somewhat related to the mesh settings and element type since I am sure the geometry does not have problems such as intersecting bodies etc.<\/p>\n<p><\/p>\n<p>&nbsp;Could anyone help me with this matter?<\/p>\n<p><\/p>\n<p>Thanks in advance.<\/p>\n","protected":false},"template":"","class_list":["post-41383","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_old_topic_id":["13563"],"_bbp_old_topic_author_name_id":["Anonymous"],"_bbp_old_is_topic_anonymous_id":["false"],"_bbp_old_closed_status_id":["publish"],"_bbp_author_ip":[null],"_bbp_old_sticky_status_id":["normal"],"_bbp_likes_count":["0"],"_btv_view_count":["3425"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["41383"],"_bbp_forum_id":["27791"],"_bbp_engagement":["240","173864"],"_bbp_voice_count":["2"],"_bbp_reply_count":["2"],"_bbp_last_reply_id":["106621"],"_bbp_last_active_id":["106621"],"_bbp_last_active_time":["2020-03-01 14:08:03"]},"test":"alperen"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/41383","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\/41383\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=41383"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}