{"id":291522,"date":"2023-07-04T19:04:52","date_gmt":"2023-07-04T19:04:52","guid":{"rendered":"\/forum\/forums\/topic\/rayleigh-damping-during-explicit-simulation\/"},"modified":"2023-07-06T22:17:51","modified_gmt":"2023-07-06T22:17:51","slug":"rayleigh-damping-during-explicit-simulation","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/rayleigh-damping-during-explicit-simulation\/","title":{"rendered":"Rayleigh Damping for explicit dynamics"},"content":{"rendered":"<p><span style=\"font-size: 12pt\">Hi everyone,<\/span><\/p>\n<p><span style=\"font-size: 12pt\">We are trying to use the Rayleigh Damping model for an explicit simulation case in LS-Dyna. However, we are facing some issues with the Stiffness Proportional damping which can be implemented with the *DAMPING_PART_STIFFNESS. For the implicit case, the implementation is pretty straightforward &#8211; setting the calculated beta coefficient as negative solves the system correctly.<\/span><\/p>\n<p><span style=\"font-size: 12pt\">However, for explicit analysis, setting the beta as negative can solve the system for high frequency motions but gives erroneous results for lower frequencies. The applied motion of the explicit case was assumed to be damped for frequencies ranging from 1 to 10Hz. We found through some simplified analysis that for this case, the Rayleigh damping result through implicit and explicit analysis is different. Hence, we are confused if there is &#8220;actually&#8221; a way to implement the Rayleigh damping model in LS-Dyna. Otherwise we might need to solve the problem implicitly, which will be a nightmare considering the contact surfaces and assemblies we have modeled.<\/span><\/p>\n<p><span style=\"font-size: 12pt\">I would really appreciate it if anyone could help us with this.<\/span><\/p>\n<p><span style=\"font-size: 12pt\">Thank you.<\/span><\/p>\n<p><span style=\"font-size: 12pt\">&#8211; Tonmoy<\/span><\/p>\n","protected":false},"template":"","class_list":["post-291522","topic","type-topic","status-closed","hentry","topic-tag-damping-coefficient","topic-tag-ls-dyna","topic-tag-LS-DynaSolverExplicitDynamics-1","topic-tag-rayleighs-damping"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["273386","3136"],"_bbp_author_ip":["23.33.28.199"]," _bbp_last_reply_id":["0"]," _bbp_likes_count":["0"],"_btv_view_count":["2213"],"_edit_lock":["1688580392:203800"],"_bbp_status":["publish"],"_bbp_topic_status":["unanswered"],"_bbp_topic_id":["291522"],"_bbp_forum_id":["27814"],"_bbp_engagement":["3136","273386"],"_bbp_voice_count":["2"],"_bbp_reply_count":["5"],"_bbp_last_reply_id":["291968"],"_bbp_last_active_id":["291968"],"_bbp_last_active_time":["2023-07-06 22:15:26"]},"test":"tonmoymailinator-com"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/291522","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\/291522\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=291522"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}