{"id":362767,"date":"2024-04-17T17:59:41","date_gmt":"2024-04-17T17:59:41","guid":{"rendered":"\/forum\/forums\/reply\/362767\/"},"modified":"2024-04-17T17:59:41","modified_gmt":"2024-04-17T17:59:41","slug":"362767","status":"publish","type":"reply","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/reply\/362767\/","title":{"rendered":"Reply To: fluid model displacement factor"},"content":{"rendered":"<p>&lt;p&gt;Dear ido and Ushnish,&lt;\/p&gt;&lt;p&gt;&nbsp;&lt;\/p&gt;&lt;p&gt;I have an important question about this topic. I want to apply the earthquake in z direction to the tank fill of water with the box floating on it like top figure. I add one more picture to show it better here. I need to first gravity initialize the box and after it reached equilibrium, I am going to apply earthquake just in Z direction. It is basically two step. Step one, from 0 to 5 second, I just apply graviry through a inclined curve and then apply earquake at 5 second ( the acceleration that I provided starts after 5 second). My problem is that I need the base of the tank to be fixed in z direction in order to gravity initiation, but for the next step that I want to apply acceleration in z direction, I need that DOF in z direction to be free. If I fix DOF in z direction, my tank doesn&#8217;t more in z direction when earthquake applies but the first step (gravity initialization) reaches equilibrium and the problem with having the DOF in z direction free, it doesn&#8217;t converge in the gravity initialization and box starts to rotate. Do you have any solution for me? I did the same thing for Y direction and the results were successful because for applying earthquake in y direction, I don&#8217;t need to free the DOF in z direction free and I could get reasonable response. Appreciate any suggestions.&nbsp;&lt;\/p&gt;&lt;p&gt;<img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2024\/04\/17-04-2024-1713376777-mceclip0.png\" \/>&lt;\/p&gt;&lt;p&gt;Thanks a lot&lt;\/p&gt;&lt;p&gt;Maryam&nbsp;&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-362767","reply","type-reply","status-publish","hentry"],"aioseo_notices":[],"acf":[],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/replies\/362767","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/replies"}],"about":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/types\/reply"}],"version-history":[{"count":0,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/replies\/362767\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=362767"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}