{"id":343109,"date":"2024-01-04T09:41:19","date_gmt":"2024-01-04T09:41:19","guid":{"rendered":"\/forum\/forums\/topic\/free-falling-of-a-disk-in-fluent\/"},"modified":"2024-01-04T09:41:19","modified_gmt":"2024-01-04T09:41:19","slug":"free-falling-of-a-disk-in-fluent","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/free-falling-of-a-disk-in-fluent\/","title":{"rendered":"Free falling of a disk in FLUENT"},"content":{"rendered":"<p>Hi,&nbsp;<br \/>Problem: Free falling of a disk in water<br \/>I want to simulate the free falling of a disk in a water tank located under the free surface. The disk diameter is 5 cm, the tank is 30*30 cm, and the height of the tank, which is filled with water, is 1m. I used the 6-DOF method; I simulated the case as the working fluid was air without any problem.! But as I changed it to water, I couldn&#8217;t get any converged solution. I tried both the overset mesh method and dynamic mesh, but still, I can&#8217;t solve this case! Also, I used the VOF model to consider the air and free surface, (primary fluid is air, and operation density was considered 1.225 (air), also 0 was tried). By the VOF model, there is a relatively good convergency, but during the solution, it will diverge even the CFL number is less than 0.01 (time step size about 10^-5).<br \/>I tried the SIMPLE and Couple methods for pressure and velocity field coupling, but they didn&#8217;t work; it seems due to the high viscosity and density of water, which are higher than air, some points are need to be considered in the simulation.<br \/>Could you help me? Do you have any suggestions\/comments?<\/p>\n","protected":false},"template":"","class_list":["post-343109","topic","type-topic","status-closed","hentry","topic-tag-fluent-cfd-ansys-1","topic-tag-6dof-solver","topic-tag-dynamic-mesh"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["336069","15180","340784"],"_bbp_author_ip":["23.206.193.59"]," _bbp_last_reply_id":["0"]," _bbp_likes_count":["0"],"_btv_view_count":["519"],"_bbp_topic_status":["unanswered"],"_bbp_topic_id":["343109"],"_bbp_forum_id":["27792"],"_bbp_engagement":["15180","336069"],"_bbp_voice_count":["2"],"_bbp_reply_count":["2"],"_bbp_reply_count_hidden":["1"],"_bbp_last_reply_id":["343289"],"_bbp_last_active_id":["343289"],"_bbp_last_active_time":["2024-01-05 03:21:43"]},"test":"farzadpourfattahgmail-com"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/343109","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\/343109\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=343109"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}