{"id":280989,"date":"2023-04-24T14:55:05","date_gmt":"2023-04-24T14:55:05","guid":{"rendered":"\/forum\/forums\/topic\/simulating-fluid-flow-in-a-bifurcating-tube\/"},"modified":"2023-04-24T14:55:05","modified_gmt":"2023-04-24T14:55:05","slug":"simulating-fluid-flow-in-a-bifurcating-tube","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/simulating-fluid-flow-in-a-bifurcating-tube\/","title":{"rendered":"Simulating fluid flow in a bifurcating tube"},"content":{"rendered":"<p>Hello,<\/p>\n<p>I am working on a FSI model of fluid flow in a bifurcating tube with added cyclic loading on the outer surface of the tube. I have simulated the model without added load and it ran smoothly. Before applying the full cyclic load, i fugred i should test how the tube would react to a normal load. When i ran the simulation with the following loading condition i ran into an error that states &#8220;update dynamic mesh failed. negative cell volume detected&#8221;. I have tried several things to resolve the issue:<\/p>\n<p>1- Decreasing the time step size.<\/p>\n<p>2- Decreasing element size in fluid and solid domain.<\/p>\n<p>3- Mesh refinement for the tube model.<\/p>\n<p>4- Adding a meshing method to the fluid mesh (Hex Dominant).<\/p>\n<p>5- Inflation at the walls of the fluid domain.<\/p>\n<p>The last thing i tried was reducing the load. Although that worked, the deformation of the tube at that point was very small that it did not affect the fluid domain.<\/p>\n<p>I have attached a picture of the results obtained from the FSI run without loading, a picture of the load position and value that worked, pictures of the meshing conditions i applied for the no-load run. the tube is of a hyper elastic material.<\/p>\n<p><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/04\/24-04-2023-1682347814-Screenshot (44).png\" alt=\"\"><\/p>\n<p><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/04\/24-04-2023-1682347839-Screenshot (45).png\" alt=\"\"><\/p>\n<p><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/04\/24-04-2023-1682347863-Screenshot (46).png\" alt=\"\"><\/p>\n<p><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/04\/24-04-2023-1682347879-Screenshot (47).png\" alt=\"\"><\/p>\n","protected":false},"template":"","class_list":["post-280989","topic","type-topic","status-closed","hentry","topic-tag-2-way-coupled-fsi","topic-tag-ansys-cfd-1","topic-tag-transient-structural"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["273197","805","240"],"_bbp_author_ip":["23.220.96.180"]," _bbp_last_reply_id":["0"]," _bbp_likes_count":["0"],"_btv_view_count":["594"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["280989"],"_bbp_forum_id":["27791"],"_bbp_engagement":["240","805","273197"],"_bbp_voice_count":["3"],"_bbp_reply_count":["4"],"_bbp_last_reply_id":["281748"],"_bbp_last_active_id":["281748"],"_bbp_last_active_time":["2023-04-30 22:39:19"]},"test":"fia11mail-aub-edu"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/280989","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\/280989\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=280989"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}