{"id":45335,"date":"2020-06-21T11:09:36","date_gmt":"2020-06-21T11:09:36","guid":{"rendered":"\/forum\/forums\/topic\/fluent-convergence-issues-steady-state-natural-convection\/"},"modified":"2020-06-21T11:09:36","modified_gmt":"2020-06-21T11:09:36","slug":"fluent-convergence-issues-steady-state-natural-convection","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/fluent-convergence-issues-steady-state-natural-convection\/","title":{"rendered":"Fluent Convergence Issues &#8211; Steady State Natural Convection"},"content":{"rendered":"<p>Hello all,<\/p>\n<p><\/p>\n<p>I&#8217;m having convergence issues when simulating steady-state natural convection between a small cylinder inside of a box and the air inside. The geometry is fairly simple, I&#8217;m really doing this as an exercise to see how much energy is transmitted through the different sides of the box and what the steady-state temperature rise in the box is, but I have trouble meeting the convergence criteria for my simulation. My criteria isn&#8217;t overly restrictive, and when I view results after a non-converged simulation, results are clearly unrealistic. I seem to be making all the appropriate analysis choices, but still have trouble.<\/p>\n<p><\/p>\n<p>How big of a factor is the mesh quality\/configuration in my convergence issues? I seem to think my mesh is the issue, but even when I refine cells around the flow boundary layers, it seems there is no difference in results.<\/p>\n<p><\/p>\n<p>Parameters relevant to my issue are as follows:<\/p>\n<p><\/p>\n<ul><\/p>\n<li>Cylinder is 2&#8243; long, 0.5&#8243; diameter, located inside a 10&#8243; x 10&#8243; x 10&#8243; steel box<\/li>\n<p><\/p>\n<li>Cylinder generates 17 W of power<\/li>\n<p><\/p>\n<li>Fluid inside box is air at atmospheric pressure<\/li>\n<p><\/p>\n<li>Ambient air outside of box is constant 60 deg. F<\/li>\n<p><\/p>\n<li>Flow is laminar<\/li>\n<p>\n<\/ul>\n<p><\/p>\n<p>Thanks for any advice\/experience!<\/p>\n<p><\/p>\n<p>-Justin<\/p>\n","protected":false},"template":"","class_list":["post-45335","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_old_topic_id":["17516"],"_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":["1688"],"_bbp_subscription":["252894"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["45335"],"_bbp_forum_id":["27792"],"_bbp_engagement":["25","118","199","178771"],"_bbp_voice_count":["4"],"_bbp_reply_count":["10"],"_bbp_last_reply_id":["119423"],"_bbp_last_active_id":["119423"],"_bbp_last_active_time":["2020-06-29 14:03:08"]},"test":"jmwarre2"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/45335","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\/45335\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=45335"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}