{"id":163503,"date":"2021-10-28T16:17:26","date_gmt":"2021-10-28T16:17:26","guid":{"rendered":"\/forum\/forums\/topic\/for-analysis-of-flow-over-cylinder-or-sphere-in-2d-how-does-ansys-knows-its-sphere-or-cylinder\/"},"modified":"2021-12-03T15:31:24","modified_gmt":"2021-12-03T15:31:24","slug":"for-analysis-of-flow-over-cylinder-or-sphere-in-2d-how-does-ansys-knows-its-sphere-or-cylinder","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/for-analysis-of-flow-over-cylinder-or-sphere-in-2d-how-does-ansys-knows-its-sphere-or-cylinder\/","title":{"rendered":"For analysis of flow over cylinder or sphere in 2D- How does ANSYS knows it&#8217;s sphere or cylinder."},"content":{"rendered":"<div class=\"Item-Body\">\n<div class=\"Message userContent\">\n<p>I had this question in my mind for the past few days. In case if I simulate the flow over the cylinder and I wish to perform 2D analysis I guess the results (coefficient of lift and drag) won&#039;t match with either case (analytical results of cylinder and sphere)<\/p>\n<p>A similar thing happened when I did analysis for lumped analysis for sphere (circle in 2D) and walls of the circle are given temperature boundary conditions with heat transfer coefficient calculated from Biot formula. I found that the area-weighted average of temperature doesn&#039;t match with analytical values if I take the characteristic length as the radius. <strong>Why in this case characteristic length is radius instead of R\/3.<\/strong> I have seen many online resources and many have taken Lc = R. So I finally got the answer with I took the 3D model and solved it (here Lc = R was taken).<\/p>\n<p><\/p>\n<\/p>\n<p>I am stuck in a similar condition where I need to analyze the flow over the sphere. What are the<strong> procedures to find the coefficient of lift and drag if ANSYS cannot decide between sphere and cylinder?<\/strong> Is it viable to find lift and drag force then convert to lift and drag coefficient? Else do I need to perform 3D analysis.<\/p>\n","protected":false},"template":"","class_list":["post-163503","topic","type-topic","status-closed","hentry","topic-tag-aerodynamics","topic-tag-cylinder","topic-tag-fluent","topic-tag-sphere"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_author_ip":[""],"_bbp_old_reply_author_name_id":["Anonymous"],"_bbp_old_is_reply_anonymous_id":["false"],"_btv_view_count":["2627"],"_bbp_likes_count":["0"],"_bbp_subscription":["236860"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["163503"],"_bbp_forum_id":["27792"],"_bbp_engagement":["199","158298"],"_bbp_voice_count":["2"],"_bbp_reply_count":["19"],"_bbp_last_reply_id":["196175"],"_bbp_last_active_id":["196175"],"_bbp_last_active_time":["2021-12-03 15:31:24"]},"test":"ananth-narayan"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/163503","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\/163503\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=163503"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}