{"id":240505,"date":"2022-11-11T13:49:47","date_gmt":"2022-11-11T13:49:47","guid":{"rendered":"\/forum\/forums\/topic\/dual-cell-model-ntu-value\/"},"modified":"2022-11-11T13:49:47","modified_gmt":"2022-11-11T13:49:47","slug":"dual-cell-model-ntu-value","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/dual-cell-model-ntu-value\/","title":{"rendered":"Dual Cell Model NTU value"},"content":{"rendered":"<p>Hi,<\/p>\n<p>I am trying to analyze a heat exchanger(as in image) that have too much fins. One of the sides is air and the other is water. Because of the complexity of geometry, i decided to analyze with dual cell model. I took a tiny slice from heat exchanger geometry and analyzed parametrically (the parameter was mass flow rate). Then to use dual cell model, i simplified complex geometry taking an example from second image, i removed fins from air side and removed tubes from water side on the geometry. I defined porous zone both air and water sides, I took massflow-dependent heat transfer results and transfer to heat transfer data tab(raw-data tab). Then i analyzed the simplified geometry. But i encountered the prompt that says:<\/p>\n<p>NTU value at max. (50) iteration = 4.97639, percent error = 3.9016e-12<\/p>\n<p>Program gives that error every iteration. Although there is an error iterations continue. There is something wrong but i don&#8217;t know what it is.<\/p>\n<p>Is the path that i following for solution right?<br \/>What does that error mean?<\/p>\n<p>I will be appreciated if anyone help me.<\/p>\n<p>I use Ansys Fluent 2021 R2.<\/p>\n<p><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2022\/11\/11-11-2022-1668172916-tube_fin.png\" alt=\"\"><img decoding=\"async\" style=\"font-size: 14pt\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2022\/11\/11-11-2022-1668173183-dual cell model.PNG\" alt=\"\"><\/p>\n","protected":false},"template":"","class_list":["post-240505","topic","type-topic","status-closed","hentry","topic-tag-fluent-cfd-ansys-1","topic-tag-heat_exchanger-1","topic-tag-coupled-2","topic-tag-dual-cell-1","topic-tag-error","topic-tag-heat","topic-tag-heat-transfer","topic-tag-mesh-heat","topic-tag-steady-state"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["267437","15977"],"_bbp_author_ip":["23.223.149.174"]," _bbp_last_reply_id":["0"]," _bbp_likes_count":["0"],"_btv_view_count":["1110"],"_bbp_likes_count":["1"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["240505"],"_bbp_forum_id":["27792"],"_bbp_engagement":["15977","267437"],"_bbp_voice_count":["2"],"_bbp_reply_count":["2"],"_bbp_last_reply_id":["241348"],"_bbp_last_active_id":["241348"],"_bbp_last_active_time":["2022-11-18 11:57:50"]},"test":"ysfuznx1998gmail-com"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/240505","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\/240505\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=240505"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}