{"id":318243,"date":"2023-11-17T16:58:13","date_gmt":"2023-11-17T16:58:13","guid":{"rendered":"\/forum\/forums\/topic\/incorrect-cl-calculation-in-fluent\/"},"modified":"2023-11-17T16:58:13","modified_gmt":"2023-11-17T16:58:13","slug":"incorrect-cl-calculation-in-fluent","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/incorrect-cl-calculation-in-fluent\/","title":{"rendered":"incorrect cl calculation in fluent?!"},"content":{"rendered":"<p>using the default report definitions in fluent (shown below), testing an ahmed body i&#8217;m getting a cl of ~0.34, very close to experimental,<\/p>\n<p>However if you put the lift force (~181N) and the top projected reference area (3.25m^2) and velocity (30m\/s) to work out the lift coef, it comes out at about 0.1.<\/p>\n<p>If you use the front projected area (0.988m^2) instead you get cl ~0.33, which seems to mean its using the front projected area to calculate lift coefficant? shouldn&#8217;t it use top projected area? and if yes why is the cl so far off experimental?<\/p>\n<p>(z axis is forward, not x)<\/p>\n<p><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/11\/17-11-2023-1700240051-mceclip0.png\"><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/11\/17-11-2023-1700240100-mceclip1.png\"><\/p>\n<p>&nbsp;<\/p>\n<p><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/11\/17-11-2023-1700240141-mceclip2.png\"><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/11\/17-11-2023-1700240178-mceclip3.png\"><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2023\/11\/17-11-2023-1700240254-mceclip4.png\"><\/p>\n","protected":false},"template":"","class_list":["post-318243","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["271665","13659","730"],"_bbp_author_ip":["23.206.193.154"]," _bbp_last_reply_id":["0"]," _bbp_likes_count":["0"],"_btv_view_count":["408"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["318243"],"_bbp_forum_id":["27792"],"_bbp_engagement":["730","13659","271665"],"_bbp_voice_count":["3"],"_bbp_reply_count":["2"],"_bbp_last_reply_id":["318519"],"_bbp_last_active_id":["318519"],"_bbp_last_active_time":["2023-11-20 13:57:32"]},"test":"william2-dalleylive-uwe-ac-uk"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/318243","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\/318243\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=318243"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}