{"id":38565,"date":"2019-10-25T19:25:00","date_gmt":"2019-10-25T19:25:00","guid":{"rendered":"\/forum\/forums\/topic\/mismatch-in-fluent-calculation-of-drag-coefficient\/"},"modified":"2019-10-25T19:25:00","modified_gmt":"2019-10-25T19:25:00","slug":"mismatch-in-fluent-calculation-of-drag-coefficient","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/mismatch-in-fluent-calculation-of-drag-coefficient\/","title":{"rendered":"Mismatch in FLUENT calculation of Drag coefficient"},"content":{"rendered":"<p>Hey all,<\/p>\n<p><\/p>\n<p>I have&nbsp;the drag\/lift results of simulating a&nbsp;pitching airfoil for which the FLUENT gives me negative drag!<\/p>\n<p><\/p>\n<p>I set pitching motion to the whole domain by UDF in Dynamic mesh. The incoming velocity is also a function of time. However, I am getting negative Cd at a portion of the simulation which does not make sense.&nbsp;<br \/>I calculated Cd by using Pressure values on airfoil nodes and got a different number from FLUENT.<\/p>\n<p><\/p>\n<p>Any of you have seen this discrepancy before? Do you have any idea why Cd is negative?<\/p>\n<p><\/p>\n<p>&nbsp;<\/p>\n<p><\/p>\n<p>I really appreciate any help,<\/p>\n<p><\/p>\n<p>Omid<\/p>\n","protected":false},"template":"","class_list":["post-38565","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_old_topic_id":["10743"],"_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":["4377"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["38565"],"_bbp_forum_id":["27792"],"_bbp_engagement":["199","22555","158097"],"_bbp_voice_count":["3"],"_bbp_reply_count":["25"],"_bbp_last_reply_id":["97951"],"_bbp_last_active_id":["97951"],"_bbp_last_active_time":["2019-11-06 11:51:46"]},"test":"omid1988"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/38565","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\/38565\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=38565"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}