{"id":240762,"date":"2022-11-15T04:48:49","date_gmt":"2022-11-15T04:48:49","guid":{"rendered":"\/forum\/forums\/topic\/drag-coefficient-3\/"},"modified":"2022-11-15T04:48:49","modified_gmt":"2022-11-15T04:48:49","slug":"drag-coefficient-3","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/drag-coefficient-3\/","title":{"rendered":"Drag coefficient"},"content":{"rendered":"<p>hi all, ti try to use fluent, so i&#8217;ve tried to simulate flow fluid around a 2mm ball inside a 1 liter fluid box (100x100x100 mm)<\/p>\n<p><img decoding=\"async\" src=\"\/forum\/wp-content\/uploads\/sites\/2\/2022\/11\/15-11-2022-1668486715-2mm ball.png\" alt=\"\"><\/p>\n<p>ball is the ridiculous sized point at the center of the french flag<\/p>\n<p>&nbsp;<\/p>\n<p>so&#8230; from <a href=\"https:\/\/www.researchgate.net\/figure\/Drag-Coefficient-versus-Velocity-of-Sphere-with-different-surface-roughness_fig4_344361797\" target=\"_blank\" rel=\"noopener\">here <\/a>we can saw :&nbsp;<\/p>\n<p>Cd of a smooth sphere around 0.47 at 5m\/s and around 0.08 at 30m\/s (see graph)<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/www.researchgate.net\/profile\/Sai-Ganesh-Sabbavarapu\/publication\/344361797\/figure\/fig4\/AS:939200518029313@1600934261219\/Drag-Coefficient-versus-Velocity-of-Sphere-with-different-surface-roughness.png\" alt=\"\"><\/p>\n<p>i&#8217;ve made a coefficient drag report file with it&#8217;s plot with Y force Vector set to 1.<\/p>\n<p>and the computation zone setted to my ball mesh<\/p>\n<p>&nbsp;<\/p>\n<p>anyway i&#8217;m not able to find these values, and furthermore i got plethore amout of value dependant of intialisation caract&eacute;ristic like hybrid\/standard or pressure\/density based&#8230; etc&#8230;<\/p>\n<p>&nbsp;<\/p>\n<p>so what can i do to get repeatability, accuracy and &#8220;good&#8221; value with my simulation ?<\/p>\n","protected":false},"template":"","class_list":["post-240762","topic","type-topic","status-closed","hentry","topic-tag-computational-fluid","topic-tag-drag-coefficient","topic-tag-fluid","topic-tag-fluid-domain-1","topic-tag-initialization","topic-tag-solver-initialization-1"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["267743","16400","218","199"],"_bbp_author_ip":["23.220.96.180"]," _bbp_last_reply_id":["0"]," _bbp_likes_count":["0"],"_btv_view_count":["5503"],"_edit_lock":["1668502694:142249"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["240762"],"_bbp_forum_id":["27792"],"_bbp_engagement":["199","218","267743"],"_bbp_voice_count":["3"],"_bbp_reply_count":["37"],"_bbp_last_reply_id":["242365"],"_bbp_last_active_id":["242365"],"_bbp_last_active_time":["2022-11-29 16:21:15"]},"test":"charles-webhotmail-fr"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/240762","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\/240762\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=240762"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}