{"id":34773,"date":"2019-04-17T04:16:18","date_gmt":"2019-04-17T04:16:18","guid":{"rendered":"\/forum\/forums\/topic\/friction-pressure-calculated-by-ktgf\/"},"modified":"2019-04-17T04:16:18","modified_gmt":"2019-04-17T04:16:18","slug":"friction-pressure-calculated-by-ktgf","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/friction-pressure-calculated-by-ktgf\/","title":{"rendered":"Friction pressure calculated by KTGF"},"content":{"rendered":"

Dear all,<\/p>\n

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I’m simulating a multiphase flow using Fluent (version 17.1) with air and a granular phase (TFM approach). I already set the physical parameters of the phases, as well as the boundary conditions, and the simulations are converging well.<\/p>\n

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Now, I want to evaluate the difference in the results when changing the value of the Friction Packing Limit (αs,min<\/span>) of the granular phase, using the frictional pressure calculated based on 1) the KTGF, and on 2) the Johnson and Jackson model. <\/p>\n

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From the Fluent Guide, I can clearly see the expressions for Pfriction and μs,fric<\/span> that are used in the Johnson and Jackson model to account for the frictional stress (shown bellow).<\/p>\n

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\"Johnson<\/p>\n

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Unfortunately, I can not understand which expressions are being used to calculate the frictional stress using the KTGF, as the only information given in the guide is “based-ktgf, where the frictional pressure is defined by the kinetic theory.”, which is too vague for my understanding.<\/p>\n

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* Could you please explain which expressions are used to calculate Pfriction and μfric <\/span>when using the KTGF approach?<\/p>\n

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* Are the KTGF expresions dependent on the Friction Packing Limit (αs,min<\/span>) in the same way as in Johnson and Jackson model? <\/p>\n

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Thank you in advance!<\/p>\n

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 <\/p>\n","protected":false},"template":"","class_list":["post-34773","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_old_topic_id":["6945"],"_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","0"],"_btv_view_count":["992"],"_bbp_subscription":["239853"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["34773"],"_bbp_forum_id":["27792"],"_bbp_engagement":["22555","164597"],"_bbp_voice_count":["2"],"_bbp_reply_count":["6"],"_bbp_last_reply_id":["83345"],"_bbp_last_active_id":["83345"],"_bbp_last_active_time":["2019-04-19 09:07:10"]},"test":"lucasmassarosousa"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/34773","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\/34773\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=34773"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}