{"id":395467,"date":"2024-11-27T05:26:22","date_gmt":"2024-11-27T05:26:22","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/temperature-dependent-viscosity-model-used-in-fluent-flow-analysis\/"},"modified":"2024-11-27T05:26:22","modified_gmt":"2024-11-27T05:26:22","slug":"temperature-dependent-viscosity-model-used-in-fluent-flow-analysis","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/temperature-dependent-viscosity-model-used-in-fluent-flow-analysis\/","title":{"rendered":"Temperature-dependent viscosity model used in FLUENT flow analysis"},"content":{"rendered":"<p>&lt;p&gt;&lt;span class=&#8221;ryNqvb&#8221;&gt;I am using FLUENT to perform flow analysis, but I would like to know about the viscosity equation.&lt;\/span&gt;&lt;span class=&#8221;ryNqvb&#8221;&gt; When fitting the viscosity equation using POLYDATA with viscosity measurements obtained by changing the extrusion temperature of a polymer, I selected the Arrhenius temperature-dependent equation for temperature dependence, and the CROSS model for the viscosity equation.&lt;\/span&gt; &lt;span class=&#8221;ryNqvb&#8221;&gt;I performed a flow analysis, but the inlet pressure became abnormally high, and I think the viscosity equation is suspicious.&lt;\/span&gt; &lt;span class=&#8221;ryNqvb&#8221;&gt;The viscosity equation and temperature-dependent equation in the FLUENT user guide do not match those of POLYDATA.&lt;\/span&gt; &lt;span class=&#8221;ryNqvb&#8221;&gt;In particular, the power law exponent n is a single parameter in the POLYDATA CROSS model, which is (1-n), but in the FLUENT CROSS model, the power of the multiplication of shear rate and &lambda; is 1-n, which is different.&lt;\/span&gt; &lt;span class=&#8221;ryNqvb&#8221;&gt;Please tell me which viscosity equation is used for calculations in actual flow analysis.&lt;\/span&gt;<img decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/11\/27-11-2024-1732685168-viscosity equation.jpg\" alt=\"\" \/>&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-395467","topic","type-topic","status-publish","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_forum_id":["27815"],"_bbp_topic_id":["395467"],"_bbp_subscription":["486238","199"],"_bbp_author_ip":["165.85.159.51"],"_bbp_reply_count":["3"],"_bbp_reply_count_hidden":["0"],"_bbp_voice_count":["2"],"_bbp_engagement":["486238","199"],"_btv_view_count":["993"],"_bbp_topic_status":["unanswered"],"_bbp_last_reply_id":["395637"],"_bbp_last_active_id":["395637"],"_bbp_last_active_time":["2024-11-28 10:25:46"]},"test":"isao-tsujimurakaneka-co-jp"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/395467","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\/395467\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=395467"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}