{"id":391728,"date":"2024-10-29T12:35:45","date_gmt":"2024-10-29T12:35:45","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/cht-simulation-using-vof-model-steady-state\/"},"modified":"2024-10-29T12:35:45","modified_gmt":"2024-10-29T12:35:45","slug":"cht-simulation-using-vof-model-steady-state","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/cht-simulation-using-vof-model-steady-state\/","title":{"rendered":"CHT Simulation Using VOF Model (Steady-State)"},"content":{"rendered":"<p>&lt;p&gt;Hello,&lt;\/p&gt;&lt;p&gt;I&#8217;m simulating fluid flow within a gearbox using Fluent. I have set up a Volume of Fluid (VOF) model comprising two phases: oil and air. The interface tension is constant at 0.027 N\/m. I&rsquo;m accounting for body forces in an implicit model and considering wall adhesion with a sharp\/dispersed configuration. Additionally, I&#8217;ve defined rotating walls and included a heat source in the system.&lt;\/p&gt;&lt;p&gt;Using the SST &lt;span class=&#8221;katex&#8221;&gt;&lt;span class=&#8221;katex-mathml&#8221;&gt;k-&omega;k\\text{-}\\omega&lt;\/span&gt;&lt;span class=&#8221;katex-html&#8221; aria-hidden=&#8221;true&#8221;&gt;&lt;span class=&#8221;base&#8221;&gt;&lt;span class=&#8221;mord mathnormal&#8221;&gt;k&lt;\/span&gt;&lt;span class=&#8221;mord text&#8221;&gt;&lt;span class=&#8221;mord&#8221;&gt;-&lt;\/span&gt;&lt;\/span&gt;&lt;span class=&#8221;mord mathnormal&#8221;&gt;&omega;&lt;\/span&gt;&lt;\/span&gt;&lt;\/span&gt;&lt;\/span&gt; turbulence model, the flow converges well, with a &lt;span class=&#8221;katex&#8221;&gt;&lt;span class=&#8221;katex-mathml&#8221;&gt;y+y^+&lt;\/span&gt;&lt;span class=&#8221;katex-html&#8221; aria-hidden=&#8221;true&#8221;&gt;&lt;span class=&#8221;base&#8221;&gt;&lt;span class=&#8221;mord&#8221;&gt;&lt;span class=&#8221;mord mathnormal&#8221;&gt;y&lt;\/span&gt;&lt;span class=&#8221;msupsub&#8221;&gt;&lt;span class=&#8221;vlist-t&#8221;&gt;&lt;span class=&#8221;vlist-r&#8221;&gt;&lt;span class=&#8221;vlist&#8221;&gt;&lt;span class=&#8221;sizing reset-size6 size3 mtight&#8221;&gt;&lt;span class=&#8221;mbin mtight&#8221;&gt;+&lt;\/span&gt;&lt;\/span&gt;&lt;\/span&gt;&lt;\/span&gt;&lt;\/span&gt;&lt;\/span&gt;&lt;\/span&gt;&lt;\/span&gt;&lt;\/span&gt;&lt;\/span&gt; value under 5. I&#8217;ve also specified the oil viscosity as a function of temperature using an expression and assumed the air density to be that of an ideal, incompressible fluid. However, I&rsquo;m not observing any significant convective heat transfer to the oil.&lt;\/p&gt;&lt;p&gt;When I change the density from constant to temperature-dependent or assume the oil is an incompressible ideal fluid, the results seem counterintuitive. I don&#8217;t understand how this adjustment affects the thermal conductivity of the oil, which I&rsquo;ve set as constant.&lt;\/p&gt;&lt;p&gt;Could you please offer any tips on improving the convective heat transfer to the oil in this simulation?&lt;\/p&gt;&lt;p&gt;Best regards,&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-391728","topic","type-topic","status-publish","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["18929","199"],"_bbp_author_ip":["2001:638:208:fd49:6b:3dff:fecd:d665"],"_btv_view_count":["320"],"_bbp_topic_status":["unanswered"],"_bbp_notification_enabled":["18929"],"_edit_lock":["1730205488:18929"],"_bbp_topic_id":["391728"],"_bbp_forum_id":["27792"],"_bbp_engagement":["199","18929"],"_bbp_voice_count":["2"],"_bbp_reply_count":["14"],"_bbp_last_reply_id":["391968"],"_bbp_last_active_id":["391968"],"_bbp_last_active_time":["2024-10-30 11:14:45"]},"test":"fyoussefrhrk-uni-kl-de"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/391728","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\/391728\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=391728"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}