{"id":451436,"date":"2026-01-28T11:55:52","date_gmt":"2026-01-28T11:55:52","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/energy-source-term-formulation-for-multi-component-condensation\/"},"modified":"2026-01-28T11:55:52","modified_gmt":"2026-01-28T11:55:52","slug":"energy-source-term-formulation-for-multi-component-condensation","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/energy-source-term-formulation-for-multi-component-condensation\/","title":{"rendered":"Energy Source Term formulation for multi-component condensation"},"content":{"rendered":"<p>&lt;p&gt;Hello everyone\uff01&lt;\/p&gt;&lt;p&gt;&nbsp;I am using the <strong>species transport<\/strong> model along with <strong>source term UDFs<\/strong> to solve a <strong>condensation phase change problem<\/strong> in a gas mixture. The mixture consists of <strong>water vapor and some non-condensable gases<\/strong> (carbon dioxide, nitrogen, etc.), where only the water vapor component can condense. Since condensation involves simultaneous heat and mass transfer, the condensation of water vapor produces liquid water, consuming the water vapor component in the gas phase and <strong>releasing latent heat<\/strong>. My current question is about the expression for the energy source term: in the expression where the latent heat of water is subtracted by the kinetic energy, should we then subtract the static enthalpy of the <strong>gas mixture or the static enthalpy of the water vapor component<\/strong>?&lt;\/p&gt;&lt;p&gt;Thank you for your time and consideration. Any insights would be greatly appreciated.&lt;\/p&gt;&lt;p&gt;<img decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2026\/01\/28-01-2026-1769601185-mceclip0.png\" \/>&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-451436","topic","type-topic","status-publish","hentry","topic-tag-condensation","topic-tag-define-source","topic-tag-fluent","topic-tag-multi-species-1"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_forum_id":["291848"],"_bbp_topic_id":["451436"],"_bbp_subscription":["526202","199"],"_bbp_author_ip":["23.177.40.85"],"_bbp_last_reply_id":["451450"],"_bbp_last_active_id":["451450"],"_bbp_last_active_time":["2026-01-28 13:16:43"],"_bbp_reply_count":["1"],"_bbp_reply_count_hidden":["0"],"_bbp_voice_count":["2"],"_bbp_engagement":["526202","199"],"_btv_view_count":["175"],"_bbp_topic_status":["unanswered"]},"test":"james411projectgmail-com"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/451436","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\/451436\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=451436"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}