{"id":393115,"date":"2024-11-07T08:35:00","date_gmt":"2024-11-07T08:35:00","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/cht-simulation-poor-convection-to-one-phase-using-vof-modell\/"},"modified":"2024-11-07T08:35:00","modified_gmt":"2024-11-07T08:35:00","slug":"cht-simulation-poor-convection-to-one-phase-using-vof-modell","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/cht-simulation-poor-convection-to-one-phase-using-vof-modell\/","title":{"rendered":"CHT Simulation: Poor Convection to One Phase using VOF-Modell"},"content":{"rendered":"

<div class=”flex-shrink-0 flex flex-col relative items-end”><div><div class=”pt-0″><div class=”gizmo-bot-avatar flex h-8 w-8 items-center justify-center overflow-hidden rounded-full”><div class=”relative p-1 rounded-sm flex items-center justify-center bg-token-main-surface-primary text-token-text-primary h-8 w-8″> <\/div><\/div><\/div><\/div><\/div><div class=”group\/conversation-turn relative flex w-full min-w-0 flex-col agent-turn”><div class=”flex-col gap-1 md:gap-3″><div class=”flex max-w-full flex-col flex-grow”><div class=”min-h-8 text-message flex w-full flex-col items-end gap-2 whitespace-normal break-words [.text-message+&]:mt-5″ dir=”auto” data-message-author-role=”assistant” data-message-id=”b0fd94c2-571e-4e1b-81da-ba4f5b777fcb” data-message-model-slug=”gpt-4o”><div class=”flex w-full flex-col gap-1 empty:hidden first:pt-[3px]”><div class=”markdown prose w-full break-words dark:prose-invert light”><p>Hello everyone,<\/p><p>In my simulation using the VOF model combined with a CHT method, I have defined oil and air as fluid media, with a constant surface tension coefficient of 0.027 N\/m. Both air and oil share an interface with the housing. The boundary condition on the exterior of the housing is set for convection to the air at 5 W\/m²·K and 22°C. Additionally, I have defined certain internal surfaces as heat sources by specifying a wall thickness and a volumetric heat flux (coupled).<\/p><p>While the pressure, temperature, and velocity results yield a converged solution, I am encountering an issue with heat transfer to the oil. The oil temperature remains close to its initial value throughout the simulation. In contrast, the convection to the air appears to be effective (as shown in the attached image). Interaction between the oil and air is evident, with air bubbles within the oil displaying a higher temperature, but the overall temperature of the oil stays nearly constant.<\/p><p>What could be the reason for this behavior? Any insights or suggestions would be greatly appreciated. Thank you for your help.<br><br><br><br><br><\/p><\/div><\/div><\/div><\/div><\/div><\/div><\/p>\n","protected":false},"template":"","class_list":["post-393115","topic","type-topic","status-publish","hentry","topic-tag-fluent-ansys-1","topic-tag-cht","topic-tag-ImplicitVOF-1"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_subscription":["18929","199"],"_bbp_author_ip":["2001:638:208:fd49:6b:3dff:fecd:d665"],"_btv_view_count":["120"],"_bbp_topic_status":["unanswered"],"_bbp_notification_enabled":["18929"],"_bbp_topic_id":["393115"],"_bbp_forum_id":["27792"],"_bbp_engagement":["199","18929"],"_bbp_voice_count":["2"],"_bbp_reply_count":["1"],"_bbp_last_reply_id":["393214"],"_bbp_last_active_id":["393214"],"_bbp_last_active_time":["2024-11-07 15:51:04"]},"test":"fyoussefrhrk-uni-kl-de"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/393115","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\/393115\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=393115"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}