{"id":450871,"date":"2026-01-21T09:29:02","date_gmt":"2026-01-21T09:29:02","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/negative-droplet-growth-rate-in-fluent-wet-steam-model\/"},"modified":"2026-01-21T09:29:02","modified_gmt":"2026-01-21T09:29:02","slug":"negative-droplet-growth-rate-in-fluent-wet-steam-model","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/negative-droplet-growth-rate-in-fluent-wet-steam-model\/","title":{"rendered":"Negative droplet growth rate in Fluent wet steam model"},"content":{"rendered":"<p>&lt;p data-path-to-node=&#8221;3,0&#8243;&gt;Hello everyone!&lt;\/p&gt;&lt;p data-path-to-node=&#8221;3,1&#8243;&gt;I am currently using the &lt;strong data-path-to-node=&#8221;3,1&#8243; data-index-in-node=&#8221;25&#8243;&gt;Wet Steam Model<\/strong> in ANSYS Fluent. In this model, the <strong>mass source term<\/strong> for the vapor phase is defined by two components: <strong>droplet nucleation and droplet growth<\/strong>, as shown in the equations below:&lt;\/p&gt;&lt;p data-path-to-node=&#8221;3,2&#8243;&gt;<img decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2026\/01\/21-01-2026-1768987511-mceclip0.png\" \/><img decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2026\/01\/21-01-2026-1768987527-mceclip1.png\" \/><img decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2026\/01\/21-01-2026-1768987538-mceclip2.png\" \/>&lt;\/p&gt;&lt;p data-path-to-node=&#8221;3,3&#8243;&gt;Based on my research into non-equilibrium condensation flows, both <strong>droplet condensation (growth) and evaporation<\/strong> should occur. This implies that the droplet growth rate can be <strong>either positive or negative<\/strong>.&lt;\/p&gt;&lt;p data-path-to-node=&#8221;3,4&#8243;&gt;However, according to the definitions provided in the Fluent documentation, it appears that the droplet growth term is treated as positive only. I am curious: &lt;strong data-path-to-node=&#8221;3,4&#8243; data-index-in-node=&#8221;159&#8243;&gt;How does the Wet Steam Model account for the droplet evaporation process?<\/strong>&lt;\/p&gt;&lt;p data-path-to-node=&#8221;3,4&#8243;&gt;Thanks for any insights you can provide.&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-450871","topic","type-topic","status-publish","hentry","topic-tag-multiphase_models-1","topic-tag-fluent","topic-tag-wet-steam"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_forum_id":["291848"],"_bbp_topic_id":["450871"],"_bbp_subscription":["526202","199"],"_bbp_author_ip":["45.39.199.149"],"_bbp_last_reply_id":["450909"],"_bbp_last_active_id":["450909"],"_bbp_last_active_time":["2026-01-21 13:24:01"],"_bbp_reply_count":["3"],"_bbp_reply_count_hidden":["0"],"_bbp_voice_count":["2"],"_bbp_engagement":["526202","199"],"_btv_view_count":["183"],"_bbp_topic_status":["unanswered"]},"test":"james411projectgmail-com"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/450871","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\/450871\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=450871"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}