{"id":161639,"date":"2023-01-25T07:16:34","date_gmt":"2023-01-25T07:16:34","guid":{"rendered":"\/knowledge\/forums\/topic\/which-uds-boundary-condition-does-the-fluent-solver-use-for-interior-zones\/"},"modified":"2023-07-31T12:35:38","modified_gmt":"2023-07-31T12:35:38","slug":"which-uds-boundary-condition-does-the-fluent-solver-use-for-interior-zones","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/which-uds-boundary-condition-does-the-fluent-solver-use-for-interior-zones\/","title":{"rendered":"Which UDS boundary condition does the Fluent solver use for interior zones?"},"content":{"rendered":"<p>Question: a Fluent model consists of several connected cell zones. The UDS (user-defined scalar) equation is activated only for one of them. Correspondingly, the solution domain for the UDS equation will have boundary zones from type interior. For these boundary type, no UDS boundary condition can be defined by the user. Which boundary condition type is used from the Fluent solver for this boundary by default?  Answer: The solver will use flux=0 as the boundary condition for the interior face if uds is not solved in one side of the zone.<\/p>\n","protected":false},"template":"","class_list":["post-161639","topic","type-topic","status-publish","hentry","topic-tag-17-2","topic-tag-fluent","topic-tag-fluid-dynamics","topic-tag-general","topic-tag-general-fluent"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 4.9.10 - aioseo.com -->\n\t<meta name=\"description\" content=\"Question: a Fluent model consists of several connected cell zones. The UDS (user-defined scalar) equation is activated only for one of them. Correspondingly, the solution domain for the UDS equation will have boundary zones from type interior. For these boundary type, no UDS boundary condition can be defined by the user. 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