{"id":166133,"date":"2023-03-17T13:11:07","date_gmt":"2023-03-17T13:11:07","guid":{"rendered":"\/knowledge\/forums\/topic\/setting-operating-density-for-natural-convection-cases-when-density-is-modelled-using-ideal-gas-law\/"},"modified":"2023-07-31T12:27:22","modified_gmt":"2023-07-31T12:27:22","slug":"setting-operating-density-for-natural-convection-cases-when-density-is-modelled-using-ideal-gas-law","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/setting-operating-density-for-natural-convection-cases-when-density-is-modelled-using-ideal-gas-law\/","title":{"rendered":"Setting Operating Density for Natural Convection cases when density is modelled using Ideal gas law"},"content":{"rendered":"<p>In ANSYS Fluent, when density is modelled using ideal gas law, it is recommended to use an operating density value of zero. In such cases, users need to be careful in setting up boundary conditions for pressure outlets\/inlets. In natural convection cases, where minor density differences (due to temperature variations) cause the flow, choosing the right operating density would be important for good convergence. This documents provides guidelines in choosing the best operating density values for such cases using an example.<\/p>\n<p>Attachments:<br \/>\n1. <a href=https:\/\/ansys13.ansys.com\/KnowledgeArticles\/Phase-1\/2041750\/2041750_Corrected.pdf>2041750_Corrected.pdf<\/a><\/p>\n","protected":false},"template":"","class_list":["post-166133","topic","type-topic","status-publish","hentry","topic-tag-4431","topic-tag-fluent","topic-tag-fluid-dynamics","topic-tag-heat-transfer-and-radiation","topic-tag-heat-transfer","topic-tag-modeling-setup-advice","topic-tag-natural-convection"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 4.9.10 - aioseo.com -->\n\t<meta name=\"description\" content=\"In ANSYS Fluent, when density is modelled using ideal gas law, it is recommended to use an operating density value of zero. In such cases, users need to be careful in setting up boundary conditions for pressure outlets\/inlets. In natural convection cases, where minor density differences (due to temperature variations) cause the flow, choosing the\" \/>\n\t<meta name=\"robots\" content=\"max-image-preview:large\" \/>\n\t<link rel=\"canonical\" href=\"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/setting-operating-density-for-natural-convection-cases-when-density-is-modelled-using-ideal-gas-law\/\" \/>\n\t<meta name=\"generator\" content=\"All in One SEO (AIOSEO) 4.9.10\" \/>\n\t\t<meta property=\"og:locale\" content=\"en_US\" \/>\n\t\t<meta property=\"og:site_name\" content=\"Ansys Knowledge | Ansys Innovation Space\" \/>\n\t\t<meta property=\"og:type\" content=\"article\" \/>\n\t\t<meta property=\"og:title\" content=\"Setting Operating Density for Natural Convection cases when density is modelled using Ideal gas law | Ansys Knowledge\" \/>\n\t\t<meta property=\"og:description\" content=\"In ANSYS Fluent, when density is modelled using ideal gas law, it is recommended to use an operating density value of zero. 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In natural convection cases, where minor density differences (due to temperature variations) cause the flow, choosing the\" \/>\n\t\t<meta property=\"og:url\" content=\"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/setting-operating-density-for-natural-convection-cases-when-density-is-modelled-using-ideal-gas-law\/\" \/>\n\t\t<meta property=\"article:published_time\" content=\"2023-03-17T13:11:07+00:00\" \/>\n\t\t<meta property=\"article:modified_time\" content=\"2023-07-31T12:27:22+00:00\" \/>\n\t\t<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n\t\t<meta name=\"twitter:title\" content=\"Setting Operating Density for Natural Convection cases when density is modelled using Ideal gas law | Ansys Knowledge\" \/>\n\t\t<meta name=\"twitter:description\" content=\"In ANSYS Fluent, when density is modelled using ideal gas law, it is recommended to use an operating density value of zero. In such cases, users need to be careful in setting up boundary conditions for pressure outlets\/inlets. 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