{"id":397547,"date":"2024-12-16T04:32:29","date_gmt":"2024-12-16T04:32:29","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/heat-transfer-flux-vs-volume-integral-udf-energy-source\/"},"modified":"2024-12-16T04:32:29","modified_gmt":"2024-12-16T04:32:29","slug":"heat-transfer-flux-vs-volume-integral-udf-energy-source","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/heat-transfer-flux-vs-volume-integral-udf-energy-source\/","title":{"rendered":"Heat transfer flux vs volume-integral UDF energy source"},"content":{"rendered":"<p>&lt;p&gt;Hello!&lt;\/p&gt;&lt;p&gt;clarificatoin question: what is the difference between the volume-integral UDF and the heat transfer rate flux? I want to model an arc inside a domain. After separating two zones, I prescribe a UDS energy source term inside the arc. I know the arc should have X amount of energy in Watts. I normally calculate the heat transfer rate in the &#8220;arc&#8221; region to check the amount of energy.&lt;\/p&gt;&lt;p&gt;My understanding is that the heat transfer rate is heat transfer between a surface to the fluid, but would this definition be the same if my &#8220;surface&#8221; is for a fluid region inside my mesh? I&#8217;ve attached examples of the flux reports that I&#8217;m questioning below. Thank you!&lt;\/p&gt;&lt;p&gt;&nbsp;&lt;\/p&gt;&lt;p&gt;<img decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/12\/16-12-2024-1734323529-mceclip1.png\" \/>&nbsp;&lt;\/p&gt;&lt;p&gt;&nbsp;&lt;\/p&gt;&lt;p&gt;<img decoding=\"async\" src=\"https:\/\/innovationspace.ansys.com\/forum\/wp-content\/uploads\/sites\/2\/2024\/12\/16-12-2024-1734323420-mceclip0.png\" \/>&lt;\/p&gt;<\/p>\n","protected":false},"template":"","class_list":["post-397547","topic","type-topic","status-publish","hentry"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 4.9.10 - aioseo.com -->\n\t<meta name=\"description\" content=\"Hello!clarificatoin question: what is the difference between the volume-integral UDF and the heat transfer rate flux? I want to model an arc inside a domain. After separating two zones, I prescribe a UDS energy source term inside the arc. I know the arc should have X amount of energy in Watts. I normally calculate the\" \/>\n\t<meta name=\"robots\" content=\"max-image-preview:large\" \/>\n\t<link rel=\"canonical\" href=\"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/heat-transfer-flux-vs-volume-integral-udf-energy-source\/\" \/>\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 Learning Forum | Ansys Innovation Space\" \/>\n\t\t<meta property=\"og:type\" content=\"article\" \/>\n\t\t<meta property=\"og:title\" content=\"Heat transfer flux vs volume-integral UDF energy source | Ansys Learning Forum\" \/>\n\t\t<meta property=\"og:description\" content=\"Hello!clarificatoin question: what is the difference between the volume-integral UDF and the heat transfer rate flux? I want to model an arc inside a domain. After separating two zones, I prescribe a UDS energy source term inside the arc. I know the arc should have X amount of energy in Watts. I normally calculate the\" \/>\n\t\t<meta property=\"og:url\" content=\"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/heat-transfer-flux-vs-volume-integral-udf-energy-source\/\" \/>\n\t\t<meta property=\"article:published_time\" content=\"2024-12-16T04:32:29+00:00\" \/>\n\t\t<meta property=\"article:modified_time\" content=\"2024-12-16T04:32:29+00:00\" \/>\n\t\t<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n\t\t<meta name=\"twitter:title\" content=\"Heat transfer flux vs volume-integral UDF energy source | Ansys Learning Forum\" \/>\n\t\t<meta name=\"twitter:description\" content=\"Hello!clarificatoin question: what is the difference between the volume-integral UDF and the heat transfer rate flux? I want to model an arc inside a domain. After separating two zones, I prescribe a UDS energy source term inside the arc. I know the arc should have X amount of energy in Watts. 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