{"id":170783,"date":"2023-06-05T07:05:07","date_gmt":"2023-06-05T07:05:07","guid":{"rendered":"\/knowledge\/forums\/topic\/how-mechanical-mapdl-uses-tref-and-tunif-to-identify-the-temperature-to-be-used-to-define-material-properties\/"},"modified":"2023-07-31T12:33:45","modified_gmt":"2023-07-31T12:33:45","slug":"how-mechanical-mapdl-uses-tref-and-tunif-to-identify-the-temperature-to-be-used-to-define-material-properties","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/how-mechanical-mapdl-uses-tref-and-tunif-to-identify-the-temperature-to-be-used-to-define-material-properties\/","title":{"rendered":"How Mechanical\/MAPDL uses TREF and TUNIF to identify the temperature to be used to define material properties?"},"content":{"rendered":"<p>If one does not not have a coefficient of thermal expansion (alpha) defined, then the Environment Temperature (TREF command in MAPDL) should not affect the results.  That temperature is only used to calculate the thermal strains based on the difference between it and the nodal temperatures (alpha* deltaT).  If alpha is zero, the calculated thermal strains are zero, regardless of the TREF setting.  Nodal temperatures are calculated from a thermal analysis or imposed by a thermal condition (TUNIF command in MAPDL).  If temperature dependent material properties are defined, the nodal temperature are used by the solver to identify the correct material properties.  If material properties are only defined for one temperature, then the solver will use those properties regardless of the nodal temperatures.  Reference Temperature is the temperature at which the model experiences zero strain.  It is only used to calculate the thermal strains.  It does affect the material properties used by the solver.<\/p>\n","protected":false},"template":"","class_list":["post-170783","topic","type-topic","status-publish","hentry","topic-tag-18-1","topic-tag-general","topic-tag-materials","topic-tag-mechanical","topic-tag-structural-mechanics","topic-tag-thermal"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 4.9.10 - aioseo.com -->\n\t<meta name=\"description\" content=\"If one does not not have a coefficient of thermal expansion (alpha) defined, then the Environment Temperature (TREF command in MAPDL) should not affect the results. That temperature is only used to calculate the thermal strains based on the difference between it and the nodal temperatures (alpha* deltaT). If alpha is zero, the calculated thermal\" \/>\n\t<meta name=\"robots\" content=\"max-image-preview:large\" \/>\n\t<link rel=\"canonical\" href=\"https:\/\/innovationspace.ansys.com\/knowledge\/forums\/topic\/how-mechanical-mapdl-uses-tref-and-tunif-to-identify-the-temperature-to-be-used-to-define-material-properties\/\" \/>\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=\"How Mechanical\/MAPDL uses TREF and TUNIF to identify the temperature to be used to define material properties? | Ansys Knowledge\" \/>\n\t\t<meta property=\"og:description\" content=\"If one does not not have a coefficient of thermal expansion (alpha) defined, then the Environment Temperature (TREF command in MAPDL) should not affect the results. 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