Isothermal Domain
This node should be used when the temperature shows sufficiently small spatial fluctuations to be considered homogeneous in space but not necessarily in time.
Isothermal Domain
Two options are available for the Temperature definition into the Isothermal Domain:
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If From heat balance (the default) is selected, the temperature is computed as the solution of a reduced form of the heat equation due to spatial homogeneity. See Equation 4-32.
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If From prescribed temperature is selected, the temperature is set to the domain Temperature T0 that needs to be specified. For User defined, enter a value or expression for the Temperature T0. Else, select an Ambient temperature defined in the Ambient Settings section of a Heat Transfer or Heat Transfer in Shells interface.
Thermodynamics
The thermodynamics properties of the Isothermal Domain are set in this section. Two options are available for the Mass definition:
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If Density is selected, the Density ρ should be specified.
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If Total mass is selected, the Mass m should be specified.
Finally the Heat capacity at constant pressure Cp should be specified.
It is not possible to couple an Isothermal Domain with the Laminar Flow interface through the Nonisothermal Flow multiphysics condition.
The following conditions of heat exchange can be applied at isothermal domain interfaces: thermal insulation, continuity, ventilation, convective heat flux, and thermal contact. See Isothermal Domain Interface for more details.
Also see Theory for Lumped Isothermal Domain.
When Surface-to-surface radiation is activated, the Opacity subnode is automatically added to the entire selection, with Transparent option selected. The domain selection can’t be edited. To set some part of the domain as opaque, add a new Opacity subnode from the context menu (right-click the parent node) or from the Physics toolbar, Attributes menu.
Natural Convection Cooling of a Vacuum Flask: Application Library path Heat_Transfer_Module/Tutorials,_Forced_and_Natural_Convection/vacuum_flask
Location in User Interface
Context menus
If the Isothermal domain check box is selected under the Physical Model section:
Heat Transfer>Isothermal Domain
Heat Transfer in Solids>Isothermal Domain
Heat Transfer in Fluids>Isothermal Domain
Heat Transfer in Porous Media>Isothermal Domain
Heat Transfer in Building Materials>Isothermal Domain
Bioheat Transfer>Isothermal Domain
Heat Transfer with Surface-to-Surface Radiation>Isothermal Domain
Heat Transfer with Radiation in Participating Media>Isothermal Domain
Ribbon
Physics Tab with interface as Heat Transfer, Heat Transfer in Solids, Heat Transfer in Fluids, Heat Transfer in Porous Media, Heat Transfer in Building Materials, Bioheat Transfer, Heat Transfer with Surface-to-Surface Radiation or Heat Transfer with Radiation in Participating Media selected:
Domains>interface>Isothermal Domain