Thin Layer
This node defines the thermal conductivity and thermodynamics properties of a resistive material located on internal or external boundaries. This material can be formed of one or more layers.
When the layer is a bad thermal conductor compared to the adjacent geometry, the tangential heat flux can be neglected and only the heat flux across the layer’s thickness is considered. The layer can be constituted of multiple sublayers with specific thickness and thermal properties. This condition may also be used to enforce consistent initial conditions.
Layer Selection
Select the applicable layers (the default setting is All layered materials) defining the required material properties for the node.
If no layered materials have been included yet, there is a shorthand available for creating a Single Layer Material, a Layered Material Link, or a Layered Material Stack (the plus, next to the Layered Material list).
When a layered material stack or link is selected from the Layered Material list, clear the check boxes corresponding to layers where the node should not be applied in the Selection table.
You can visualize the selected layered materials and layers in each layered material by clicking the Layer Cross Section Preview and Layer 3D Preview buttons.
The desired selection for the node may correspond to boundaries with different layered materials. The All layered materials option allows to gather these materials to make the desired selection applicable for the node on the union of the boundaries where the layered materials are defined.
Model Input
This section has fields and values that are inputs to expressions that define material properties. If such user-defined property groups are added, the model inputs appear here.
Volume reference temperature
This section is available when a temperature-dependent density defined in a material is used. On the material frame, the density is evaluated onto a reference temperature to ensure mass conservation in the presence of temperature variations. By default the Common model input is used. This corresponds to the variable minput.Tempref, which is set by default to 293.15 K. To edit it, click the Go to Source button (), and in the Default Model Inputs node under Global Definitions, set a value for the Volume reference temperature in the Expression for remaining selection section.
The other options are User defined and all temperature variables from the physics interfaces included in the model.
This model input does not override the Reference temperature Tref set in the Physical Model section of the physics interface, and that is used to evaluate the reference enthalpy, and a reference density for incompressible nonisothermal flows.
Temperature
This section is available when temperature-dependent material properties are used. By default the temperature of the parent interface is used and the section is not editable. To edit the Temperature field, click Make All Model Inputs Editable (). The available options are User defined (default), Common model input (the minput.T variable, set to 293.15 K by default), and all temperature variables from the physics interfaces included in the model. To edit the minput.T variable, click the Go to Source button (), and in the Default Model Inputs node under Global Definitions, set a value for the Temperature in the Expression for remaining selection section.
Layer Model
The only option for Layer type is Thermally thick approximation.
From the Specify list select Layer properties (the default) or Thermal resistance, to set either the Thermal conductivity k or the Thermal resistance Rs.
Heat Conduction
The default Thermal conductivity k is taken From layered material. For User defined select Isotropic, Diagonal, Symmetric, or Full to enter another value or expression.
Alternatively, set a value for the Thermal resistance Rs if Specify is set to Thermal resistance in the Layer Model section.
Thermodynamics
By default the Density ρ and Heat capacity at constant pressure Cp of the layer are taken From layered material. For User defined enter other values or expressions. These properties are only used in time-dependent studies, but must be set in all cases.
Location in User Interface
Context menus
Ribbon
Physics Tab with interface as Heat Transfer in Solids, Heat Transfer in Fluids, or Heat Transfer in Solids and Fluids selected: