Lumped System Connector, Interface (Heat Transfer in Shells Interface)
Use this node to connect the distributed finite element model to a thermal network.
The average temperature on the selected interface can be prescribed at a node of the thermal network where an External Terminal feature of The Lumped Thermal System Interface is applied.
In return, the heat rate defined at the node of the thermal network is applied on the selected interface.
Boundary Selection
Select the boundaries on which to apply the connector.
In addition, select the Restrict to layered boundaries check box to make the node applicable only if a layered material is defined on the boundary. If a layered material (Material with Layer thickness specified, Single Layer Material, Layered Material Link, or Layered Material Stack) is available, its name is then displayed beside the boundary index (for example, slmat1), otherwise the boundary is marked as not applicable.
Note that when the Shell type is Nonlayered shell in the Shells Properties section of the parent interface, the Restrict to layered boundaries check box is not editable.
Interface Selection
Set the interfaces for which the connector should be applied. These can be the top and bottom surfaces of the layered material.
Different settings are available, depending on the settings in the Shell Properties section of the parent interface:
When the Shell type is Layered shell in the Shells Properties section of the parent interface, the available options in the Apply to list are Top interface, Bottom interface, Exterior interfaces, and Selected interfaces. With the last option you can select the interfaces for a given layered material, by clearing the check boxes corresponding to layer interfaces where the node should not be applied in the Selection table. The top and bottom interfaces refer respectively to the upside and downside of the boundary, defined from the orientation of the normal vector. See Interface Selections for more details on the interfaces identification.
When the Shell type is Nonlayered shell in the Shells Properties section of the parent interface, a single layer material is defined on the boundary, and the available options in the Apply to list are Top interface, Bottom interface, and All interfaces.
You can visualize the selected interfaces by clicking the Layer Cross Section Preview and Layer 3D Preview buttons.
Upside and downside settings can be visualized by plotting the global normal vector (nx, ny, nz), that always points from downside to upside. Note that the normal vector (ht.nx, ht.ny, ht.nz) may be oriented differently.
See Tangent and Normal Variables in the COMSOL Multiphysics Reference Manual.
Terminal Inputs
Select an External Terminal feature in the Source list to define which node of the thermal network provides the heat rate Pext to be prescribed on the interface.
When the Isothermal terminal check box is not selected (default), the average temperature on the interface is constrained to the temperature at the terminal node of the thermal network. Select this check box to apply the constraint on the space-dependent temperature instead, which corresponds to a stronger constraint.
Lumped Composite Thermal Barrier with Shells: Application Library path Heat_Transfer_Module/Tutorials,_Thin_Structure/lumped_composite_thermal_barrier_shells
Location in User Interface
Context Menus
Ribbon
Physics tab with Heat Transfer in Shells selected in the model tree: