Thermal Insulation (Thin Layer, Thin Film, Fracture, and Heat Transfer in Shells Interface)

Thisnode is the default edge condition on shells. This condition means that there is no heat flux across the edge:

and hence specifies where the shell is insulated. In most cases, the heat flux q is defined from the Fourier’s law, and this condition sets the temperature gradient to zero across the edge. As the default boundary condition, this feature is applicable only on external edges; but when added manually, it can be applied on interior edges as well.

At internal edges corresponding to the junction of shells of different layered materials, the continuity of the temperature field across the edge depends on the in the , or parent feature (Heat Transfer interface), or in the , or feature (Heat Transfer in Shells interface):

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When the is thermal insulation is implicitly applied, and the temperature field is discontinuous across the edge. This default behavior can be modified by using the Shell Continuity (Heat Transfer Interface) and Continuity (Heat Transfer in Shells Interface) feature on the edge.

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When the is , continuity of the temperature field is implicitly applied.

Edge Selection

Select the edges on which to apply a no flux condition. The check box makes the node applicable only if a layered material is defined on the edge. If a layered material ( with specified, , , or ) is available, its name is then displayed beside the edge index (for example, slmat1), otherwise the edge is marked as not applicable.

Note that when the is in the section of the parent interface or node, the check box is not editable.

In addition, in 2D, edges are modeled as points and this section is named , containing a check box.

Shell Properties

This section is available only when the is in the section of the parent interface or node. You can limit the contribution to individually selected layers by clearing the check box. For a given or , you get access to a list of check boxes for the selection of the individual layers.


	When the Layer type is Thermally thin approximation, and the shell is adjacent to domains where the temperature field is continuous, applying a thermal insulation on such a thermally thin edge has no effect.


	The desired selection for the node may correspond to boundaries with different layered materials. See Layered Material, Layered Material Link, Layered Material Stack, Layered Material Link (Subnode), and Single-Layer Materials in the COMSOL Multiphysics Reference Manual.


	Theory for Heat Transfer in Thin Structures


	Shell Conduction: Application Library path Heat_Transfer_Module/Tutorials,_Thin_Structure/shell_conduction

Location in User Interface

Context Menus

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Physics Tab with selected in the model tree:

Physics Tab with selected: