Thermal Insulation
This node is the default boundary condition for all Heat Transfer interfaces. This boundary condition means that there is no heat flux across the boundary:
and hence specifies where the domain is well insulated. Intuitively, this equation says that the temperature gradient across the boundary is zero. For this to be true, the temperature on one side of the boundary must equal the temperature on the other side. Because there is no temperature difference across the boundary, heat cannot transfer across it. As the default boundary condition, it can be applied only on external boundaries; but when added manually, it can be applied also on internal boundaries.
Location in User Interface
Context menus
 Heat Transfer>Thermal Insulation
Heat Transfer in Solids>Thermal Insulation
Heat Transfer in Fluids>Thermal Insulation
Heat Transfer in Porous Media>Thermal Insulation
Bioheat Transfer>Thermal Insulation
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 or Bioheat Transfer selected:
Boundaries>interface>Thermal Insulation