Point Heat Source
This node, available for 3D components, models a heat source (or sink) that is so small that it can be considered to have no spatial extension.
In theory, the temperature in a point source in 3D is plus infinity (to compensate for the fact that the heat source does not have a spatial extension). The finite element discretization used in COMSOL Multiphysics returns a finite value, but that value must be interpreted in a weak sense.
Point Heat Source
Enter the Point heat source Qp in unit power. A positive Qp corresponds to heating while a negative Qp corresponds to cooling.
Heat Source Radius
With the Heat Transfer Module, you can model the heat source explicitly and apply it on a ball or disk around the point.
Select the Specify heat source radius check box to define the Heat source radius R. This setting averages the source on a ball or disk of given radius around the point, and avoids obtaining an increasing temperature shift at the point when meshing finer than this radius. It makes use of the ballavg or diskavg operator for averaging around the source.
Frame Selection
This section is not available if the Specify heat source radius option is disabled. The settings are the same as for the Heat Source node and are described under Frame Selection.
See Built-In Operators in the COMSOL Multiphysics Reference Manual for additional information about the ballavg and diskavg operators.
You can specify the source to be a harmonic perturbation in a frequency domain analysis. To mark the source as being a harmonic perturbation, right-click the node and choose Harmonic Perturbation. Note that this updates the node’s icon. See Theory for Harmonic Heat Transfer for more details.
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Handling Frames in Heat Transfer
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About the Heat Transfer Interfaces
Heat Conduction with a Localized Heat Source on a Disk: Application Library path Heat_Transfer_Module/Verification_Examples/localized_heat_source
Location in User Interface
Context menus
Heat Transfer in Solids>Points>Point Heat Source
Heat Transfer in Fluids>Points>Point Heat Source
Heat Transfer in Porous Media>Points>Point Heat Source
Bioheat Transfer>Points>Point Heat Source
Heat Transfer with Surface-to-Surface Radiation>Points>Point Heat Source
Heat Transfer with Radiation in Participating Media>Points>Point Heat Source
Ribbon
Physics Tab with 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:
Points>Point Heat Source