COMSOL 6.2 - Physics Nodes — Equation Section

For each physics node there is an section that is available by default in the window. This section has options to display mathematical equations applicable to the node.

	If you do not want to display the Equation section, click the Show More Options button () and clear the Equation Sections check box in the Show More Options dialog box.

	Equation View

The display options available from the lists depend on the study types and other physics-specific factors. See Figure 3-20 for an example comparing the equations that display for a or study for a interface. Some windows do not have any options and only display the relevant equation and other windows have additional sections that become available for the display based on the study type selected.

	Study and Study Step Types

For all physics nodes (excluding the main physics interface node level), the equation that displays includes a dotted line underneath where the node’s contribution is made to the equation. See Figure 3-19 for an example where a section of the heat transfer equation is underlined, indicating where the node contributes to it.

When you add physics interfaces to a Component, the supported are listed in the list. is the default; select another option as needed. When the setting is , the study controls the equation form — stationary or time dependent, for example — for the physics interface. In some cases, that equation form might not be compatible with the physics covered by the physics interface; the physics interface then uses its default equation form (typically, a stationary equation form). You can then instead choose one of the supported study types.

The option is available by default when is selected (or left as the default) as the . Options availability is based on the studies added and defined for the model.

For the following options — frequency and mode analysis frequency — you also have the option to use another frequency than the one used by the solver. This can be necessary if you need two different frequencies for two physics interfaces.

This option is available if is selected as the . The default uses the frequency . If is selected, enter another value or expression (SI unit: Hz).

This option is available if or is selected as the . Enter a value or expression in the field (SI unit: Hz). Specify a frequency (it is not present as a solver variable).

This option is available with the RF Module interface and if is selected as the . Enter a value in the field (unitless).