Component Link
Use a Component Link () to include all items defined within a component under the Components branch () as if they were part of the feature containing the link; see Components.
To add a Component Link, first add a Component, then:
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On the Component toolbar, click the Component Link button ().
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Under Components, right-click Component and add it from the Component node’s context menu.
The Settings window has the following additional section:
Source Component
In the Links from list, choose where to look for a certain property. Available options are:
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Building blocks. Lets you choose among the components listed under Components in the Building Blocks branch. Choose the component from the Link list. Click the Add button () to display a quick menu where you can select a source to add in to the list and use it as the current reference. A Confirm Operation dialog box will appear and ask for confirmation if there is already a reference exist in the Link list. Click the Go to Source button to move to the referenced node in the Link list.
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Built in. Choose from built-in physics interfaces available to the Physics Builder. Select the main resource (COMSOL product) from the Package list. For each resource, choose an interface from the Link list. Only the currently published interfaces are available.
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External resources. Lets you choose among the components listed in an imported builder file under the External Resources branch. Choose the file from the Imported file list. The Link list contains all components found in the Building Blocks>Component branch of the selected file.
When the source component has parameters declared, these are shown in the Component parameters table. The value in the Expression column changes the parameter value for this particular instance of the link. Other links to the same source component can use a different expression. If the source component uses a loop parameter, the Loop parameter table appears. Enter the name of the dependent variable in the Expression column.
Entering Names and Expressions
Component Selection
From the Selection parameter list, select one of the following options:
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 None (the default), to not use a selection parameter.
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 Use selection parameter, to use the Output entities as an input selection for the linked Component node.
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 Use selection loop over product selections, to create a loop over all product selections of the parent and use the Output entities as an input selection for the linked Component node.
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 Use selection loop over nonproduct selections, to create a loop over all nonproduct selections of the parent and use the Output entities as an input selection for the linked Component node.
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 Use selection loop over all selections, to create a loop over all selections of the parent and use the Output entities as an input selection for the linked Component node.
To use a Component Link as a selection loop, the Loop list’s setting in the linked Component node must set to Selection.
When linking from a loop component into another loop component, a Policy for links in loop components list becomes available. From that list, choose one of the following options:
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 Call link for each pass. This is the logical approach were the link is executed in each loop pass of the parent loop component. This option is also applicable for nested links to loop components and simply produces a double loop.
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 Pass along current value for same loop otherwise call in first pass. This option is only applicable for links to loop components and behaves a bit differently depending on what you loop over. If the linked component loops over the same source as the parent loop component, the current loop value is passed along to the linked component for each loop pass. The link is only executed once per loop pass, so there will be no double loop. The effect is the same as if you would pass the loop parameter to a parameter in an ordinary link, but you then cannot use the loop prefix. If the loop sources are different it behaves like the first option: the link is only called in the first loop pass and does a full loop for that link.