Dependent Variable Definition
The Dependent Variable Definition node () is used for the definition of a dependent variable, which means you specify the shape function to use and where that shape function is to be used.
To add a Dependent Variable Definition, first add a Component node under Building Blocks>Components, then:
•
On the Component 1 toolbar, click Dependent Variable Definition (), or
•
Right-click the Component node and select it from the Variables submenu.
The Settings window has the following sections:
Definition
Select a Dependent variable reference: Use physical quantity (the default), Use physical quantity + tag, or Variable name.
•
If you keep the default Use physical quantity, you must first specify the name of the dependent variable in its Settings window, which is selected from the Physical quantity list.
•
For Use physical quantity + tag you can specify an arbitrary unique tag. Enter the tag in the Unique tag field. This tag is added to the end of the name of the Physical quantity chosen. For example, if you choose Area (m^2) from the list and enter house in the Unique tag field, the name for the node (in brackets) in the Physics Builder changes to areahouse.
•
For Variable name, enter a Variable name in the text field.
It is important to have a matching dependent variable setting under the physics interface; otherwise you get an error.
For Use physical quantity (the default), Use physical quantity + tag, choose a Physical quantity from the list. In addition to the predefined physical quantities you can use locally defined physical quantities or physical quantities imported from an external resource:
•
Select Locally defined from the top of the Physical quantity list to use one of the locally defined physical quantities, which you choose 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 Physical Quantity node for the selected local physical quantity.
•
Select Imported from external resource from the Physical quantity list to use physical quantities from another imported Physics Builder file, which you choose from the Imported file list. Click the Go to Source button () to move to the Import node for the imported Physics Builder file.
All dependent variables need a shape function declaration to add the unknowns that the solver solves for. You choose it from the Shape function list. If you are unsure what you need, use the default Lagrange shape function.
To find the definitions of the variable, click the Find Declarations of this Variable button () on the Settings window, or click the node and press F7, or right-click the node and choose Search>Find Definitions.
Selection
The options in the Selection list and Output entities list define the selection where this variable definition is valid. See Specifying Selections for more information.
For the rest of the settings, see the Preferences and Advanced sections for Variable Definition.