A variable that has a shape function definition needs an initial value for nonlinear and transient simulations. In the Degree of Freedom Initialization node () you define the initial value for such variable definitions. You can also use this to set the initial condition for dependent variables, but it is recommended that you use the Initial Values node instead. In situations where you do not want the Initial value feature in the Model Builder, you can customize the initial value definition using this node.

To add a Degree of Freedom Initialization, first add a Component node under Building Blocks>Components, then:

The Settings window has the following sections:

You type the name of the variable you add the initial value for in the Variable name field. The variable name follows the rules described in Entering Names and Expressions, and must match the name of a variable declaration somewhere in the same physics interface. The name should also be the name of a variable that has a shape definition, but no errors result if this is not the case. Select the Set initial value on time derivatives check box to add the initial values for the first time derivative.

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.

The rest of the settings are described in the Preferences and Protection section for Variable Definition.