Default Model Inputs
The Default Model Inputs node () can be added under Global Definitions to define constant values for model inputs that are used by default for the entire model. Right-click Global Definitions and choose Default Model Inputs to display or hide the Default Model Inputs node. The Default Model Inputs node also appears if it is hidden when a model input is requested (for example, from a material that is dependent on temperature). If you select the Group by Type option, the Default Model Inputs node appears under a Shared Properties node.
The default model inputs include most physical properties and are always available with a scalar default value. In the settings for the Default Model Inputs node you can change the default values, and you can also override them locally either by a dependent variable (field variable) for the same quantity or by a locally defined Model Input node (see Model Input).
Default model inputs are useful in the following ways:
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Model inputs have a central representation as a variable. The value of a model input variable can differ between components and geometry regions.
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There is no need, in most cases, to use a local model input in the physics interfaces.
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Any material using a model input will use the default model input, unless something else is specified.
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It makes it possible to use, for example, a temperature-dependent material property in a PDE interface, which can be evaluated as a default model input, possibly overridden by a local model input or by a temperature field from a Heat Transfer interface defined in the same component geometry.
Click the Refresh button () to update the Requested Model Inputs section and the Model input contributions list in the Browse Model Inputs section to the latest changes in a physics feature, a material, or a coupling feature.
Click the Reset All button () to reset all values to their default values.
The Settings window contains the following sections:
Requested Model Inputs
In this section any requested model inputs from the physics or materials appear.
The table of requested model inputs contains the following columns:
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The Model input column contains the names of the requested model inputs such as Temperature.
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The Expression column contains the expression that defines the model input, such as comp1.T for a temperature field in Component 1. The column will be editable if it does not contain an automatically matched quantity such as comp1.T for an existing temperature field. For example, if the expression comes from a Model Input node under Definitions in a model component. If the model input is editable, click the Edit Expression button () underneath the table. You can also right-click the cell and choose, for example, Edit Expression for Remaining Selections to enter another value for remaining selections in the text field for the model input under Expression for remaining selections in the Browse Model Inputs section. The Expression column can also contain the value Mixed, which indicates an expression that is requested in two selections, and the expression is different on each selection (for example, it is a temperature field in one domain and a user-defined model input in another).
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The icon column contains an icon for the material or physics that requested the model input.
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The Selection column contains the geometric selection for the model input.
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The Requested by column contains the node that requested this model input. Click the Go to Requesting Node button () to move to that node.
Click the Create Model Input button () to create a local Model Input node that you can use to override the global model input in some part of the component geometry.
Browse Model Inputs
In this section, you can select a physical quantity (all physical quantities can serve as model inputs) from the General, Acoustics, Maxwell, Solid, and Transport folders. You can also type in a physical quantity in the text field above the list and click the Filter button () to filter the list of model inputs. If the Show Only Contributed and Requested Model Inputs button () is active, the list of physical quantities only contains such physical quantities that are either contributed or requested model inputs.
When you have selected a model input, its default value is displayed below the list of model inputs under Expression for remaining selection, for example. The default value is a constant value, which can be useful, for example, for evaluating an expression that used a model input before computing a solution. For many model inputs, the default value is 0, but for Temperature, for example, it is 293.15 K (20 degrees Celsius). You can change that value if you want to use another value for the temperature as a default model input, for example. Click the Reset to Default button () to reset the value it the default value for that model input.
In the table under Model input contributions, the left column contains value of the model input, the Selection column contains its selection (Remaining, for example). The icon column contains an icon that represents the interface, or the Default Model Inputs node itself (), that contains the provider that contributed a model input. The Provider column contains the name of the provider of the model input.
Every physical quantities that can act as model inputs declares and defines a common variable that is always available (for example, minput.T for the temperature T). Any material property that depends on a model input quantity can be evaluated using the common variable.
About Model Inputs