Parameters
To add a Parameters node () for creating and defining global parameters:
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From the Model (Windows users) or Main (Mac and Linux users) toolbar click Parameters, or
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Right-click Global Definitions () and select Parameters.
You can also add a Parameters node () under Results () for parameters that you want to use for results analysis and postprocessing without the need to update the solution.
Parameters that you define in a Parameters node under Results have a local context and cannot be defined in terms of global parameters.
If the node has been created previously — there can only be one — the Parameters node is located under the Global Definitions node or the Results node.
Parameters are useful in the following context:
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As parameters in dimensions for geometric primitives or other geometry operations
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As parameters for the mesh generators to, for example, specify the mesh size
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As parameters to control some aspects of the solution process
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To quickly evaluate a mathematical expression, including unit conversion
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In physics interface and feature settings, expressions, and coupling operators
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In expressions when evaluating results
Parameters
Enter values in the Parameters table to define parameters used throughout the entire model (or in nodes under Results only). In the Parameters section you can enter parameters manually or import them from a text file.
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In the Parameters table or the field under the table, enter a parameter Name.
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In the Expression column or field, enter a parameter expression that defines the parameter value, including a unit if desired. You can define a parameter as an expression in terms of numbers, other parameters defined in the same context, built-in constants, and built-in functions of parameters and built-in constants. Also add a unit using unit syntax, unless the parameter is unitless. Press Ctrl+Space (or Ctrl+/) or use the Insert Expression button () below the table to choose from previously defined parameters, mathematical constants and functions, operators, and physical constants that you can insert into the expression at the position of the cursor.
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The Value column displays the value of the parameter in the base unit system.
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In the Description column or field, enter an optional description.
Use the buttons underneath the table to move and remove rows and to clear the table.
Additionally, you can save the parameters to a text file to reuse in other models. Click the Save to File button () and enter a File name in the Save to File dialog box, including the extension .txt. Click Save to store the parameters in a text file or in a Microsoft Excel Workbook spreadsheet if the license includes LiveLink™ for Excel®. The information is saved in space-separated columns in the same order as displayed on screen. When saving to Excel, an Excel Save dialog box appears where you can specify the sheet and range and whether to overwrite existing data, include a header, or use a separate column for units.
You can import or load data in files from a spreadsheet program, for example, with the Load from File button () and the Load from File dialog box that appears. Data must be separated by spaces or tabs. If there is already data in the table, imported parameters are added after the last row. Move or edit rows as needed. If the license includes LiveLink™ for Excel® you can also load parameters from a Microsoft Excel® Workbook spreadsheet. Then an Excel Load dialog box appears where you can specify the sheet and range and whether to overwrite existing data. It is also possible to import from a spreadsheet containing a separate column for units.