Frequency Domain

) study and study step are used to compute the response of a linear or linearized model subjected to harmonic excitation for one or several frequencies.

For example, in solid mechanics, it is used to compute the frequency response of a mechanical structure with respect to particular load distributions and frequencies. In acoustics and electromagnetics, it is used to compute the transmission and reflection versus frequency. A Frequency Domain study step accounts for the effects of all eigenmodes that are properly resolved by the mesh and how they couple with the applied loads or excitations. The output of a Frequency Domain study step is typically displayed as a transfer function, for example, magnitude or phase of deformation, sound pressure, impedance, or scattering parameters versus frequency.

It is also possible to add an auxiliary sweep to this study step, which creates a multiparameter sweep (Parametric solver) over both the frequency and the given parameters, and optionally with continuation in the frequency or in one of the given parameters. It corresponds to a stationary parametric solver that is preset to linearize the equations (Stationary Solver with a Parametric attribute).

Alternatively, select the check box to use an AWE Solver instead of the Parametric solver.


	The Include geometric nonlinearity check box and the Results While Solving, Mesh Selection, Adaptation and Error Estimates, Geometric Entity Selection for Adaptation, and Auxiliary Sweep section are described in Common Study Step Settings. There is also detailed information in the Physics and Variables Selection and Values of Dependent Variables sections.


	For a problem that requires a linearization point (for example, when the electromechanical forces coupling is used), use the Frequency Domain, Prestressed or the Small-Signal Analysis, Frequency Domain studies instead. These studies include the Stationary step that computes the stationary (or bias) solution followed by the Frequency Domain Perturbation step that computes a perturbed solution around the linearization point from the preceding step.

Study Settings

Select a . This option only appears if there are active least-squares objective functions defined in the model. The default is , which means that the frequency list defined in the field is used. The other possibility is , which means that the frequency list defined by least-squares objectives is used.

Specify the frequencies to use for the frequency sweep. Select the unit to use from the list (default: Hz). Type the frequencies in the field using space-separated numbers or the range function.

Use the field to select a file with parameter values. You can browse your file system for files by clicking the button (

). You can also click the downward arrow beside the button and choose (

) to open the fullscreen window. Click the downward arrow for the menu (

) to choose (

) to move to the row for this file in the window, (

), and (if you have copied a file location) (

). After selecting a file, click the button (

) to load the parameter values into the field.

For information about the list, see Reuse Solution from Previous Step List.

Study Extensions

Also see Auxiliary Sweep.

Asymptotic Waveform Evaluation

Select the check box to enable the asymptotic waveform evaluation (AWE) solver. The Frequency Domain study generates a solver configuration that is used to solve a stationary parametric problem or an asymptotic waveform evaluation problem. By selecting this check box, this study step corresponds to an AWE Solver.

Distribute Parametric Solver

If you are running a parametric sweep and want to distribute it by sending one parameter value to each compute node, select the check box. This requires that your study includes a parametric sweep. To enable this option, click the button (

) and select in the dialog box.