Stationary
The Stationary () study and study step are used when field variables do not change over time, such as in stationary problems.
In electromagnetics, it is used to compute static electric or magnetic fields, as well as direct currents. In heat transfer, it is used to compute the temperature field at thermal equilibrium. In solid mechanics, it is used to compute deformations, stresses, and strains at static equilibrium. In fluid flow, it is used to compute the steady flow and pressure fields. In chemical species transport, it is used to compute steady-state chemical composition in steady flows. In chemical reactions, it is used to compute the chemical composition at equilibrium of a reacting system.
It is also possible to compute several solutions, such as a number of load cases or to track the nonlinear response to a slowly varying load.
A Stationary study step node corresponds to a Stationary Solver (the default) or a parametric solver.
There is also an option to run a Stationary study with an Auxiliary sweep, with or without a continuation parameter. When a continuation parameter is selected, the continuation algorithm is run, which assumes that the sought solution is continuous in these parameters. If no continuation parameter is given, a plain sweep is performed where a solution is sought for each value of the parameters. In both cases, a Stationary Solver node plus a Parametric attribute is used. The parametric solver is the algorithm that is run when a Parametric attribute node is active under a Stationary Solver node. Similarly, when the mesh adaptation solver is the algorithm that is run, an Adaptive Mesh Refinement subnode is added under a Stationary Solver node.
When there are active least-squares objective functions in the model, it is possible to run an Auxiliary sweep with least-squares defined parameters if there are any. To use this possibility, choose From least-squares objective from the Parameter list method list. Otherwise, Parameter list method is set to Manual. This option is hidden if there are no least-squares objectives in the model.
The Study Settings, Physics and Variables Selection, Values of Dependent Variables, Mesh Selection, Adaptation and Error Estimates, and Geometric Entity Selection for Adaptation sections are described in Common Study Step Settings. There is also detailed information in the Physics and Variables Selection and Values of Dependent Variables sections. Note that the Study Settings section is empty if there is no Include geometric nonlinearity check box or Parameter list method list.
Results While Solving
Select the Plot check box to allow plotting of results while solving. Then select what to plot from the Plot group and Update at lists. The software plots the dataset of the selected plot group as soon as the results become available. Select Times stored in output (the default) or Time steps taken by solver from the Update at list.
Use the Probes list to select any probes to evaluate. The default is All, which selects all probes for plotting and tabulation of probe data. Select Manual to open a list with all available probes. Use the Move Up (), Move Down (), Delete (), and Add () buttons to make the list contain the probes that you want to see results from while solving. Select None to not evaluate any probe.
The software plots the dataset of the selected plot group and probes as soon as the results become available. Select Steps stored in output (the default) or Steps taken by solver from the Update at list.
Study Extensions
This section contains some optional extensions of the study, such as Auxiliary Sweep (including continuation) and load cases.
Load Cases
Select the Define load cases check box to define load cases as combinations of defined load groups, multiplied with optional weights (load factors), and constraint groups. When this check box is selected, and a Parametric attribute node is also used, the load cases are also displayed under the Load Cases section for the Parametric node.
Load cases are useful for efficiently solving for a number of cases with varying loads (and constraints) in the same model without the need to reassemble the stiffness matrix. Use the Move Up (), Move Down (), Delete (), and Add () buttons to make the list contain the load cases that you want to solve for. For each load case, click in the column for the load groups and constraint groups that you want to include in the load case. By default, no load groups and constraint groups are included (). Load groups and constraint groups that are included appear with a check mark (). Optionally, change the default weights for the load groups from 1.0 to another value in the corresponding Weight column (which is to the right of the load group that it is acting on). A weight of 1.5, for example, adds an extra 50% to the magnitude of the loads in the load group; a weight of 1 reverses the direction of the loads.
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 Distribute parametric solver check box. This requires that your study includes a parametric sweep. To enable this option, click the Show More Options button () and select Bath and Cluster in the Show More Options dialog box.