FEM EquationDeformation

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FEM EquationDeformation

Menu location
Solve → Deformation equation
Workbenches
FEM
Default shortcut
None
Introduced in version
1.0
See also
Elasticity equation

Description

This equation describes the nonlinear elastic deformation of rigid bodies.

For info about the math of the equation, see the Elmer models manual, section Finite Elasticity.

Usage

  1. After adding an Elmer solver as described here, select it in the tree view.
  2. Now either use the toolbar button or the menu Solve → Deformation equation.
  3. Change the equation's solver settings or the general solver settings if necessary.

Solver Settings

For the general solver settings, see the Elmer solver settings.

The deformationequation provides these special settings:

  • DataCalculate Pangle: If the principal angles should be calculated.
  • DataCalculate Principal: If all stresses should be calculated.
  • DataCalculate Strains: If strains will be calculated. This will also calculate the stresses, even if DataCalculate Principal or DataCalculate Stresses is false.
  • DataCalculate Stresses: If stresses should be calculated. Compared to DataCalculate Principal the Tresca yield criterion and the principal stress will not be calculated.
  • DataConstant Bulk System: See the Elmer manual for more info.
  • DataVariable: The variable for the elasticity equation. Only change there the 3 to 2 if you have a 2D geometry.

Equation:

  • DataPlane Stress: Computes solution according to the plane stress situation. Applies only for 2D geometry.

Constraint Information

The elasticity equation takes the following constraints into account if they are set:

Note

Except for calculations in 2D, for all above constraints it is important that they act on a face. Constraints for 3D set to lines or vertices are not recognized by the Elmer solver.

Results

The available results depend on the solver settings. If none of the DataCalculate * settings was set to true, only the displacement is calculated. Otherwise also the corresponding results will be available.