FEM ConstraintSelfWeight
|
Menu location |
---|
Model → Mechanical Constraints → Constraint self weight |
Workbenches |
FEM |
Default shortcut |
None |
Introduced in version |
- |
See also |
FEM tutorial |
Description
Constraint self weight defines gravity acceleration 9,81 m/s^2 acting on the whole model in the prescribed direction.
Usage
- There are several ways to invoke the command:
- Press the
FEM ConstraintSelfWeight button.
- Select the Model → Mechanical Constraints →
Constraint self weight option from the menu.
- Press the
- You can modify the direction of gravitation by changing its vector coordinates in the property bar of newly created ConstraintSelfWeight object.
Scripting
New object:
import ObjectsFem
ObjectsFem.makeConstraintSelfWeight(name)
Add object to the analysis named Analysis:
App.ActiveDocument.Analysis.Member = App.ActiveDocument.Analysis.Member + [(object)]
Example:
import ObjectsFem
selfweight_obj = ObjectsFem.makeConstraintSelfWeight("MySelfWeightObject")
App.ActiveDocument.Analysis.Member = App.ActiveDocument.Analysis.Member + [selfweight_obj]
Solver CalculiX
Limitations
- You need to modify .inp file to edit gravity acceleration.
- Self weight is applied to the element set Eall means to the whole model.
Editing CalculiX input file
Acceleration constant can be edited by hand modification after generating CalculiX input file.
Example of lines in .inp file:
*DLOAD
Eall,GRAV,9810,0.0,0.0,-1.0
where 9810 is gravity acceleration magnitude in [mm/s^2], and 0,0,-1 is direction vector.
Solver Z88
- not implemented in Z88 solver (March 2017)
- Materials: Solid, Fluid, Nonlinear mechanical, Reinforced (concrete); Material editor
- Element geometry: Beam (1D), Beam rotation (1D), Shell (2D), Fluid flow (1D)
Constraints
- Electromagnetic: Electrostatic potential, Current density, Magnetization
- Geometrical: Plane rotation, Section print, Transform
- Mechanical: Fixed, Displacement, Contact, Tie, Spring, Force, Pressure, Centrif, Self weight
- Thermal: Initial temperature, Heat flux, Temperature, Body heat source
- Without solver: Fluid boundary, Bearing, Gear, Pulley
- Overwrite Constants: Constant vacuum permittivity
- Solve: CalculiX Standard, CalculiX (new framework), Elmer, Mystran, Z88; Equations: Deformation, Elasticity, Electrostatic, Electricforce, Magnetodynamic, Magnetodynamic 2D, Flow, Flux, Heat; Solver: Solver control, Solver run
- Results: Purge, Show; Postprocessing: Apply changes, Pipeline from result, Warp filter, Scalar clip filter, Function cut filter, Region clip filter, Contours filter, Line clip filter, Stress linearization plot, Data at point clip filter, Filter function plane, Filter function sphere, Filter function cylinder, Filter function box
- Additional: Preferences; FEM Install, FEM Mesh, FEM Solver, FEM CalculiX, FEM Concrete; FEM Element Types

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