FEM ConstraintSelfWeight/en

FEM ConstraintSelfWeight
Menu location
Model → Mechanical Constraints → Constraint self weight
Workbenches
FEM
Default shortcut
C,W
See also
FEM tutorial
Contents 1 FEM ConstraintSelfWeight 2 Description 3 How to use 4 Scripting 5 Solver CalculiX 5.1 Limitations 5.2 Editing CalculiX input file 6 Solver Z88

Description

Constraint self weight defines gravity acceleration 9,81 m/s^2 acting on the whole model in the prescribed direction.

How to use

1. Click on or choose Model → Mechanical Constraints → Constraint self weight from the top menu or press C then W keys.
2. 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 in [mm/s^2]

Solver Z88

• not implemented in Z88 solver (March 2017)