FEM ConstraintSelfWeight

Constraint pressure

Constraint initial temperature

FEM

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

1. There are several ways to invoke the command:
   • Press the ConstraintSelfWeight button.
   • Select the Model → Mechanical Constraints → Constraint self weight option from the menu.
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 magnitude in [mm/s^2], and 0,0,-1 is direction vector.

Solver Z88

• not implemented in Z88 solver (March 2017)

Constraint pressure

Constraint initial temperature

FEM

FEM

• FEM Analysis

• Materials: Solid, Fluid, Nonlinear mechanical, Reinforced (concrete); Material editor

• Element geometry: Beam (1D), Beam rotation (1D), Shell (2D), Fluid flow (1D)

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Constraints

• Electromagnetic: Electrostatic potential, Current density, Magnetization

• Fluid: Initial flow velocity, Initial pressure, Flow velocity

• 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

• Overwrite Constants: Constant vacuum permittivity

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• Mesh: Mesh Netgen, Mesh GMSH, Mesh boundary layer, Mesh region, Mesh group, Nodes set, Mesh to mesh

• Solve: CalculiX Standard, Elmer, Mystran, Z88; Equations: Deformation, Elasticity, Electrostatic, Electricforce, Magnetodynamic, Magnetodynamic 2D, Flow, Flux, Heat; Solver: Solver control, Solver run

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• Utilities: Clipping plane, Remove clipping planes, Open FEM examples; Mesh clear, Mesh display info

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• Additional: Preferences; FEM Install, FEM Mesh, FEM Solver, FEM CalculiX, FEM Concrete; FEM Element Types

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