FEM ConstraintSelfWeight: Difference between revisions

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<languages/>
<translate>
<translate>

<!--T:14-->
{{Docnav
|[[FEM_ConstraintPressure|Constraint pressure]]
|[[FEM_ConstraintInitialTemperature|Constraint initial temperature]]
|[[FEM_Module|FEM]]
|IconL=FEM_ConstraintPressure.svg
|IconR=FEM_ConstraintInitialTemperature.svg
|IconC=Workbench_FEM.svg
}}

<!--T:1-->
<!--T:1-->
{{GuiCommand
{{GuiCommand|Name=FEM ConstraintSelfWeight|MenuLocation=FEM → Constraint self weight||Workbenches=[[Fem Workbench|FEM]]|Shortcut=C,W|SeeAlso=[[FEM_tutorial|FEM tutorial]]}}
|Name=FEM ConstraintSelfWeight
|MenuLocation=Model → Mechanical Constraints → Constraint self weight
|Workbenches=[[FEM_Module|FEM]]
|SeeAlso=[[FEM_tutorial|FEM tutorial]]
}}


==Description== <!--T:2-->
==Description== <!--T:2-->

<!--T:12-->
Constraint self weight defines gravity acceleration 9,81 m/s^2 acting on the whole model in the prescribed direction.
Constraint self weight defines gravity acceleration 9,81 m/s^2 acting on the whole model in the prescribed direction.


==How to use== <!--T:3-->
==Usage== <!--T:3-->
#Click on [[Image:FEM ConstraintSelfWeight.png|32px]] or choose {{KEY| FEM}} → {{KEY|[[Image:FEM ConstraintSelfWeight.png|32px]] Constraint self weight}} from the top menu or press {{KEY|C}} then {{KEY|W}} keys.
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#You can modify the direction of gravitation by changing its vector coordinates in the property bar of newly created ConstraintSelfWeight object.


==Scripting==<!--T:4-->
<!--T:13-->
# There are several ways to invoke the command:
#* Press the {{Button|[[Image:FEM_ConstraintSelfWeight.svg|16px]] [[FEM_ConstraintSelfWeight|ConstraintSelfWeight]]}} button.
#* Select the {{MenuCommand|Model → Mechanical Constraints → [[Image:FEM_ConstraintSelfWeight.svg|16px]] Constraint self weight}} option from the menu.
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# You can modify the direction of gravitation by changing its vector coordinates in the property bar of newly created ConstraintSelfWeight object.


==Scripting== <!--T:4-->
== Solver specific informations ==

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=== CalculiX ===
===Limitations===<!--T:5-->
<!--T:7-->
'''New object'''
</translate>
{{Code|code=
import ObjectsFem
ObjectsFem.makeConstraintSelfWeight( name )
}}
<translate>

<!--T:8-->
'''Add object to the analysis named Analysis'''
</translate>
{{Code|code=
App.ActiveDocument.Analysis.Member = App.ActiveDocument.Analysis.Member + [ (object) ]
}}
<translate>

<!--T:9-->
'''Example:'''
</translate>
{{Code|code=
import ObjectsFem
selfweight_obj = ObjectsFem.makeConstraintSelfWeight( 'MySelfWeightObject' )
App.ActiveDocument.Analysis.Member = App.ActiveDocument.Analysis.Member + [selfweight_obj]

}}
<translate>

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== Solver CalculiX == <!--T:5-->
===Limitations===
*You need to modify .inp file to edit gravity acceleration.
*You need to modify .inp file to edit gravity acceleration.
*Self weight is applied to the element set Eall means to the whole model.
*Self weight is applied to the element set Eall means to the whole model.


===Editing CalculiX input file===
===Editing CalculiX input file=== <!--T:10-->
Acceleration constant can be edited by hand modification after generating CalculiX input file.
Acceleration constant can be edited by hand modification after generating CalculiX input file.


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Eall,GRAV,9810,0.0,0.0,-1.0
Eall,GRAV,9810,0.0,0.0,-1.0
}}
}}
where 9810 is gravity acceleration in [mm/s^2]
where 9810 is gravity acceleration magnitude in [mm/s^2], and 0,0,-1 is direction vector.

== Solver Z88 == <!--T:11-->
* not implemented in Z88 solver (March 2017)


<!--T:15-->
{{Docnav
|[[FEM_ConstraintPressure|Constraint pressure]]
|[[FEM_ConstraintInitialTemperature|Constraint initial temperature]]
|[[FEM_Module|FEM]]
|IconL=FEM_ConstraintPressure.svg
|IconR=FEM_ConstraintInitialTemperature.svg
|IconC=Workbench_FEM.svg
}}


</translate>
</translate>
{{FEM Tools navi{{#translation:}}}}
{{Userdocnavi{{#translation:}}}}
{{clear}}
{{clear}}
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<languages/>

Revision as of 19:39, 26 February 2021

Other languages:

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)


FEM

Constraints

User documentation
Retrieved from "http://wiki.freecad.org/index.php?title=FEM_ConstraintSelfWeight&oldid=860006"