FEM ConstraintSelfWeight

From FreeCAD Documentation
The printable version is no longer supported and may have rendering errors. Please update your browser bookmarks and please use the default browser print function instead.
This page is a translated version of the page FEM ConstraintSelfWeight and the translation is 41% complete.
Outdated translations are marked like this.
Other languages:

FEM ConstraintSelfWeight

Системное название
FEM ConstraintSelfWeight
Расположение в меню
FEM → Constraint self weight
Верстаки
FEM
Быстрые клавиши
C,W
Представлено в версии
-
См. также
FEM tutorial

Описание

Defines a gravity acceleration acting on the whole model in the prescribed direction.

version 0.21 and below: The acceleration has a fixed value of 9.81 m/s^2.

Применение

  1. There are several ways to invoke the command:
    • Press the Gravity load button.
    • Select the Model → Mechanical boundary conditions and loads → Gravity load option from the menu.
  2. A ConstraintSelfWeight object is created.
  3. introduced in version 0.22: Optionally change its ДанныеGravity Acceleration property.
  4. Optionally change its ДанныеGravity Direction property.

Программирование

New object:

import ObjectsFem
ObjectsFem.makeConstraintSelfWeight(name)

Add object to the analysis named Analysis:

App.ActiveDocument.Analysis.Member = App.ActiveDocument.Analysis.Member + [(object)]

Пример:

import ObjectsFem
selfweight_obj = ObjectsFem.makeConstraintSelfWeight("MySelfWeightObject")
App.ActiveDocument.Analysis.Member = App.ActiveDocument.Analysis.Member + [selfweight_obj]

Решатель CalculiX

Limitations

  • version 0.21 and below: You need to modify the .inp file to edit gravity acceleration.
  • Self-weight is applied to the element set Eall which includes the whole model.

Editing CalculiX input file

The acceleration constant can be manually edited after generating the CalculiX input file.

Example of lines in the .inp file:

*DLOAD
Eall,GRAV,9810,0.0,0.0,-1.0

where 9810 is a gravity acceleration magnitude in [mm/s^2], and 0,0,-1 is the direction vector. The value can be set as a multiple of standard gravity acceleration to simulate loading of e.g. 4g.

Решатель Z88

  • Currently, not implemented in the Z88 solver.