Difference between revisions of "Contrib:KeesWouters/plasticity"

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('''General procedure of the calculation''')
('''General procedure of the calculation''')
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* define the boundary conditions
 
* define the boundary conditions
 
* define the maximum load, in this case a maximum displacement at the plane Pforce
 
* define the maximum load, in this case a maximum displacement at the plane Pforce
* define 'time' and 'load' increments: here we define an increase multiplication factor for the loads from 0 to 1, then constant during a small time and decreasing from 1 to 0 again.
+
* define 'time' and 'load' increments: the time is defined from 0.0 to 2.1 and stepsize 0.1 s, yielding 21 points. An increase multiplication factor is defined for the load from 0 to 1 during the first 1 s, then keep it constant for 0.1 s and decreasing from 1 to 0 in the last second.
 
* perform the analysis
 
* perform the analysis
 
* define results  in a med-file for Salome, in this case, displacements, vonMises and plastic stresses
 
* define results  in a med-file for Salome, in this case, displacements, vonMises and plastic stresses

Revision as of 14:12, 12 August 2009

V shaped construction under plastic deformation

The V shaped is defined by an extrusion of a V shaped face.

Kw vshape1.jpg * Kw vshape2.jpg

Three planes are defined in the geometry: Pleft and Pright for applyind boundary conditions (dx=dy=dz=0) and Pforce for defining a prescribed displacement in y direction.

The definition of the geometry as well as the meshing is given in the Python input file.
In the geometry module of Salome select File --> Load Script (or ctrl T) and thereafter the file: Media:kw_gm_vshape.zip.


General procedure of the calculation

The general procedure of the calculation is as follows:

  • read the mesh
  • apply the non linear material properties of the construction
  • define the boundary conditions
  • define the maximum load, in this case a maximum displacement at the plane Pforce
  • define 'time' and 'load' increments: the time is defined from 0.0 to 2.1 and stepsize 0.1 s, yielding 21 points. An increase multiplication factor is defined for the load from 0 to 1 during the first 1 s, then keep it constant for 0.1 s and decreasing from 1 to 0 in the last second.
  • perform the analysis
  • define results in a med-file for Salome, in this case, displacements, vonMises and plastic stresses
  • print results in a file, notably the displacements of the plane Pforce and its corresponding forces.


Kw res vshape.png

In the figure the results of four load cycles are given: the maximum displacement of each calculation is 0.080, 0.085, 0.095 and 0.100 mm. The plastic deformation at a load free construction after the load cycle is roughly 0.005, 0.009, 0.018 and 0.022 mm.
Each dot in the curves indicate a output point of the calculation. In most case 21 points are given, these have been defined in the 'time' increment function.

tbc