# contact problem of applying ScGeom on polyhedra particle

hello

i was applying Ig2_Polyhedra_

below is my code:

from yade import polyhedra_

import random

n = FrictMat(

O.materials.

#the boundary of particle deposit

v1=((0,

v2=((0,

v3=((0,

v4=((0,

v5=((3,

b1 = polyhedra_

b2 = polyhedra_

b3 = polyhedra_

b4 = polyhedra_

wall = polyhedra_

b2.shape.wire=True

O.bodies.

polyhedra_

O.engines = [

ForceResett

InsertionSo

Interaction

),

# GravityEngine(

NewtonInteg

PyRunner(

]

O.dt=1e-5

## Question information

- Language:
- English Edit question

- Status:
- Answered

- For:
- Yade Edit question

- Assignee:
- No assignee Edit question

- Last query:
- 2019-06-03

- Last reply:
- 2019-06-03

Jan Stránský (honzik) said : | #1 |

Hello,

> i have tried many value of time step

what values (or at least in what range)?

As always in this kind of problem, you can try to increase stiffness.

The repulsive force is computed proportionally to penetration volume, you can try to use thicker walls or true Yade Wall (where the semi-space penetration is computed, not just true intersection of a polyhedron and thin box.

cheers

Jan

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