particles not subject to deformation

Asked by JOHN

Good evening,
I noticed during a simple simulation that my particles deformed elastically. However, when i increased the young or poisson parameter i got a substantially slower simulation. My question is, is there a way to declare the particlicles non deformable without changing the simulation speed?

Thank you for your help
JOHN

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Yade Edit question
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Solved by:
Jérôme Duriez
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Best Jérôme Duriez (jduriez) said :
#1

Hello,

In short: no.
Because the critical (maximum) timestep varies with 1 / squareRoot(contact stiffness). Increasing contact stiffness (through increasing FrictMat.young or .poisson, assuming you're using Ip_FrictMat_FrictMat_FrictPhys) thus automatically decreases your time step, and most probably increases the required number of DEM iterations, if this is what you intend with "simulation speed".

However, because the critical timestep also varies with squareRoot(particle mass), increasing particles masses may help in some cases, you may search "density scaling" through the DEM literature.

This being said, if you're really looking for "particles not subject to deformation"/"non deformable", I would advice stop using YADE right away and look for Contact Dynamics codes (like LMGC90, here in France).

Jérôme

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Bruno Chareyre (bruno-chareyre) said :
#2
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JOHN (washingmachine) said :
#3

Thanks Jérôme Duriez, that solved my question.