Hi, I was looking for the meaning of the "hard_particle yes" command needed for high young's modulus and I don't find the answer. I thought that means the same that hard-sphere, contact by impulsive forces instead of overlap but that doesn't have sense, because I can use hard_particle at the same time as the hertz model that work with overlaps.
I hope someone can help me to understand why this command must be used
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mschramm | Tue, 11/10/2020 - 20:06
numerics
I believe it just comes down to numerical errors that could propagate.
Same thing happens if you try to use a low Young's modulus value. Can't remember what the value is off the top of my head.
jagan1mohan | Wed, 11/11/2020 - 10:48
For hard_particle
If the Youngs Modulus value is less than 1e9 in SI units then we do not have to use any hard_particles flag.
If the problem setup demands a value greater than this limit, we have to use the command 'hard_particles yes' to override the error.
There is also a lower limit for Youngs Modulus, I believe it is 1e5 in SI units. We then use the command 'soft_particles yes' to override the error.