yade-dev team mailing list archive

[Bruno Chareyre <bruno.chareyre@xxxxxxxxxxx>]

> For completeness I should have included also Ks/Kn. They are all
> parameters of the interaction, however do they have a specific
> physical-basis? I am not saying that it is wrong to employ them, that is
> indeed a common assumption in a dem model.

I'm too sure what is a "physical" parameter (for some physicists, Young modulus and
internal friction angle are not physical parameters but engineers tricks).

We have constitutive relations (the mathematical form) and constitutive parameters (the
constants in there). It is logical to define constitutive parameters at the bodies level.
Just giving a very practical reason here : I have particles of type A and B, and I want
different values of friction for interactions A-A, A-B, and B-B (don't ask why there
should be different, it is my constitutive assumption). How could I achieve that if
friction was defined in the Ip functor directly?
Be it friction, kn, ks, ktw, kroll or adhesion, it makes no difference.

> As we all know, those
> parameters are generally quantified to obtain realistic behaviour at the
> macro-scale.

Generally, not always. You, for instance, are not doing that.

Bruno