questions about Kn and Ks

> (1). According to my simulation requirement, all the particls in specimen
> must have the same
> Kn and Ks which are all equal to 4e5.
>

Kn and Ks are attributes of interactions. when new interaction is created,
this Kn and Ks are evaluated according to formulas from your previous email.

> (2). From these equations:
> Kn=2.*E*R1*E*R2/(E*R1+E*R2) (1)
> Ks/Kn=P (2)
> I can obviously understand that all particles can not have the same values
> of "young" for that the radii of them are not the same. But I failed to get
> a correct input of "young" because the order may force me to do in this
> way(one type material can only be assigned only one value of "young"):
>
> # spheremat =
> O.materials.append(FrictMat(poisson=0.5,density=1500,young=1.48e8,frictionAngle=0.7))
>
>
in your script, tou have unifrrom radius, so you can identify E and P from
equations (1) and (2). If you have nonuniform particle radii and you want
Kn and Ks, this is quite non-standard requirement (btw, why do you want is
so?). Just now I don't know how to solve it with existing code, I will
think about it..

cheers
Jan

fixed typo from my previous answer:
In your script, you have unifrrom radius, so you can identify E and P
from equations
(1) and (2). If you have nonuniform particle radii and you want smae Kn and
Ks for all interactions, this is quite non-standard requirement (btw, why
do you want it so?).

Hi,

I think there is another way, but I really don't recommend it.

If you are using the source code, you can go to the Ip2 functor, for instance: Ip2_FrictMat_FrictMat_FrictPhys.cpp and set:

contactPhysic->kn = your value
contactPhysic->ks = your value

Viet

Thanks Bruno Chareyre, that solved my question.