yade-dev team mailing list archive

[Vincent Richefeu <richefeu@xxxxxxxxxxxxxxx>]

> Does it mean, that if I have 3 particles from 3 different materials  
> I can make the next "database":
>
> P1-P2 - Kn(1-2); Kt(1-2)...;
> P2-P3 - Kn(2-3); Kt(2-3)...;
> P1-P3 - Kn(1-3); Kt(1-3)...;
> P1-P1 - Kn(1-1); Kt(1-1)...;
> P2-P2 - Kn(2-2); Kt(2-2)...;
> P3-P3 - Kn(3-3); Kt(3-3)...;
>
> Particle interaction from different materials will use different  
> parameters from "database" depending on materials participated in  
> interactions?

Yes, this simple "solution" is very intuituve and it should be an  
alternative to the current solution that anoying me sometimes because  
of arbitrary choice (does frictionAngle should be the min/max/ 
mean/... value?).
I think that both these solutions can coexist although the new one  
should be improved...

Practically, you don't need to fill the "database-parameters" one by  
one. You simply say somethink like:
"There are two groupMasks": ngrp 2
"I declare the parameter Kn": parameter Kn
(It means that Kn(0-0) = Kn(0-1) = Kn(1-0) = Kn(1-1) = 0.0)
"I want that all Kn are 1e6": setall Kn 1e6
((It means that Kn(0-1) = Kn(1-0) = 1e8)
"I want that Kn between 0 and 1 is 1e8": set Kn 0 1 1e8
((It means that Kn(0-1) = Kn(1-0) = 1e8)
etc.

In *Relationships classes, we could do somethink like this:

// ...
contactPhysics* c = "cast...";
grpRelationData* data = "cast grpRelationData in Omega()";

if (data->isActivated())
{
  mask1 = "from cast of Omega...bodies with interaction id1";
  mask2 = "from cast of Omega...bodies with interaction id2";
  if (data->exists("Kn")) c->kn = data->getParameter 
("Kn",mask1,mask2); else c->kn = 0.0;
  if (data->exists("Kt")) c->kt = data->getParameter 
("Kt",mask1,mask2); else c->kt = 0.0;
  // etc.
}
else
{
// current solution
}

I will add it in BasicViscoelasticRelationships...

VR