> I'm trying to do some simulations using periodic cell. In one case, I > prescribed some extension of the periodic cell, but the particles in the > simulation behave really strange - the dispacement of particles si > continuously increasing.
I had a look again. It looks as if kinetic energy is increasing, even with damping=0.9. I tried with Law2_Dem3DofGeom_FrictPhys_Basic and also Law2_ScGeom_FrictPhys_Basic (instead of the Cpm law) and the result is always the same: spheres bumping into each other going crazy after a short while. What is happening?? Can someone have a look as well? Especially tracking stored elastic and kinetic energy could be useful. (there is no plasticity involved) The script is attached (run with -j1, it might be faster). Weird thing. Václav
from yade import pack, log, qt import itertools # create material O.materials.append(CpmMat(young=1e7,epsCrackOnset=20,relDuctility=3,sigmaT=3e30,frictionAngle=.5,G_over_E=.2)) O.periodic=True # create 3x3x3 particles a=1.; r=a/6. for i,j,k in itertools.product(range(3),repeat=3): O.bodies.append(utils.sphere([(2*i-1)*r,(2*j-1)*r,(2*k-1)*r],r)) O.cell.refSize=(a,a,a) O.engines=[ BoundDispatcher([Bo1_Sphere_Aabb()]), InsertionSortCollider(), InteractionDispatchers( [Ig2_Sphere_Sphere_ScGeom()],[Ip2_FrictMat_FrictMat_FrictPhys()],[Law2_ScGeom_FrictPhys_Basic()]), ## the same with other consitutive laws: # [Ig2_Sphere_Sphere_Dem3DofGeom(distFactor=-1)],[Ip2_CpmMat_CpmMat_CpmPhys(cohesiveThresholdIter=-1)],[Law2_Dem3DofGeom_CpmPhys_Cpm()]), # [Ig2_Sphere_Sphere_Dem3DofGeom()],[Ip2_FrictMat_FrictMat_FrictPhys()],[Law2_Dem3DofGeom_FrictPhys_Basic()]), NewtonIntegrator(damping=0.8) ] # forced compression of periodic cell along x O.cell.trsf+=Matrix3(-.01,0,0, 0,0,0, 0,0,0) O.dt=1e-9
_______________________________________________ Mailing list: https://launchpad.net/~yade-users Post to : [email protected] Unsubscribe : https://launchpad.net/~yade-users More help : https://help.launchpad.net/ListHelp
