Re: [Yade-users] [Question #291202]: Clumping - angl of repose
Question #291202 on Yade changed: https://answers.launchpad.net/yade/+question/291202 Status: Open => Answered Christian Jakob proposed the following answer: Hi, I did not investigate your script very deeply, but I guess the explosion arises from replaceByClumps() function. A workaround for avoiding explosions is given in the original example line 81 and following ... https://github.com/yade/trunk/blob/master/examples/clumps /replaceByClumps-example.py#L81 Cheers, Christian -- You received this question notification because your team yade-users is an answer contact for Yade. ___ Mailing list: https://launchpad.net/~yade-users Post to : yade-users@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-users More help : https://help.launchpad.net/ListHelp
Re: [Yade-users] [Question #291202]: Clumping - angl of repose
Question #291202 on Yade changed: https://answers.launchpad.net/yade/+question/291202 Status: Answered => Open Seti is still having a problem: Yes, I have even tried O.dt=.1*utils.PWaveTimeStep() , no different ! -- You received this question notification because your team yade-users is an answer contact for Yade. ___ Mailing list: https://launchpad.net/~yade-users Post to : yade-users@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-users More help : https://help.launchpad.net/ListHelp
Re: [Yade-users] [Question #291202]: Clumping - angl of repose
Question #291202 on Yade changed: https://answers.launchpad.net/yade/+question/291202 Seti gave more information on the question: Yes, I have even tried O.dt=.1*utils.PWaveTimeStep() , no difference! -- You received this question notification because your team yade-users is an answer contact for Yade. ___ Mailing list: https://launchpad.net/~yade-users Post to : yade-users@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-users More help : https://help.launchpad.net/ListHelp
Re: [Yade-users] [Question #291202]: Clumping - angl of repose
Question #291202 on Yade changed: https://answers.launchpad.net/yade/+question/291202 Status: Open => Answered Jérôme Duriez proposed the following answer: Have you tried to play with (decrease) the timestep ? Excessively high timesteps are a classical reason for "explosion" -- You received this question notification because your team yade-users is an answer contact for Yade. ___ Mailing list: https://launchpad.net/~yade-users Post to : yade-users@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-users More help : https://help.launchpad.net/ListHelp
Re: [Yade-users] [Question #291202]: Clumping - angl of repose
Question #291202 on Yade changed: https://answers.launchpad.net/yade/+question/291202 Seti gave more information on the question: I think this explosion is depended on percentage of clumping . I mean by increasing the ratio of clumping the sample explode sooner. I am not sure what is the conflict. Does anybody experience in this regard. Thanks Seti -- You received this question notification because your team yade-users is an answer contact for Yade. ___ Mailing list: https://launchpad.net/~yade-users Post to : yade-users@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-users More help : https://help.launchpad.net/ListHelp
Re: [Yade-users] [Question #291202]: Clumping - angl of repose
Question #291202 on Yade changed: https://answers.launchpad.net/yade/+question/291202 Status: Answered => Open Seti is still having a problem: Hi Kalus, Thanks for your response . I have tried to use mackeCloud , easily as per below, However I have the same problem. Would you please? from yade import pack,utils, qt, plot #create material soil1 = CohFrictMat(young=30e9,poisson=0.3,frictionAngle=radians(30),density=2600.0,normalCohesion=1e6, shearCohesion=80e6,label='soil') #color=(1,0,0) red color O.materials.append(soil1) O.bodies.append(utils.wall(0,axis=1,sense=1)) O.materials.append(CohFrictMat(young=30e9,poisson=0.3, frictionAngle = radians(30) , label='wallmat')) wallmat = O.materials[-1] sp=SpherePack() sp.makeCloud((0,0,0),(14.5,14.5,14.5),rMean=0.5,rRelFuzz=0.0) #sp.makeCloud((0,0,0),(14.5,14.5,14.5),rMean=0.2,rRelFuzz=0.0,False,0.95,[0.2,0.3,0.4,0.5,0.6,0.7,0.8],[0.14,0.28,0.34,0.50,0.65,0.85,1.00]) #spheres.toSimulation() sp.toSimulation() #O.bodies.append(spheres) -- You received this question notification because your team yade-users is an answer contact for Yade. ___ Mailing list: https://launchpad.net/~yade-users Post to : yade-users@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-users More help : https://help.launchpad.net/ListHelp
Re: [Yade-users] [Question #291202]: Clumping - angl of repose
Question #291202 on Yade changed: https://answers.launchpad.net/yade/+question/291202 Status: Open => Answered Klaus Thoeni proposed the following answer: Hi, you are using randomDensePack to generate your assembly. The function uses TriaxialTest [1] so the packing you get is most certain not stress- free, i.e., particles will have overlap, hence you get an explosion. This should be the case for spheres and clumps. Try using makeCloud [2] instead or make your dense sample stress-free by shrinking the spheres which overlap. HTH K [1] https://yade-dem.org/doc/yade.pack.html?highlight=randomdensepack#yade.pack.randomDensePack [2] https://yade-dem.org/doc/yade.pack.html?highlight=makecloud#yade._packSpheres.SpherePack.makeCloud -- You received this question notification because your team yade-users is an answer contact for Yade. ___ Mailing list: https://launchpad.net/~yade-users Post to : yade-users@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-users More help : https://help.launchpad.net/ListHelp
[Yade-users] [Question #291202]: Clumping - angl of repose
New question #291202 on Yade:
https://answers.launchpad.net/yade/+question/291202
Hi all,
In below code I have tried to study the effect of percentage/ratio of clumping
on repose angle. before adding the clumping section the scrip worked properly
however by adding clump grain do not fall down because of their gravity and the
sample explodes .
Would you please advise?
Thanks
#!/usr/bin/python
from yade import pack,utils, qt, plot
pred = pack.inAlignedBox((0,0,0),(14.5,14.5,14.5))
#create material
soil1 =
CohFrictMat(young=30e9,poisson=0.3,frictionAngle=radians(30),density=2600.0,normalCohesion=1e6,
shearCohesion=80e6,label='soil')
#color=(1,0,0) red color
#soil1 =
FrictMat(young=1e6,poisson=0.4,frictionAngle=radians(30),density=2500.0,label='soil')
O.materials.append(soil1)
O.bodies.append(utils.wall(0,axis=1,sense=1))
O.materials.append(CohFrictMat(young=30e9,poisson=0.3, frictionAngle =
radians(30) , label='wallmat'))
wallmat = O.materials[-1]
45
spheres=SpherePack()
spheres=pack.randomDensePack(pred,radius=.5,material='soil',spheresInCell=1000,color=(1,0,0),returnSpherePack=True)
spheres.toSimulation()
#O.bodies.append(spheres)
#
#
O.engines=[
ForceResetter(),#reset forces
InsertionSortCollider([Bo1_Wall_Aabb(),Bo1_Sphere_Aabb()]),
InteractionLoop(
[Ig2_Sphere_Sphere_ScGeom6D(),Ig2_Wall_Sphere_ScGeom()], # collision geometry
[Ip2_CohFrictMat_CohFrictMat_CohFrictPhys()], #
collision "physics"
[Law2_ScGeom6D_CohFrictPhys_CohesionMoment(),Law2_ScGeom_FrictPhys_CundallStrack()]
# contact law -- apply forces
),
# apply gravity force to particles
# damping: numerical dissipation of energy
NewtonIntegrator(damping=0.5,gravity=(0,-9.81,0)),
#qt.SnapshotEngine(fileBase='3d-',iterPeriod=200,label='snapshot'),
# this engine will be called after 2 steps, only once
PyRunner(command='checkUnbalanced()',realPeriod=200,label='checker'),
PyRunner(command='addPlotData()',iterPeriod=200)
]
#CLUMPING###
#create a box:
#id_box =
O.bodies.append(box((0,0,0),(.0045,0.0045,.0045),fixed=True,material=Mat))
#create assembly of spheres:
#sp=pack.SpherePack()
#sp.makeCloud((0,0,0),(.004,0.004,.004),rMean=.00018,rRelFuzz=.0001,num=1000,periodic=False)
#O.bodies.append([sphere(c,r,material=Mat) for c,r in sp])
#print len(sp),' particles generated.'
print 'Roundness coefficient without clumps is: ',O.bodies.getRoundness()
show how to use makeClumpTemplate():
#dyad:
#relRadList1 = [.0002,.0002]
#relPosList1 = [[.0003,0,0],[0.0006,0,0]]
#peanut:
relRadList2 = [.0002,0.0004,0.0002]
relPosList2 = [[0.0003,0,0],[0,0,0],[0.0006,0,0]]
#stick:
#relRadList3 = [1,1,1,1,1]
#relPosList3 = [[0,1,0],[0,2,0],[0,3,0],[0,4,0],[0,5,0]]
templates= []
#templates.append(clumpTemplate(relRadii=relRadList1,relPositions=relPosList1))
templates.append(clumpTemplate(relRadii=relRadList2,relPositions=relPosList2))
#templates.append(clumpTemplate(relRadii=relRadList3,relPositions=relPosList3))
show how to use replaceByClumps():
#replace by 50% dyads, 30% peanuts and 10% sticks:
#O.bodies.replaceByClumps(templates,[.5,.3,.1])
O.bodies.replaceByClumps(templates,[0.5])
show how to use getRoundness():
#create a list of all standalone spheres:
standaloneList = []
for b in O.bodies:
if b.isStandalone:
standaloneList.append(b.id)
print 'Roundness coefficient for spheres and clumps is:
',O.bodies.getRoundness()
print 'Roundness coefficient just for clumps is:
',O.bodies.getRoundness(standaloneList)
#sp.toSimulation()
print 'Number of elements: ', len(O.bodies)
print 'Box Volume: '
print 'Clumprepose,0.5,.25,30,3grain,0.5%'
O.trackEnergy=True
# set timestep to a fraction of the critical timestep
# the fraction is very small, so that the simulation is not too fast
# and the motion can be observed
O.dt=1*utils.PWaveTimeStep()
#makeVideo(snapshot.snapshots,'3d.mpeg',fps=10,bps=1)
# save the simulation, so that it can be reloaded later, for experimentation
#O.saveTmp()0
#checker.command='stopUnloading()'
def checkUnbalanced():
if unbalancedForce()<5e-2:
print('Reached target , stopping')
O.pause()
plot.saveDataTxt('Clumprepose,0.5,.5,30,3grain,0.5%.bz2')
plot.saveDataTxt('Clumprepose,0.5,.5,30,3grain,0.5%.txt')
#plot.saveDataTxt('modi.data.bz2')
# plot.saveGnuplot('bbb') is also possible
# collect history of data which will be plotted
def addPlotData():
# each item is given a names, by which it can be the unsed in plot.plots
# the **O.energy converts dictionary-like O.energy to plot.addData arguments
