yade-users team mailing list archive

[Huang peilun <question688275@xxxxxxxxxxxxxxxxxxxxx>]

Question #688275 on Yade changed:
https://answers.launchpad.net/yade/+question/688275

Description changed to:
I did a gravity deposition test in a cylinder. The following is the
original code and it works.

************************************************
from yade import pack

#material
SoilMat=FrictMat(young=25e6,poisson=0.2,density=2650,frictionAngle=0.28)
O.materials.append((SoilMat))

#define the chamber
O.bodies.append(geom.facetCylinder(center=(.5,.5,.5),radius=.5,height=1,wallMask=6,color=(1,0,0)))

#create foundation by making spheres in the cylinder.
sp=pack.SpherePack()
sp.makeCloud((0,0,0),(1,1,1),rMean=.05,rRelFuzz=.3)
cyl=pack.inCylinder((.5,.5,0),(.5,.5,1),.45)
sp=pack.filterSpherePack(cyl,sp,True)
sp.toSimulation(material=SoilMat)

O.engines=[
	ForceResetter(),
	InsertionSortCollider([Bo1_Sphere_Aabb(),Bo1_Facet_Aabb(),Bo1_Wall_Aabb()]),
	InteractionLoop(
		[Ig2_Sphere_Sphere_ScGeom(),Ig2_Facet_Sphere_ScGeom(),Ig2_Wall_Sphere_ScGeom()],
		[Ip2_FrictMat_FrictMat_FrictPhys()],
		[Law2_ScGeom_FrictPhys_CundallStrack()]
	),
	# update position using Newton's equations
	NewtonIntegrator(gravity=(0,0,-9.81),damping=0.05),
	# call the checkUnbalanced function (defined below) every 2 seconds
	PyRunner(command='checkUnbalanced()',realPeriod=2,label='checker'),
]
O.dt=.2*PWaveTimeStep()

def checkUnbalanced():
	print('%s: Unbalanced=%s' % (O.iter,unbalancedForce()))
	if O.iter<5000: return 
	if unbalancedForce()<.05: 
		O.pause()

O.saveTmp()
************************************************


However, when I magnify all units 1000 times, like the following code, some sphere just went through the bottom of the cylinder and I don't know why.


************************************************
from yade import pack

#material
SoilMat=FrictMat(young=25e6,poisson=0.2,density=2650,frictionAngle=0.28)
O.materials.append((SoilMat))

#define the chamber
O.bodies.append(geom.facetCylinder(center=(500,500,500),radius=500,height=1000,wallMask=6,color=(1,0,0)))

#create foundation by making spheres in the cylinder.
sp=pack.SpherePack()
sp.makeCloud((0,0,0),(1000,1000,1000),rMean=50,rRelFuzz=.3)
cyl=pack.inCylinder((500,500,0),(500,500,1000),450)
sp=pack.filterSpherePack(cyl,sp,True)
sp.toSimulation(material=SoilMat)

O.engines=[
	ForceResetter(),
	InsertionSortCollider([Bo1_Sphere_Aabb(),Bo1_Facet_Aabb(),Bo1_Wall_Aabb()]),
	InteractionLoop(
		[Ig2_Sphere_Sphere_ScGeom(),Ig2_Facet_Sphere_ScGeom(),Ig2_Wall_Sphere_ScGeom()],
		[Ip2_FrictMat_FrictMat_FrictPhys()],
		[Law2_ScGeom_FrictPhys_CundallStrack()]
	),
	# update position using Newton's equations
	NewtonIntegrator(gravity=(0,0,-9.81),damping=0.05),
	# call the checkUnbalanced function (defined below) every 2 seconds
	PyRunner(command='checkUnbalanced()',realPeriod=2,label='checker'),
]
O.dt=.2*PWaveTimeStep()

def checkUnbalanced():
	print('%s: Unbalanced=%s' % (O.iter,unbalancedForce()))
	if O.iter<5000: return 
	if unbalancedForce()<.05: 
		O.pause()

O.saveTmp()
************************************************


Thanks in advance!

-- 
You received this question notification because your team yade-users is
an answer contact for Yade.