Re: [Yade-users] [Question #688195]: permeability model
Question #688195 on Yade changed:
https://answers.launchpad.net/yade/+question/688195
Description changed to:
Hello,
I'm trying to simulate 1-D flow through a cylindrical sphere packing
using the PFV model (FlowEngine) in Yade to mimic water flow through
porous concrete . So I want the spheres position to be fixed. I want to
impose a pressure on the top surface of the cylinder and get the flux at
the bottom surface. There should be no flux on the sides of the cylinder
(insulated, flow only in z direction). I have the following questions:
1- should the cylindrical sphere packing be inside a box? If I do the
simulation without the box I get a message like "Vh==NULL!! id=6
Point=0.08606 0.0994361 0.0201042 rad=0.0048993" which is repeated for
almost all body ids.
if the packing should be bounded by walls then I should have the packing
in a cylindrical wall, not in a box?
2- I don't know if my boundary conditions are correct for the case I'm trying
to model. based on my understanding from the Yade documentation:
flow.bndCondIsPressure=[Xmin,Xmax,Ymin,Ymax,Zmin,Zmax] is that accurate?
so if I want my packing to have pressure on the top surface I should
have: flow.bndCondIsPressure=[0,0,0,0,0,1]. Correct?
In my code below (which I wrote it based on the Oedometer code by B.
Chareyre), the reason I have my boundary like this:
flow.bndCondIsPressure=[0,0,0,0,1,1] is that in the documentation it
says: "bndCondIsPressure: defines the type of boundary condition for
each side. True if pressure is imposed, False for no-flux". So if I want
water to pass the bottom surface (zmin) and to get the flux at zmin I
think I should have zmin turned to 1 in the "flow.bndCondIsPressure
[]", correct?
I appreciate any help.
Thank you,
Othman
-
# -*- coding: utf-8 -*-
from yade import pack, ymport, plot
num_spheres=3000# number of spheres
young=1e6
radiuscyl=.05
heightcyl=.203
compFricDegree = 3 # initial contact friction during the confining phase
finalFricDegree = 30 # contact friction during the deviatoric loading
mn,mx=Vector3(0,0,0),Vector3(0.101,0.101,0.2035) # corners of the initial
packing
O.materials.append(FrictMat(young=young,poisson=0.5,frictionAngle=radians(compFricDegree),density=2600,label='spheres'))
O.materials.append(FrictMat(young=young,poisson=0.5,frictionAngle=0,density=0,label='walls'))
walls=aabbWalls([mn,mx],thickness=0,material='walls')
wallIds=O.bodies.append(walls)
sp=pack.SpherePack()
sp.makeCloud(mn,mx,rMean=0.0049,rRelFuzz=0.002,seed=1)
##
cylinder extraction
pred=pack.inCylinder((.05,.05,0),(.05,.05,heightcyl),radiuscyl)
spFilter=filterSpherePack(pred,sp,returnSpherePack=True)
spFilter.toSimulation(material='spheres')
yade.qt.View()
for i in O.bodies:
i.state.blockedDOFs='xyzXYZ'
O.engines=[
ForceResetter(),
InsertionSortCollider([Bo1_Sphere_Aabb(),Bo1_Box_Aabb()]),
InteractionLoop(
[Ig2_Sphere_Sphere_ScGeom(),Ig2_Box_Sphere_ScGeom()],
[Ip2_FrictMat_FrictMat_FrictPhys()],
[Law2_ScGeom_FrictPhys_CundallStrack()],label="iloop"
),
FlowEngine(dead=1,label="flow"),#introduced as a dead engine for the
moment, see 2nd section
GlobalStiffnessTimeStepper(active=1,timeStepUpdateInterval=100,timestepSafetyCoefficient=0.8),
NewtonIntegrator(damping=0.2)
]
flow.dead=0
flow.defTolerance=0.3
flow.meshUpdateInterval=200
flow.useSolver=3
flow.permeabilityFactor=1
flow.viscosity=10
flow.bndCondIsPressure=[0,0,0,0,1,1]
flow.bndCondValue=[0,0,0,0,0,10]
flow.boundaryUseMaxMin=[0,0,0,0,1,1]
O.dt=0.1e-3
O.dynDt=False
O.run(1,1)
Qin = flow.getBoundaryFlux(5)# 5 is top wall
Qout = flow.getBoundaryFlux(4)
Qxmin=flow.getBoundaryFlux(0)
Qxmax=flow.getBoundaryFlux(1)
Qymin=flow.getBoundaryFlux(2)
Qymax=flow.getBoundaryFlux(3)
NewtonIntegrator(damping=0)
O.engines=O.engines+[PyRunner(iterPeriod=200,command='history()',label='recorder')]
## a function saving variables
def history():
plot.addData(Qin=Qin,Qout=Qout,t=O.time,p=flow.averagePressure(),Qxmin=Qxmin,Qxmax=Qxmax,Qymin=Qymin,Qymax=Qymax)
plot.saveDataTxt('1.txt')
plot.plots={'t':('p')}
plot.plot()
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Re: [Yade-users] [Question #688156]: How to create a regular prism in Yade
Question #688156 on Yade changed: https://answers.launchpad.net/yade/+question/688156 Status: Answered => Solved Huang peilun confirmed that the question is solved: Thank you, Jan! I'll do better next time. -- 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 #688174]: Definition of table with zeros arrays
Question #688174 on Yade changed: https://answers.launchpad.net/yade/+question/688174 ladynelsonchildcare posted a new comment: Hi, I also have the same question and find the solution.https://ladynelsonchildcare.com.au/;>early learning -- 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 #688174]: Definition of table with zeros arrays
Question #688174 on Yade changed: https://answers.launchpad.net/yade/+question/688174 paintball chice posted a new comment: I also agree with Robert. Thanks Robert and Przemek. Here see that: https://paintballchoice.com/barrel/ -- 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 #688203]: Simulation blocked after O.run in a conditional translation motion
Question #688203 on Yade changed:
https://answers.launchpad.net/yade/+question/688203
Status: Needs information => Open
Rioual gave more information on the question:
...Here is the code:
#Start
import time
from yade import qt
from yade import ymport
#Import packing in the cylinder from prepare-packing.py
O.load('init_Final_state_packing.yade')
###
## PhysicalParameters
Density=2400
frictionAngle=radians(35)
tc = 0.001
en = 0.05
et = 0.05
## Import wall's geometry
facetMat=O.materials.append(ViscElMat(frictionAngle=frictionAngle,tc=tc, en=en,
et=et)) # **params sets kn, cn, ks, cs
sphereMat=O.materials.append(ViscElMat(density=Density,frictionAngle=frictionAngle,tc=tc,en=en,et=et))
from yade import ymport
#**
global TransEngload2
#**
# Importation de la roue Warren-Spring
global fctIdsWS
fctIdsWS=O.bodies.append(ymport.stl('WS-FR-1.stl',color=(1,0,0),material=facetMat))
#fctIdscylinder=O.bodies.append(ymport.stl('PotN.stl',color=(1,0,0),material=facetMat))
## Timestep
O.dt=.2*tc
## Engines
O.engines=[
## Resets forces and momenta the act on bodies
ForceResetter(),
## Associates bounding volume to each body.
#BoundDispatcher([Bo1_Sphere_Aabb(),Bo1_Facet_Aabb()]),
## Using bounding boxes find possible body collisions.
#InsertionSortCollider(),
InsertionSortCollider([Bo1_Sphere_Aabb(),Bo1_Facet_Aabb()]),
## Interactions
InteractionLoop(
# the loading plate is a facet, we need to handle
sphere+sphere, sphere+facet
[Ig2_Sphere_Sphere_ScGeom(),Ig2_Facet_Sphere_ScGeom(),Ig2_Wall_Sphere_ScGeom()],
[Ip2_FrictMat_FrictMat_FrictPhys()],
[Law2_ScGeom_FrictPhys_CundallStrack()]
),
## Apply gravity
GravityEngine(gravity=[0,0,-9.81]),
## Cundall damping must been disabled!
NewtonIntegrator(damping=0),
## Apply kinematics to wheel
PyRunner(command='kinematics_WS()',realPeriod=1,label='kine'),
]
from yade import qt
qt.View()
def kinematics_WS():
h_WS = calc_h()[0]
hmaxSpheres = calc_h()[1]
print 'test0','h_WS=',h_WS,'hmaxSpheres=',hmaxSpheres
TransEngload2 =
TranslationEngine(ids=fctIdsWS,translationAxis=[0,-1,0],velocity=10)
O.engines=O.engines+[TransEngload2]
while h_WS > hmaxSpheres:
print 'test01'
TransEngload2.dead = False
print 'test02'
O.run(1,True)
# O.engines=O.engines+[PyRunner(command='calc_h()')]
print 'test03'
h_WS = calc_h()[0]
hmaxSpheres = calc_h()[1]
print 'test1','h_WS=',h_WS,'hmaxSpheres=',hmaxSpheres
TransEngload2.dead = True
else:
amTOT = sum((O.bodies[facetid].state.angMom)[1] for
facetid in fctIdsWS)
while (amTOT< 1e-10):
O.engines=O.engines+[PyRunner(command='addTorque()',iterPeriod=1)]
amTOT = sum((O.bodies[facetid].state.angMom)[1] for
facetid in fctIdsWS)
else:
# Stop simulation et measurement of the shear torque and cohesion
C_WS = 3* (imposed_T)/(2*Pi*(R0^3-R1^3))
print 'C_WS=',C_WS
print 'End of the calculation for
Cohesion***' #
O.pause()
#*
#This function calculate the height of the boundary h_WS and the maximum height
of the packing hmax_Spheres
def calc_h():
###
#Calculate h_WS
minY = 1e99
maxY = -1e99
for facet in fctIdsWS:
# print 'facet=', facet
facet= O.bodies[facet]
vs = [facet.state.pos + facet.state.ori * v for v in
facet.shape.vertices] # vertices in global coord system
# print 'vs=',vs
minY = min(minY,min(v[1] for v in vs))
maxY = max(maxY,max(v[1] for v in vs)) ###
# print 'maxY=',maxY,'minY=',minY
h_WS = maxY
###
#Calculate hmax_Spheres
idHMax=0# on definit une variable pour
identifier quel corps a la hauteur la plus haute
hMax=0.0# initialisation de la hauteur
a zero
for i in O.bodies: # on parcours tout les corps du
systeme
h=i.state.pos[1]# on extrait la position selon
l'axe y
if (type(i.shape).__name__ == 'Sphere' and h>hMax): #si le
solide est une sphere et sa position est plus haut
Re: [Yade-users] [Question #688203]: Simulation blocked after O.run in a conditional translation motion
Question #688203 on Yade changed: https://answers.launchpad.net/yade/+question/688203 Status: Open => Needs information Jan Stránský requested more information: Hello, please provide a complete script [1], otherwise the best we can do is guessing.. thanks Jan [1] https://www.yade-dem.org/wiki/Howtoask -- 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 #688203]: Simulation blocked after O.run in a conditional translation motion
New question #688203 on Yade: https://answers.launchpad.net/yade/+question/688203 Hello, This mistake may be obvious but I can't get it. I am studying the translation motion of a boundary WS (using TranslationEngine) as long as an conditional statement is fulfilled (the height of the boundary h_WS must be smaller than the maximum height of the packing hmaxSpheres). I use O.run(1,True) to let the engine work for one time step but the simulation seems to be frozen at the "O.run(1,True)" statement. [... PyRunner(command='kinematics_WS()',realPeriod=1,label='kine'), ... ] def kinematics_WS(): h_WS = calc_h()[0] hmaxSpheres = calc_h()[1] print 'test0','h_WS=',h_WS,'hmaxSpheres=',hmaxSpheres TransEngload2 = TranslationEngine(ids=fctIdsWS,translationAxis=[0,-1,0],velocity=10) O.engines=O.engines+[TransEngload2] while h_WS > hmaxSpheres: print 'test01' TransEngload2.dead = False print 'test02' O.run(1,True) ***frozen here!*** # O.engines=O.engines+[PyRunner(command='calc_h()')] print 'test03' h_WS = calc_h()[0] hmaxSpheres = calc_h()[1] print 'test1','h_WS=',h_WS,'hmaxSpheres=',hmaxSpheres TransEngload2.dead = True else: . Output: test0 h_WS= 130.0 hmaxSpheres= 100.369406791 test01 test02 ...frozen The boundary does not seem to move even if i put a higher step number in O.run() * Thank you for your Help, Best Vincent -- 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 #688156]: How to create a regular prism in Yade
Question #688156 on Yade changed: https://answers.launchpad.net/yade/+question/688156 Jan Stránský proposed the following answer: > Here's another question in that case, next time please open a new question [1] > I want ... this cylinder ... have contact with spheres, what kind of IGeomFunctor and LawFunctor should I use? that is the point, currently there is none.. Use an approximation of cylinder made of facets or boxes (for facets there is facetCylinder function [2]) cheers Jan [1] https://www.yade-dem.org/wiki/Howtoask [2] https://yade-dem.org/doc/yade.geom.html#yade.geom.facetCylinder -- 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 #688156]: How to create a regular prism in Yade
Question #688156 on Yade changed: https://answers.launchpad.net/yade/+question/688156 Huang peilun posted a new comment: Thank you, Jan! That solved my problem. I'll post what I have tried and why/how it went wrong. This time I just use O.bodies.append(Cylinder(length=1, radius=1)) I didn't figure out what type does the Cylinder class have. I want to make a penetration test, and I want a cylinder shaped rod to do this. Here's another question, I want to apply gravity to this cylinder and have contact with spheres, what kind of IGeomFunctor and LawFunctor should I use? Now the current script is as followed. The cylinder just disappeared at the beginning of the simulation. from yade import pack O.bodies.append(geom.facetBox((.5,.5,.5),(.5,.5,.5),wallMask=31)) rod=Body() rod.shape=Cylinder() rod.shape.length=.5 rod.shape.radius=.2 rod.state.pos=(.5,.5,1.8) O.bodies.append(rod) sp=pack.SpherePack() sp.makeCloud((0,0,0),(1,1,1),rMean=.05,rRelFuzz=.3) sp.toSimulation() O.engines=[ ForceResetter(), InsertionSortCollider([Bo1_Sphere_Aabb(),Bo1_Cylinder_Aabb(),Bo1_Facet_Aabb()]), InteractionLoop( [Ig2_Sphere_Sphere_ScGeom(),Ig2_Facet_Sphere_ScGeom(),Ig2_Sphere_ChainedCylinder_CylScGeom()], [Ip2_FrictMat_FrictMat_FrictPhys()], [Law2_ScGeom_FrictPhys_CundallStrack(),Law2_CylScGeom_FrictPhys_CundallStrack()] ), # update position using Newton's equations NewtonIntegrator(gravity=(0,0,-9.81),damping=0.4), # call the checkUnbalanced function (defined below) every 2 seconds PyRunner(command='checkUnbalanced()',realPeriod=2), ] O.dt=.2*PWaveTimeStep() def checkUnbalanced(): if O.forces.f(rod.id)[2]==0: return ball.state.blockedDOFs='xyXYZ' ball.state.vel=(0,0,2) if unbalancedForce()<.05: O.pause() O.saveTmp() Thanks! -- 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 #688156]: How to create a regular prism in Yade
Question #688156 on Yade changed: https://answers.launchpad.net/yade/+question/688156 Status: Needs information => Answered Jan Stránský proposed the following answer: > I want to create a body shaped as a prism. use box [1] > I tried couple of times, I can't create a body shaped as a cylinder by this class. next time please post also what you have tried and why/how it went wrong. E.g. you can try something like: ### b=Body() b.shape=Cylinder() b.shape.length=1 b.shape.radius=1 O.bodies.append(b) ### What do you want to do with the cylinder? just that Yade currently (AFAIK) is not able to work reasonably with "pure" cylinders.. cheers Jan [1] https://yade-dem.org/doc/yade.utils.html#yade.utils.box -- 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 #688156]: How to create a regular prism in Yade
Question #688156 on Yade changed: https://answers.launchpad.net/yade/+question/688156 Huang peilun posted a new comment: I want to create a body shaped as a prism. By "not round cylinder" I mean not the cylinder for yade.gridpfacet module, I see from the yade book that there is a class yade.wrapper.Cylinder. However, I tried couple of times, I can't create a body shaped as a cylinder by this class. Thanks. -- 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 #687836]: Is there a way to assign joint properties to a pack of clumps but not using the JCfpm material?
Question #687836 on Yade changed: https://answers.launchpad.net/yade/+question/687836 Status: Needs information => Expired Launchpad Janitor expired the question: This question was expired because it remained in the 'Needs information' state without activity for the last 15 days. -- 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 #688197]: Shear loading
Question #688197 on Yade changed: https://answers.launchpad.net/yade/+question/688197 Status: Open => Answered Jan Stránský proposed the following answer: Hello, > uniaxial force usually it is called normal (force, direction, component...) rather than uniaxial 1) because Ig2_Sphere_Sphere_ScGeom computes normal force according to penetration depth, which is penetrationDepth = radius1 + radius2 - distanceOfCenters and since distance of centers changes, penetrationDepth and thus normal force changes 3+4) your Matlab model is probably "more simple" (does not take into account the actual centers' distance, only its normal projection), basically based on different assumptions/formulation. Therefore you get different results. > I read [1], but I want something with more detail. read not only a short part, but rather the whole section Kinematic variables [3]. IMO there is enough details. I am not sure if some papers give more details. Anyway, the source code is the best source how to investigate what really is computed :-) normal component [4] and shear components [5] (not only the referenced line, but also the code around). cheers Jan [3] https://yade-dem.org/doc/formulation.html#kinematic-variables [4] https://gitlab.com/yade-dev/trunk/blob/master/pkg/dem/Ig2_Sphere_Sphere_ScGeom.cpp#L39 [5] https://gitlab.com/yade-dev/trunk/blob/master/pkg/dem/ScGeom.cpp#L52 -- 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
