Re: [Yade-users] [Question #611087]: I got a wrong damage ratio
Question #611087 on Yade changed:
https://answers.launchpad.net/yade/+question/611087
Status: Open => Answered
Robert Caulk proposed the following answer:
Hello Huihuang,
I recommend you read the final post of that thread more closely ;-). You
[i]want[/i] to initialize numBroCohBonds to zero each time, because each
time this function is called you are cycling through all of the
interactions and summing all the brokenbonds.
Maybe you misunderstood what I was recommending. Here it is:
def damageRatio():
global numBroCohBonds
numBroCohBonds=0
for br in O.interactions:
if br.phys.cohesionBroken==False:
continue
numBroCohBonds+=1 # calculate broken bonds
damageRatio=numBroCohBonds/float(sumCohBonds)
print sumCohBonds,numBroCohBonds
plot.saveDataTxt('data/damageratio.txt')
Best,
Robert
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Re: [Yade-users] [Question #611087]: I got a wrong damage ratio
Question #611087 on Yade changed: https://answers.launchpad.net/yade/+question/611087 Status: Answered => Open Huihuang Xia is still having a problem: Hi Robert, Thanks for your answer, but put the numBroCohBonds=0 inside the damageRatio() function is reallly a big mistake. You can refer to https://answers.launchpad.net/yade/+question/432617, in this question, it was stated that put the numBroCohBonds=0 inside the damageRatio() function led to a initialization of numBroCohBonds to zero each time. Damage ratio is the fraction of bonds broken relative to the total number of bonds originally created. In each time step, some new bonds broke, and number of bonds broken in damage ratio must be a sum of broken bonds in all time step before current time step. Thus, I still need an answer. Huihuang Xia -- 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 #612245]: Implementation of new contact law between particles
New question #612245 on Yade: https://answers.launchpad.net/yade/+question/612245 Hello Yade users, I try to implement a contact law with softening factor in the normal direction contact illustrated in the Figure 1 of the paper of Scholtes and Donze 2013 ( the paper can be downloaded from this link : https://filex.univ-lorraine.fr/get?k=afQQ74EoCQ5ZIy35Iz1). I implement this new contact in JointedCohesiveFrictionalPM.cpp from the line 153 to the line 163. JointedCohesiveFrictionalPM.cpp : https://filex.univ-lorraine.fr/get?k=KbdVLas2oIUUyKkG9nd JointedCohesiveFrictionalPM.hpp : https://filex.univ-lorraine.fr/get?k=Epw6QzDIm3HEjT9dH7d After the implementation, i simulate a trixial compression test and i obtain a strange stress/strain curves in the beginning of the simulation illustrated in the figure : https://filex.univ-lorraine.fr/get?k=dzDNhQKp3I5OXmaopWz I don't find the fault in the implementation. the script of the triaxial compression curves plotting : https://filex.univ-lorraine.fr/get?k=JVVacWCTBRjhLEpplth the script of the triaxial compression : https://filex.univ-lorraine.fr/get?k=BkLLO86ERwC6a3Cc35h the used sample : https://filex.univ-lorraine.fr/get?k=1UqqWzFs3tXJXhxZbVN Best regards. Jabrane. -- 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 #611087]: I got a wrong damage ratio
Question #611087 on Yade changed: https://answers.launchpad.net/yade/+question/611087 Status: Open => Answered Robert Caulk proposed the following answer: Hello, It looks like you are summing through broken bonds at each timestep and adding it to the sum from the previous step. If you want your damage ratio to be relative to each timestep, the number of broken bonds needs to be reset before each timestep. So I would put the numBroCohBonds=0 inside the damageRatio() function. This way,the summation is reset each time damageRatio() is called. Robert -- 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 #611087]: I got a wrong damage ratio
New question #611087 on Yade:
https://answers.launchpad.net/yade/+question/611087
Hi,
https://answers.launchpad.net/yade/+question/432617, in this question, damage
ratio was defined and implemented in YADE.
According to this definition, I built a impact crushing simulation using damage
ratio in YADE, but my code got a wrong result, as damage ratio in this
simulation was greater than 1.
Here is my code:
#!/usr/bin/python
# -*- coding: utf-8 -*-
#Created by Huihuang Xia from Huaqiao University,Xiamen,P.R.C
#My E-Mail:huihuang...@sina.com
###
# IMPORT MODULES
###
from yade import pack
from yade import plot
from yade import qt
###
# DEFINE MATERIALS
###
rock=CohFrictMat(young=5.98e7,poisson=0.3,alphaKr=3000,alphaKtw=3000,density=2678,frictionAngle=0.5,isCohesive=True,normalCohesion=7.9e6,shearCohesion=7.9e6,momentRotationLaw=True)
O.materials.append(rock)
steel=CohFrictMat(young=3.06e11,poisson=0.29,density=7861,frictionAngle=0.545,normalCohesion=0,shearCohesion=0)
O.materials.append(steel)
#
# CREATE SAMPLE & RIGID_WALL
#
wall=O.bodies.append(geom.facetBox(center=(0,0,0),extents=(0.015,0.015,0.0005),color=(1,1,0),material=steel,fixed=True))
pred=pack.inSphere(center=(0,0,0.006),radius=0.005)
assembly=pack.randomDensePack(pred,radius=0.0002,rRelFuzz=0.5,spheresInCell=2500,material=rock)
O.bodies.append(assembly)
for b in assembly:
b.state.vel=(0,0,-20)
###
# ENGINES
###
O.engines=[
ForceResetter(),
InsertionSortCollider([Bo1_Sphere_Aabb(aabbEnlargeFactor=1.0),Bo1_Facet_Aabb()]),
InteractionLoop(
[Ig2_Sphere_Sphere_ScGeom6D(interactionDetectionFactor=1.0),Ig2_Facet_Sphere_ScGeom6D()],
[Ip2_CohFrictMat_CohFrictMat_CohFrictPhys(setCohesionNow=True)],
[Law2_ScGeom6D_CohFrictPhys_CohesionMoment()]
),
VTKRecorder(fileName='post/impact-',recorders=['all'],iterPeriod=250),
GlobalStiffnessTimeStepper(active=1,timeStepUpdateInterval=5,timestepSafetyCoefficient=0.8,defaultDt=PWaveTimeStep()),
NewtonIntegrator(gravity=(0,0,-9.81)),
PyRunner(command='damageRatio()',realPeriod=5),
PyRunner(command='addPlotData()',realPeriod=5),
]
O.trackEnergy=True
O.step()
###
# DEFINE FUNCATIONS
###
#define a function to save damage ratio
global sumCohBonds
sumCohBonds=0
for b in O.interactions:
if b.phys.cohesionBroken==True:
continue
sumCohBonds+=1 # calculate total intact bonds
numBroCohBonds=0
def damageRatio():
global numBroCohBonds
for br in O.interactions:
if br.phys.cohesionBroken==False:
continue
numBroCohBonds+=1 # calculate broken bonds
damageRatio=numBroCohBonds/float(sumCohBonds)
print sumCohBonds,numBroCohBonds
plot.saveDataTxt('data/damageratio.txt')
def addPlotData():
damageRatio=numBroCohBonds/float(sumCohBonds)
plot.addData(t=O.time,dr=damageRatio)
plot.plots={'t':('dr')}
plot.plot()
#set an optimal timestep
O.dt=utils.PWaveTimeStep()
O.usesTimeStepper=True
#3D view and controller
qt.View()
qt.Controller()
and here is the damage ratio vs time:
# drt
0.0 9.49679622677e-09
0.0044209618287 1.60495856089e-06
0.0155272805693 4.9193404254e-06
0.0266335993099 8.39516779415e-06
0.0362303213284 1.10352770982e-05
0.047684063 1.44826140458e-05
0.0585507871469 1.73886336283e-05
0.0679318524908 2.02186788283e-05
0.0788225145568 2.3419099093e-05
0.091654086694 2.71228495603e-05
0.104485658831 3.03992441997e-05
0.117856372655 3.34097285591e-05
0.130687944792 3.48247511657e-05
0.144058658615 3.669561998e-05
0.158291999137 3.75218412351e-05
0.172633167997 3.86994439409e-05
0.190748328661 4.02569184773e-05
0.210696571059 4.18618769955e-05
0.236144058659 4.52902203506e-05
0.278089281863 4.98581792485e-05
0.339120120768 5.47350982335e-05
0.42009920207 5.83200136999e-05
0.520379555747 6.13408059573e-05
0.640931636834 6.41705226598e-05
0.776148371792 6.70709729927e-05
0.946409316368 7.14288492846e-05
1.15074401553 7.49846615977e-05
1.39076989433 7.87721800155e-05
1.673927108048.25338810098e-05
1.99611817986 8.60126620602e-05
2.32769031702 8.71703956744e-05
2.67360362303 8.81834109127e-05
3.04539573 9.07206891265e-05
3.46236791029 9.43729049081e-05
3.92160879879 9.80223033349e-05
4.41718783696 0.000101386989899
4.94899719646 0.000104757207048
5.50323485012 0.000107345725132
6.08561569981 0.000110695198656
6.67565236144 0.000111623153105
7.272697865 0.000112554955106
7.87524261376 0.000113345795924
8.48781539789 0.000116016886332
9.10739702394 0.000118131382236
9.72881173172 0.000120064040351
10.3572352814 0.00012179727
10.9897563080.000123849996843
