yade-users team mailing list archive

[Huan <question706562@xxxxxxxxxxxxxxxxxxxxx>]

New question #706562 on Yade:
https://answers.launchpad.net/yade/+question/706562

Hello,

I am confuse by the Oedometric test provided in the example: 
https://yade-dem.org/doc/tutorial-examples.html?highlight=oedometric
I don't understand where the max and min load come. I was able to add the test to my experiment, but I decided to remove it first because after the compression the sphere would be directly bounce off through the plate.


Following is my current code:

import random
import math
from yade import geom, pack, utils, plot, ymport
import pandas as pd

# Define material properties
youngModulus = 1e7
poissonRatio = 0.25
density = 2000

# Create material
material = O.materials.append(FrictMat(young=youngModulus, poisson=poissonRatio, density=density))

# Define cylinder with funnel parameters
center = (0, 0, 0)
diameter = 0.102
height = 0.18

# create cylindrical body with radius 0.102 m and height 0.064 m
cylinder = geom.facetCylinder(center=center, radius=diameter/2, height=height, segmentsNumber=80, wallMask=6)

# assign material to each body in the cylinder
for body in cylinder:
    body.bodyMat = material

# add cylinder to simulation
O.bodies.append(cylinder)

# Define cylinder with funnel parameters
center1 = (0,0,height/2)
dBunker = 0.4
dOutput = 0.102
hBunker = 0
hOutput = 0.15
hPipe = 0

# create funnel as a bunker with diameter 0.102 m, height 0.064 m
funnel = geom.facetBunker(center=center1, dBunker=dBunker, dOutput=dOutput, hBunker=hBunker,hOutput=hOutput, hPipe=hPipe, segmentsNumber=80, wallMask=4)

# assign material to each body in the funnel
for body in funnel:
    body.bodyMat = material

# add funnel to simulation
O.bodies.append(funnel)

# define sphere parameters and number of spheres
rMean1 = (0.0125+0.019)/4
rRelFuzz1 = (0.019-0.0125)/4/rMean1
num1 = 28
rMean2 = (0.0095+0.0125)/4
rRelFuzz2 = (0.0125-0.0095)/4/rMean2
num2 = 86
rMean3 = (0.00475+0.0095)/4
rRelFuzz3 = (0.0095-0.00475)/4/rMean3
num3 = 2071
rMean4 = (0.00236+0.00475)/4
rRelFuzz4 = (0.00475-0.00236)/4/rMean4
num4 = 18997

#create empty sphere packing
sp = pack.SpherePack()

# generate randomly sphere
sp.makeCloud((-dBunker/4,-dBunker/4,1.3*height),(dBunker/4,dBunker/4,2*height), rMean = rMean1, rRelFuzz = rRelFuzz1, num = num1)
sp.makeCloud((-dBunker/4,-dBunker/4,1.3*height),(dBunker/4,dBunker/4,2*height), rMean = rMean2, rRelFuzz = rRelFuzz2, num = num2)
sp.makeCloud((-dBunker/4,-dBunker/4,1.3*height),(dBunker/4,dBunker/4,2*height), rMean = rMean3, rRelFuzz = rRelFuzz3, num = num3)
sp.makeCloud((-dBunker/4,-dBunker/4,1.3*height),(dBunker/4,dBunker/4,2*height), rMean = rMean4, rRelFuzz = rRelFuzz4, num = num4)

# add the sphere pack to the simulation
sp.toSimulation(material = material)

for body in O.bodies:
   if not isinstance(body.shape, Sphere): 
       continue
   if body.shape.radius == rRelFuzz1: #SP
       body.shape.color = (0,0,1) #blue
   if body.shape.radius == rRelFuzz2: #SP1
       body.shape.color = (1,0,0) #red
   if body.shape.radius == rRelFuzz3: #SP2
       body.shape.color = (0,1,0) #green
   if body.shape.radius == rRelFuzz4: #SP3
       body.shape.color = (1,1,0) #yellow

O.engines = [
        ForceResetter(),
        InsertionSortCollider([Bo1_Sphere_Aabb(), Bo1_Facet_Aabb()]),
        InteractionLoop(
                # handle sphere+sphere and facet+sphere collisions
                [Ig2_Sphere_Sphere_ScGeom(), Ig2_Facet_Sphere_ScGeom()],
                [Ip2_FrictMat_FrictMat_FrictPhys()],
                [Law2_ScGeom_FrictPhys_CundallStrack()]
        ),
        NewtonIntegrator(gravity=(0, 0, -9.81), damping=0.4),
        # call the checkUnbalanced function (defined below) every 2 seconds
        PyRunner(command='checkUnbalanced()', realPeriod=2),
        # call the addPlotData function every 200 steps
        PyRunner(command='addPlotData()', iterPeriod=100)
]
O.dt = .5 * PWaveTimeStep()

# enable energy tracking; any simulation parts supporting it
# can create and update arbitrary energy types, which can be
# accessed as O.energy['energyName'] subsequently
O.trackEnergy = True


# if the unbalanced forces goes below .05, the packing
# is considered stabilized, therefore we stop collected
# data history and stop
def checkUnbalanced():
	if unbalancedForce() < 1e-2:
		O.pause()
		plot.saveDataTxt('bbb.txt.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
	plot.addData(i=O.iter, unbalanced=unbalancedForce(), **O.energy)


# define how to plot data: 'i' (step number) on the x-axis, unbalanced force
# on the left y-axis, all energies on the right y-axis
# (O.energy.keys is function which will be called to get all defined energies)
# None separates left and right y-axis
plot.plots = {'i': ('unbalanced', None, O.energy.keys)}

# show the plot on the screen, and update while the simulation runs
plot.plot()

O.saveTmp()

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