yade-users team mailing list archive

[Clinton Schramm <question294531@xxxxxxxxxxxxxxxxxxxxx>]

Question #294531 on Yade changed:
https://answers.launchpad.net/yade/+question/294531

    Status: Answered => Open

Clinton Schramm is still having a problem:
Hi Jan

Thanks for the prompt reply. I have already placed the code within
Pyrunner, and still get the same results. I'll post my code below (it is
just a modified Odometer Example code with the change sphere colour).
Can you see any reason why it shouldn't be working?


# load parameters from file if run in batch
# default values are used if not run from batch
readParamsFromTable(rMean=.05,rRelFuzz=.3,maxLoad=1e6,minLoad=1e4)
# make rMean, rRelFuzz, maxLoad accessible directly as variables later
from yade.params.table import *

# create box with free top, and ceate loose packing inside the box
from yade import pack, plot
O.bodies.append(geom.facetBox((.5,.5,.5),(.5,.5,.5),wallMask=31))
sp=pack.SpherePack()
sp.makeCloud((0,0,0),(1,1,1),rMean=rMean,rRelFuzz=rRelFuzz)
sp.toSimulation()

O.engines=[
   ForceResetter(),
   # sphere, facet, wall
   InsertionSortCollider([Bo1_Sphere_Aabb(),Bo1_Facet_Aabb(),Bo1_Wall_Aabb()]),
   InteractionLoop(
      # the loading plate is a wall, we need to handle sphere+sphere, sphere+facet, sphere+wall
      [Ig2_Sphere_Sphere_L3Geom(),Ig2_Facet_Sphere_L3Geom(),Ig2_Wall_Sphere_L3Geom()],
      [Ip2_FrictMat_FrictMat_FrictPhys()],
      [Law2_L3Geom_FrictPhys_ElPerfPl()]
   ),
   NewtonIntegrator(gravity=(0,0,-9.81),damping=0.5),
   # the label creates an automatic variable referring to this engine
   # we use it below to change its attributes from the functions called
   PyRunner(command='checkUnbalanced()',realPeriod=2,label='checker'),
]
O.dt=.5*PWaveTimeStep()

# the following checkUnbalanced, unloadPlate and stopUnloading functions are all called by the 'checker'
# (the last engine) one after another; this sequence defines progression of different stages of the
# simulation, as each of the functions, when the condition is satisfied, updates 'checker' to call
# the next function when it is run from within the simulation next time

# check whether the gravity deposition has already finished
# if so, add wall on the top of the packing and start the oedometric test
def checkUnbalanced():
   # at the very start, unbalanced force can be low as there is only few contacts, but it does not mean the packing is stable
   if O.iter<5000: return 
   # the rest will be run only if unbalanced is < .1 (stabilized packing)
   if unbalancedForce()>.1: return 
   # add plate at the position on the top of the packing
   # the maximum finds the z-coordinate of the top of the topmost particle
   for s in O.bodies
		s.shape.color=scalarOnColorScale(s.state.displ().norm(),0,1)
		print 0.1*s.state.displ() #Check to see if repeating
   O.bodies.append(wall(max([b.state.pos[2]+b.shape.radius for b in O.bodies if isinstance(b.shape,Sphere)]),axis=2,sense=-1))
   global plate        # without this line, the plate variable would only exist inside this function
   plate=O.bodies[-1]  # the last particles is the plate
   # Wall objects are "fixed" by default, i.e. not subject to forces
   # prescribing a velocity will therefore make it move at constant velocity (downwards)
   plate.state.vel=(0,0,-.1)
   # start plotting the data now, it was not interesting before
   O.engines=O.engines+[PyRunner(command='addPlotData()',iterPeriod=200)]
   # next time, do not call this function anymore, but the next one (unloadPlate) instead
   checker.command='unloadPlate()'

def unloadPlate():
   # if the force on plate exceeds maximum load, start unloading
   if abs(O.forces.f(plate.id)[2])>maxLoad:
      plate.state.vel*=-1
      # next time, do not call this function anymore, but the next one (stopUnloading) instead
      checker.command='stopUnloading()'

def stopUnloading():
   if abs(O.forces.f(plate.id)[2])<minLoad:
      # O.tags can be used to retrieve unique identifiers of the simulation
      # if running in batch, subsequent simulation would overwrite each other's output files otherwise
      # d (or description) is simulation description (composed of parameter values)
      # while the id is composed of time and process number
      plot.saveDataTxt(O.tags['d.id']+'.txt')
      O.pause()
   
def addPlotData():
   if not isinstance(O.bodies[-1].shape,Wall):
      plot.addData(); return
   Fz=O.forces.f(plate.id)[2]
   plot.addData(Fz=Fz,w=plate.state.pos[2]-plate.state.refPos[2],unbalanced=unbalancedForce(),i=O.iter)

# besides unbalanced force evolution, also plot the displacement-force diagram
plot.plots={'i':('unbalanced',),'w':('Fz',)}
plot.plot()

O.run()

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