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[SayedHessam <question669048@xxxxxxxxxxxxxxxxxxxxx>]

Question #669048 on Yade changed:
https://answers.launchpad.net/yade/+question/669048

SayedHessam posted a new comment:
Dear Robert,

Sorry for the lack of information.
BTW, you can find herewith my script, as you requested:


############################
###   DEFINING ENGINES   ###
############################

triax=TriaxialStressController(
	## TriaxialStressController will be used to control stress and strain. It controls particles size and plates positions.
	## this control of boundary conditions was used for instance in http://dx.doi.org/10.1016/j.ijengsci.2008.07.002
	maxMultiplier=1.+2e4/young, # spheres growing factor (fast growth)
	finalMaxMultiplier=1.+2e3/young, # spheres growing factor (slow growth)
	thickness = 0,
	## switch stress/strain control using a bitmask. What is a bitmask, huh?!
	## Say x=1 if stess is controlled on x, else x=0. Same for for y and z, which are 1 or 0.
	## Then an integer uniquely defining the combination of all these tests is: mask = x*1 + y*2 + z*4
	## to put it differently, the mask is the integer whose binary representation is xyz, i.e.
	## "100" (1) means "x", "110" (3) means "x and y", "111" (7) means "x and y and z", etc.
	stressMask = 7,
	internalCompaction=True, # If true the confining pressure is generated by growing particles
)

newton=NewtonIntegrator(damping=damp)

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()]
	),
	## We will use the global stiffness of each body to determine an optimal timestep (see https://yade-dem.org/w/images/1/1b/Chareyre&Villard2005_licensed.pdf)
	FlowEngine(dead=1,label="flow"),#introduced as a dead engine for the moment, see 2nd section
	GlobalStiffnessTimeStepper(active=1,timeStepUpdateInterval=100,timestepSafetyCoefficient=0.8),
	triax,
	TriaxialStateRecorder(iterPeriod=100,file='WallStresses'+table.key),
	newton
]

#Display spheres with 2 colors for seeing rotations better
Gl1_Sphere.stripes=0
if nRead==0: yade.qt.Controller(), yade.qt.View()

## UNCOMMENT THE FOLLOWING SECTIONS ONE BY ONE
## DEPENDING ON YOUR EDITOR, IT COULD BE DONE
## BY SELECTING THE CODE BLOCKS BETWEEN THE SUBTITLES
## AND PRESSING CTRL+SHIFT+D

#######################################
###   APPLYING CONFINING PRESSURE   ###
#######################################

#the value of (isotropic) confining stress defines the target stress to be applied in all three directions
triax.goal1=triax.goal2=triax.goal3=-10000

while 1:
  O.run(1000, True)
  #the global unbalanced force on dynamic bodies, thus excluding boundaries, which are not at equilibrium
  unb=unbalancedForce()
  print 'unbalanced force:',unb,' mean stress: ',triax.meanStress
  if unb<stabilityThreshold and abs(-10000-triax.meanStress)/10000<0.001:
    break

O.save('confinedState'+key+'.yade.gz')
print "###      Isotropic state saved      ###"
print triax.porosity
print triax.meanStress
print len(O.bodies)

#####################################################
###    Example of how to record and plot data     ###
#####################################################

from yade import plot

## a function saving variables
def history():
  	plot.addData(unbalanced=unbalancedForce(),e11=-triax.strain[0], e22=-triax.strain[1], e33=-triax.strain[2],
        ev=-triax.strain[0]-triax.strain[1]-triax.strain[2],
      s11=-triax.stress(triax.wall_right_id)[0],
      s22=-triax.stress(triax.wall_top_id)[1],
      s33=-triax.stress(triax.wall_front_id)[2],
                    devi = -triax.stress(triax.wall_top_id)[1] - (-triax.stress(triax.wall_right_id)[0]-triax.stress(triax.wall_front_id)[2]) / 2.0,
                    p = triax.meanStress,
		    i=O.iter)

if 1:
  # include a periodic engine calling that function in the simulation loop
  O.engines=O.engines[0:5]+[PyRunner(iterPeriod=20,command='history()',label='recorder')]+O.engines[5:7]
  #O.engines.insert(4,PyRunner(iterPeriod=20,command='history()',label='recorder'))
else:
  # With the line above, we are recording some variables twice. We could in fact replace the previous
  # TriaxialRecorder
  # by our periodic engine. Uncomment the following line:
  O.engines[4]=PyRunner(iterPeriod=20,command='history()',label='recorder')

O.run(100,True)

## declare what is to plot. "None" is for separating y and y2 axis
plot.plots={'i':('e11','e22','e33',None,'s11','s22','s33')}
## the traditional triaxial curves would be more like this:
#plot.plots={'e22':('s11','s22','s33',None,'ev')}

# display on the screen (doesn't work on VMware image it seems)
plot.plot()

devi_test = -triax.stress(triax.wall_top_id)[1] -
(-triax.stress(triax.wall_right_id)[0]-triax.stress(triax.wall_front_id)[2])
/ 2.0

def stress_control1():
  global devi_test
  while devi_test < 50000:
     O.run(100)
     devi_test = -triax.stress(triax.wall_top_id)[1] - (-triax.stress(triax.wall_right_id)[0]\
     -triax.stress(triax.wall_front_id)[2]) / 2.0

def stress_control2():
  global devi_test
  while devi_test > -50000:
     O.run(100)
     devi_test = -triax.stress(triax.wall_top_id)[1] - (-triax.stress(triax.wall_right_id)[0]\
     -triax.stress(triax.wall_front_id)[2]) / 2.0

#B. Activate flow engine and set boundary conditions in order to get permeability
flow.dead=0
flow.defTolerance=0.3
flow.meshUpdateInterval=200
flow.useSolver=3
flow.permeabilityFactor=1
flow.viscosity=1.3e-3
flow.fluidBulkModulus = 2e9
flow.imposePressure(Vector3(triax.width/2,triax.height/2,triax.depth/2),0.001)
flow.bndCondIsPressure=[0,0,0,0,0,0]
flow.bndCondValue=[0,0,0,0,0,0]
flow.boundaryUseMaxMin=[0,0,0,0,0,0]
O.dt=0.1e-3
O.dynDt=False

O.run(1,1)
Qin = flow.getBoundaryFlux(2)
Qout = flow.getBoundaryFlux(3)
tic_toc = 0
print(O.iter)
print(triax.stressMask)
print(triax.goal1)
print(triax.goal2)
print(triax.goal3)

Regards
Sam

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