Assessing aperture size while injectin in a joint plane

Hi Yousef,

2 ways:

1) record the positions of particles located on each side of the joint
2)record the aperture of the interactions labelled "onJoint" (https://yade-dem.org/doc/yade.wrapper.html?highlight=jointaperture#yade.wrapper.JCFpmPhys.crackJointAperture)

I would suggest option 2) if you use the neverErase=True which keep track of the interactions during the duration of the simulation. To do so, you could (this is just one possibility from someone who is not very good at programming):

1) create a list containing all interactions "onJoint". You can do that right after the firts timestep byt looping over all interactions, checking for those which are "onJoint":

intOnFracPlane=[]
for i in O.interactions:
  if i.phys.isOnJoint:
    intOnFracPlane.append(i)

2) record their aperture "periodically " during the simulation with a dedicated fonction that you would call every n iterations like:

def recordInteractionStatus():
  global intOnFracPlane
  inFile=open('interactions_timePositionsAperturePressure_'+str(O.iter)+'_'+str(round(O.time,3)),'a')
  for i in intOnFracPlane:
    inFile.write( str(i.geom.contactPoint[0]) + '\t' + str(i.geom.contactPoint[1]) + '\t' + str(i.geom.contactPoint[2]) + '\t' + str(i.phys.crackJointAperture) + '\t' + str(flow.getPorePressure((i.geom.contactPoint[0],i.geom.contactPoint[1],i.geom.contactPoint[2]))) + '\n')
  inFile.close()

Doing so, you will get several text files with the information you want and you'll then be able to map the evolution of the aperture over all the joint surface.

I guess you could also adapt these lines to get some sort of average value (probably not meaningful though) or, another option, the aperture at a given location (e.g., injection point).

Luc

Hi Luc,

Thanks a lot. The code works fine and I am really appreciated you help me with that. It just needed a tiny change in the lines.

#####

 def recordInteractionStatus():
 global intOnFracPlane
 intOnFracPlane=[]
 for i in O.interactions:
  if i.phys.isOnJoint:
   intOnFracPlane.append(i)
 inFile=open('interactions_timePositionsAperturePressure_'+str(O.iter)+'_'+str(round(O.time,3)),'a')
 for i in intOnFracPlane:
  inFile.write( str(i.geom.contactPoint[0]) + '\t' + str(i.geom.contactPoint[1]) + '\t' + str(i.geom.contactPoint[2]) + '\t' + str(i.phys.crackJointAperture) + '\t' + str(flow.getPorePressure((i.geom.contactPoint[0],i.geom.contactPoint[1],i.geom.contactPoint[2]))) + '\n')
 inFile.close()

#####

Best regards,
Yousef

Thanks Luc Scholtès, that solved my question.

Hi Luc,

Could you please inform me how to obtain aperture at a given point (for instance injection point).

Should I have the cell IDs of that point or is it possible to do it by defining the coordinates of that point?

Thanks in advance for your time and help.

Best regards,
Yousef

Many thanks for your swift response Luc.

Cheers,
Yousef

Thanks Luc Scholtès, that solved my question.

Something like this should work to identify the interactions on the whole joint and the one at the injection point Xp:

intOnFracPlane=[]
intOnInjPoint=[]
for i in O.interactions:
  if i.phys.isOnJoint:
    intOnFracPlane.append(i)
    if (i.geom.contactPoint[0]>(Xp[0]-Rmin)) and (i.geom.contactPoint[0]<(Xp[0]+Rmin)) and (i.geom.contactPoint[1]>(Xp[1]-Rmin)) and (i.geom.contactPoint[1]<(Xp[1]+Rmin)):
      intOnInjPoint=i

Of course, you need to define Xp (the injection point) and to compute the minimum radius Rmin before that.

Luc

Hi and good morning Luc,

Thank you so much for providing the code for identifying the interaction.

Please set me straight if I am wrong, what I understood yesterday from your command was that I can open one of the text files (that is produced by the command) and check first three coloums. If the coordinates are close to the injection point (as you pointed out it can never be exactly same) then the fourth coloums is the crack joint aperture of the injection point.

So how the code should be written is to check every row to see if X,Y, and Z are in the vicinity of the injection point coordinates (imposing a range) then if so, add the crack joint aperture (fourth coloum) and finally make an average.

Do I understand the general concept, right?

Thanks for your time and consideration.

Best regards,
Yousef

No, no need to work on the crack file. Just implement the lines I gave you after the first iteration of your simulation (where the bonds are created). Then, you can record the aperture at the injection point (and the corresponding pressure) inside a dedicated function called every n-iteration.

Like this one that I use to record "meta data" in a textfile that I can then process with a dedicated plotting script (in my case, a Python script):

intOnInjPoint=[]
def recordData():
    global e10,e20,e30,intOnInjPoint
    yade.plot.addData(t=O.time,i=O.iter,
 e1=triax.strain[0]-e10,e2=triax.strain[1]-e20,e3=triax.strain[2]-e30,
 s1=triax.stress(triax.wall_right_id)[0],s2=triax.stress(triax.wall_top_id)[1],s3=triax.stress(triax.wall_front_id)[2],
 p=flow.getPorePressure(Xp),
 a=intOnInjPoint.phys.crackJointAperture,
 tc=interactionLaw.nbTensCracks,
        sc=interactionLaw.nbShearCracks,
 unbF=utils.unbalancedForce()
 )
    plot.saveDataTxt(OUTPUT)

Just add the recordData() function in the engines list such as:

PyRunner(iterPeriod=10,initRun=False,command='recordData()',label='data'),

Luc