yade-dev team mailing list archive

[Jan Stránský <honzik.stransky@xxxxxxxxx>]

Hello,
what version of Yade and what operating system do you use?
PotentialBlocks are not compiled by default. I can **try** your code and to
help you (without any guarantee to succeed :-)

In general, bodies should have no problems with O.periodic=True, but
interaction evaluation should implement something extra..

cheers
Jan


st 31. 10. 2018 v 17:11 odesílatel Vasileios Angelidakis <
b7063391@xxxxxxxxxxxxxxx> napsal:

> Hi,
>
> I have started working on the "PotentialBlock" code in YADE for the
> generation of polyhedra using the Potential Particles approach. I want to
> use these particles in a periodic cell, but it seems the PotentialBlock
> class is not compatible with periodic boundaries. Would be grateful to get
> any advice on whether this is the case and where I should focus to
> implement it myself? (FYI I am still a rookie in C++ development).
>
>
>
> In the following lines I paste a minimal working script to demonstrate a
> potential block falling through the periodic cell.
> Visualisation of the simulation is available only in a VTK format (not in
> qt).
>
>
> Cheers,
>
>
>
> Vasileios
>
>
>
> Vasileios Angelidakis
>
> Post-Graduate Researcher in Geotechnical Engineering
>
> School of Engineering, Newcastle University
>
>
>
> The script:
>
>
> from yade import pack
> import math
>
> # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
> # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
> # Clear the directory where the VTK results will be written of all files
> (but not subdirectories).
> # The directory is cleared, so files from previous runs do not interfere
> with files from new runs.
> # If the directory does not exist, it is created.
>
> import os, shutil
> folder = './vtk_ele'
> try:
>     os.mkdir(folder[2:])
> except:
>     for the_file in os.listdir(folder):
>         file_path = os.path.join(folder, the_file)
>         try:
>         if os.path.isfile(file_path):
>             os.unlink(file_path)
>     #        elif os.path.isdir(file_path): shutil.rmtree(file_path)
> #uncomment to also delete the subdirectories
>         except Exception as e:
>         print(e)
> # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
> # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
>
>
>
> # Engines
> O.engines=[
>     ForceResetter(),
>     InsertionSortCollider([PotentialBlock2AABB()],verletDist=0.01),
>     InteractionLoop(
>         [Ig2_PB_PB_ScGeom()],
>         [Ip2_FrictMat_FrictMat_KnKsPBPhys(kn_i=1e8, ks_i=1e8, Knormal =
> 1e8, Kshear = 1e8, useFaceProperties=False, calJointLength=False,
> twoDimension=False, unitWidth2D=1.0, viscousDamping=0.05)],
>         [Law2_SCG_KnKsPBPhys_KnKsPBLaw(label='law',neverErase=False)]
>     ),
>
>  NewtonIntegrator(damping=0.0,exactAsphericalRot=False,gravity=[0,-10,0]),
>
>  VTKRecorder(fileName=folder+'/vtkPeriodicCell-VTKRecorder-',recorders=['pericell'],iterPeriod=200)
> ]
>
> # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
> # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
>
>
>
> # Basic dimensions used in the model
> distanceToCentre= 0.5
> meanSize = 1.0
> heightOfBase = 5.0*meanSize
>
> # Material definition
> powderDensity = 2000
>
> O.materials.append(FrictMat(young=150e6,poisson=.4,frictionAngle=radians(0.0),density=powderDensity,label='frictionless'))
>
> # Creation of a spheres packing, following a desired PSD
> sp=pack.SpherePack()
>
> mn,mx=(Vector3(0,0,0),
>        Vector3(4*heightOfBase, 4*heightOfBase, 4*heightOfBase))
>
> sphereRad = sqrt(3.0)*0.5*meanSize
> sp.makeCloud(mn,mx,sphereRad,0,10,periodic=True)
>
> # Replacement of the spheres with cuboids
> count= 0
> rPP=0.05*meanSize
> for s in sp:
>     b=Body()
>     dynamic=True
>     wire=False
>     color=[0,0,255.0]
>     highlight=False
>     b.shape=PotentialBlock(
> k=0.2, r=0.05*meanSize, R=1.02*sphereRad,
> a=[1.0,-1.0,0.0,0.0,0.0,0.0],
> b=[0.0,0.0,1.0,-1.0,0.0,0.0],
> c=[0.0,0.0,0.0,0.0,1.0,-1.0],
> d=[distanceToCentre-rPP,distanceToCentre-rPP,distanceToCentre-rPP,distanceToCentre-rPP,distanceToCentre-rPP,distanceToCentre-rPP],
> isBoundary=False, color=color, wire=wire, highlight=highlight,
> minAabb=Vector3(1.0*sphereRad,1.0*sphereRad,1.0*sphereRad),
> maxAabb=Vector3(1.0*sphereRad,1.0*sphereRad,1.0*sphereRad),
> maxAabbRotated=Vector3(1.0*sphereRad,1.0*sphereRad,1.0*sphereRad),
> minAabbRotated=Vector3(1.0*sphereRad,1.0*sphereRad,1.0*sphereRad),
> AabbMinMax=True,fixedNormal=False)
>
>     length=meanSize
>     V= 1.0
>     geomInert=(2./5.)*powderDensity*V*sphereRad**2
>     utils._commonBodySetup(b,V,Vector3(geomInert,geomInert,geomInert),
> material='frictionless',pos=s[0],  dynamic=True, fixed=False)
>     b.state.pos = s[0] #s[0] stores center
>     b.state.ori =
> Quaternion((random.random(),random.random(),random.random()),random.random())
> #s[2]
>     b.state.mass =V*powderDensity
>     O.bodies.append(b)
>     b.dynamic = True
>     count =count+1
>
> # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
> # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
>
>
> # Set up Periodic Boundaries
> O.periodic = True
> O.cell.setBox(4*heightOfBase, 4*heightOfBase, 4*heightOfBase)
>
> # PotentialBlockVTKRecorder recorder
> sampleQuality=50 # Increase to improve visual quality of the particles in
> Paraview
> O.engines=O.engines+[PotentialBlockVTKRecorder(fileName=folder+'/eleTest_',
> iterPeriod=200, twoDimension=False, sampleX=sampleQuality,
> sampleY=sampleQuality,  sampleZ=sampleQuality, maxDimension=0.2,
> label='PBvtkRecorder')]
>
> # Time step
> O.dt = 0.2*sqrt(0.3*O.bodies[0].state.mass/1.0e9)
> import yade.timing
> O.timingEnabled = True
> yade.timing.reset()
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