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[Andrew Jennings <question694974@xxxxxxxxxxxxxxxxxxxxx>]

Question #694974 on Yade changed:
https://answers.launchpad.net/yade/+question/694974

    Status: Needs information => Open

Andrew Jennings gave more information on the question:
Hello Robert,

Thanks for responding so quickly!  I am new to open source DEM.
Hopefully my company can start submitting valuable contributions soon.

Here is an easy to run example of my problem.  First, a working script
with only spheres.  It is a slightly modified version of the gravity
deposition in box tutorial:

from yade import pack,plot,ymport

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=.05,rRelFuzz=.5)

id_matSpheres = O.materials.append(ViscElMat(
	young=1.0e8, 
	frictionAngle=radians(25), 
	density=2160, 
	poisson=0.3,
))
sp.toSimulation(material=id_matSpheres)

O.engines=[
    ForceResetter(),
    InsertionSortCollider([Bo1_Sphere_Aabb(),Bo1_Facet_Aabb()],verletDist=(2.0e-3),label='collider',ompThreads=1),
    InteractionLoop(
        ## handle sphere+sphere and facet+sphere collisions
        [Ig2_Sphere_Sphere_ScGeom(), Ig2_Facet_Sphere_ScGeom()],
        [Ip2_FrictMat_FrictMat_MindlinPhys(en=0.3, gamma=0.4, krot=0.3)],
        [Law2_ScGeom_MindlinPhys_Mindlin(includeMoment=True, includeAdhesion=True)],
    ),
    NewtonIntegrator(damping=0,gravity=[0,0,-9.81]),

    VTKRecorder(fileName='Sph-',recorders=['spheres', 'facets', 'velocity', 'mass'],iterPeriod=10000),
    ]

O.dt=.5*PWaveTimeStep()

O.stopAtIter=30001
O.run()

I am running all my scripts in the cloud and using Paraview to view the
results so all my scripts so I removed all the code around plots.  Now,
here is a script that replaces some of the spheres in the previous
script with polyhedra.  The script exports the new packing in two vtk
files which you can load in paraview and see that the code successfully
generated a mix of spheres and polyhedra.  After the export, the reports
a fatal error when it tries to find an acceptable Law2 for this
interaction.

from yade import pack,plot,ymport,export,polyhedra_utils

#define materials
id_matSpheres = O.materials.append(ViscElMat(
	young=1.0e8, 
	frictionAngle=radians(25), 
	density=2160, 
	poisson=0.3,
))

matPoly = PolyhedraMat(
	young=1.0e8, 
	frictionAngle=radians(25), 
	density=2160, 
	poisson=0.3,
)
id_matPoly = O.materials.append(matPoly)

# Add box to hold our particles
O.bodies.append(geom.facetBox((.5,.5,.5),(.5,.5,.5),wallMask=31))

# Create cloud of spheres
sp=pack.SpherePack()
sp.makeCloud((0,0,0),(1,1,1),rMean=.05,rRelFuzz=.5)

# Replace large spheres by polys
for pos,radius in sp:
    if radius > 0.04:
        t = polyhedra_utils.polyhedra(matPoly,(radius,radius,radius))
        t.state.pos = pos
        O.bodies.append(t)
    else:
        O.bodies.append(utils.sphere(pos,radius))

#export the initial packing
vtkExporter = export.VTKExporter('Mixed.vtk')
vtkExporter.exportSpheres()
vtkExporter.exportPolyhedra()

O.engines=[
ForceResetter(),
	InsertionSortCollider([Bo1_Polyhedra_Aabb(),Bo1_Sphere_Aabb(),Bo1_Facet_Aabb()],verletDist=(2.0e-3),label='collider',ompThreads=1),
	InteractionLoop(
		## handle sphere+sphere and facet+sphere collisions
		[Ig2_Sphere_Sphere_ScGeom(), Ig2_Facet_Sphere_ScGeom(), Ig2_Sphere_Polyhedra_ScGeom(), Ig2_Facet_Polyhedra_PolyhedraGeom(), Ig2_Polyhedra_Polyhedra_PolyhedraGeom()],
		[Ip2_FrictMat_FrictMat_MindlinPhys(en=0.3, gamma=0.4, krot=0.3)],
		[Law2_ScGeom_MindlinPhys_Mindlin(includeMoment=True, includeAdhesion=True), Law2_ScGeom_FrictPhys_CundallStrack()],
	),
    NewtonIntegrator(damping=0,gravity=[0,0,-9.81]),

    VTKRecorder(fileName='Sph-',recorders=['spheres', 'facets', 'velocity', 'mass'],iterPeriod=10000),
    ]

O.dt=.5*PWaveTimeStep()

O.stopAtIter=30001
O.run()

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