Yade

spheres pass through cylinder

Asked by hafsa on 2019-02-18

hi every one ,
i have two questions :
1_ i wrote a script of falling spheres into cylinder , the problem is that the spheres pass through it (like it doesn't exist )
why it doesn't work ?
2_ there's command in yade to make spheres semi-transparent ?

the script is :
from yade import pack

density=2500
young=70000
r=.5
constant_damping=0.01

#material of cylinder
Mat1 = O.materials.append(ViscElMat(kn=10.0e4,ks=10.0e4,frictionAngle=0.455,density=2650.0))

#material of spheres
Mat2 = O.materials.append(CohFrictMat(poisson=.22,young=young,density=density))

# create sphere packing
sp=pack.SpherePack()
sp.makeCloud((-7.2,-7.2,18.),(7.2,7.2,82.9),rMean=r,rRelFuzz=0,num=6000,seed=1)
sp.toSimulation(color=(0,1,0),material=Mat2)

# create Cylinder
Cylinder=O.bodies.append(geom.facetCylinder((0,0,30.),10.0,height=60.0,wallMask=6,segmentsNumber=64,material=Mat1))

# interactions
O.engines=[
    ForceResetter(),
    InsertionSortCollider([Bo1_Sphere_Aabb(),Bo1_Facet_Aabb()]),
    InteractionLoop(

        [Ig2_Sphere_Sphere_ScGeom(),Ig2_Facet_Sphere_ScGeom()],
        [Ip2_FrictMat_FrictMat_FrictPhys()],
        [Law2_ScGeom_FrictPhys_CundallStrack()]
    ),
    NewtonIntegrator(gravity=(0,0,-9.81),damping=constant_damping),

]
O.dt=PwaveTimeStep()

thanks in advance

Question information

Language:: English Edit question

Status:: Solved

For:: Yade Edit question

Assignee:: No assignee Edit question

Solved by:: Jan Stránský

Solved:: 2019-02-20

Last query:: 2019-02-20

Last reply:: 2019-02-19

Link existing bug

Revision history for this message

Luc Scholtès (luc) said on 2019-02-19:

Hi,

It seems that you append 2 materials (ViscElMat and CohFrictMat) and then you define interaction physics with Ip2_FrictMat_FrictMat_FrictPhys which is related to another material (FrictMat). Then, you want to use the Law2_ScGeom_FrictPhys_CundallStrack which is related to Ip2_FrictMat_FrictMat_FrictPhys and FrictMat.

My suggestion for your 1st question: define appropriate material (FrictMat: https://yade-dev.gitlab.io/trunk/yade.wrapper.html?highlight=frictmat#yade.wrapper.FrictMat) for both spheres and cylinder and keep the InteractionLoop as it is right now.

Regarding your second question, sorry, I don't understand what you want to achieve since you can visualize your simulation in YADE GUI or in Paraview. In YADE GUI, if you go to the display panel, there is an option "wire" which makes the particles "semi-transparent".

Luc

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hafsa (sebbah.hafsa) said on 2019-02-19:

Hi Luc ,
hanks for answer me , now i change the interaction and material of cylinder but the spheres pass through the cylinder again .

#material of cylinder
Mat1 = O.materials.append(FrictMat(young=20*young,frictionAngle=0.455,density=20*density))

#material of spheres
Mat2 = O.materials.append(FrictMat(poisson=.22,young=young,density=density))

#interactions

[Ig2_Sphere_Sphere_ScGeom(),Ig2_Facet_Sphere_ScGeom()],
[Ip2_FrictMat_FrictMat_MindlinPhys()],
[Law2_ScGeom_MindlinPhys_HertzWithLinearShear()]

Revision history for this message

hafsa (sebbah.hafsa) said on 2019-02-19:

i want to create glass spheres that's why i changed the material of the cylinder

Revision history for this message

Jan Stránský (honzik) said on 2019-02-19:

Just proceed step-by-step, i.e. follow Luc's suggestion to first try with one material. If everything works in the simple configuration (no spheres pass through cylinder), then you can play with materials.

One reason could be that the stiffness is too low and interaction forces are not high enough to prevent spheres passing through the cylinder. Try to increase the stiffness (young parameter)

cheers
Jan

Revision history for this message

hafsa (sebbah.hafsa) said on 2019-02-19:

thanks Luc and Jan my first question was solved ( young=7e6) .
for the second question i want to make some particles semi-transparent to see how they interact inside the cylinder.