This was supposed to be an easy simulation but I am stuck here.
1) I am inserting particles in cylinder for few seconds
2) After insertion I want to settle it and make a packing in cylinder. My main aim is to fill cylinder more than 80% and make packing tighter.
When I run my script, simulation goes well. But while visualizing it, I see that particles are not piling up in cylinder instead, it penitrate my cylinder buttom and goes out.
I did used f f f boundary condition but I am still not able to fix it.
For sure, my mesh file does have solid buttom.
I am expecting quick suggestion of help ....
I have uploaded my script and mesh file here..
THank youy
```
###################################Header for General commands#######################################################
atom_style granular #Simulation of particles
boundary f f f #fixed boundaries -> particles will be deleted if leaving the simulation box
units si
communicate single vel yes #default
newton off #default
###################################System variables##################################################################
#Definition of boundaries
variable xmin equal -5
variable xmax equal 5
variable ymin equal -5
variable ymax equal 5
variable zmin equal 0
variable zmax equal 35
#Definition of the timestep
variable dt equal 1e-6 #timestep = 0.0001 second; Each iteration step represents 0.0001 seconds.
###################################Specific variables for current simulation#########################################
variable natoms equal 2
####variable for material properties####
####Young Modulus####
variable youngmodulus1 equal 1e8 #N/mm²
variable youngmodulus2 equal 1e8 #N/mm²
####Poission ratio####
variable poission1 equal 0.3
variable poission2 equal 0.3
####variable for contact properties####
####coefficient of restitution####
variable CoR11 equal 0.6
variable CoR12 equal 0.6
variable CoR21 equal 0.6
variable CoR22 equal 0.6
####sliding friction coefficient####
variable sf11 equal 0.3
variable sf12 equal 0.3
variable sf21 equal 0.3
variable sf22 equal 0.3
####rolling friction coefficient####
variable rf11 equal 0.6
variable rf12 equal 0.6
variable rf21 equal 0.6
variable rf22 equal 0.6
####variable for particle####3) inserted so far.
#Number of particle radius
variable nradii equal 1
variable radius1 equal 0.1 #m
variable frac1 equal 1.0 #100%
variable density equal 2000 #kg/m³
####filling parameters####
variable filltime equal 8 #seconds
variable fillmass equal 8000 #kg
variable fillmassrate equal ${fillmass}/${filltime} #kg/s
variable fillsteps equal ${filltime}/${dt} #Transform time to iteration steps
####settle time####
variable settletime equal 10 #second
variable settlesteps equal ${settletime}/${dt} #Transform time to iteration steps
###################################Definition of simulationbox#######################################################
region reg block ${xmin} ${xmax} ${ymin} ${ymax} ${zmin} ${zmax} units box
create_box 2 reg
neighbor 0.004 bin #default3) inserted so far.
neigh_modify delay 0 #default
#################################Definition of the contact models####################################################
pair_style gran model hertz tangential history rolling_friction epsd2 #contact model
pair_coeff * * #default
timestep ${dt}
fix integrator all nve/sphere #default
fix gravi all gravity 9.81 vector 0.0 0.0 -1.0 #gravity of 9.81 m/s² in negative z direction
###################################Definition of Material properties#################################################
fix m1 all property/global youngsModulus peratomtype ${youngmodulus1} ${youngmodulus2}
fix m2 all property/global poissonsRatio peratomtype ${poission1} ${poission2}
fix m3 all property/global coefficientRestitution peratomtypepair ${natoms} 0.6 0.6 0.6 0.6
fix m4 all property/global coefficientFriction peratomtypepair ${natoms} ${sf11} ${sf12} ${sf21} ${sf22}
fix m5 all property/global coefficientRollingFriction peratomtypepair ${natoms} ${rf11} ${rf12} ${rf21} ${rf22}
###################################Generation and Loading of the Geometry .stl#######################################
fix cylinder all mesh/surface file cylinder.stl type 2 scale 0.001
fix walls all wall/gran model hertz tangential history rolling_friction epsd2 mesh n_meshes 1 meshes cylinder
###################################Generation and Insertion of the particles#########################################
fix pts1 all particletemplate/sphere 10487 atom_type 1 density constant ${density} radius constant ${radius1}
fix pdd1 all particledistribution/discrete 32452867 ${nradii} pts1 ${frac1}
fix ins_mesh all mesh/surface/planar file insertionface.stl type 1 scale 0.91
fix ins all insert/stream seed 86028157 distributiontemplate pdd1 &
mass ${fillmass} massrate ${fillmassrate} overlapcheck yes all_in yes vel constant 0 0 -0.1 &
insertion_face ins_mesh extrude_length 1
###################################Dumping of the data for post-processing to visualize############################
shell mkdir post
#Definition of the dumptime
variable dumptime equal 0.05 # Every 0.05 s 1 image
variable dumpstep equal ${dumptime}/${dt} #Transform to iteration steps
dump dmpparticle all custom ${dumpstep} post/particles_*.liggghts id type x y z vx vy vz fx fy fz radius mass
dump dmpcylinder all mesh/stl ${dumpstep} post/cylinder*.stl cylinder
dump dmp all custom/vtk ${dumpstep} post/particles_*.vtk id type type x y z ix iy iz vx vy vz fx fy fz mass radius
dump dmp0 all custom ${dumpstep} preprocessing_data/dump*.data id type x y z mass radius
fix ts_check all check/timestep/gran ${dumpstep} 0.1 0.1
thermo_style custom step cpu atoms ke f_ts_check[1] f_ts_check[2] #f_ressort # ke
thermo ${dumpstep}
####################################RUN the simulation filling###########################################################
#run ${fillsteps}
run 15000000
unfix ins
##################################RUN the simulation #settling#############################################################
run ${settlesteps}
unfix ins
```