Hello everyone, I tell you that I am a new user in LIGGGHTS, and I am working on a program modeling a system consisting of a belt, barriers, box and board. In the latter, the particles fall to the belt that moves at 5 m / s, where they are finally deposited in the box. However, the program does not run, because the following messages appear:
"0 atoms group group" ... .. (does the "group" command work correctly?)
"Error on proc 0: Too many neighbor bins (../neigbor.cpp:1776) .......... (What happens to the neighbors?)
Two other situations that complicate me, occurs in the global variables:
First: The coefficient of restitution does not allow entering the number zero as a value, so I used the value 0.6e-1. Why does this situation happen?
Second: In Young's module, if values of the order of 1e9 are taken, it forces me to take the condition of "hard particles". Why does this situation happen?
This is the program. Please, I need help to solve this problem and make the program run. I do not know what is happening.
Best regards to all.
# Program name: ejemplo_punto_transferencia
## Initialization of parameters
atom_style granular
atom_modify map array
hard_particles yes
boundary m m m
newton off
communicate single vel yes
units si
region reg block -0.60 0.10 -2.85 0.10 -0.20 1.40 units box
create_box 4 reg
neighbor 0.002 bin
neigh_modify delay 0
#neigh_modify delay 0 binsize 0.01
#neigh_modify every 1 check no
## Physical model
pair_style gran model hertz tangential history rolling_friction cdt
pair_coeff * *
timestep 9.37e-6
fix gravedad all gravity 9.81 vector 0.0 0.0 -1.0
## Material properties.
fix m1 all property/global youngsModulus peratomtype 250.e6 2.7e9 182.e9 100.e6
fix m2 all property/global poissonsRatio peratomtype 0.38 0.35 0.3 0.45
fix m3 all property/global coefficientRestitution peratomtypepair & 4 0.7 0.65 0.66 0.4 0.65 0.6e-1 0.6e-1 0.6e-1 0.66 0.6e-1 0.6e-1 0.6e-1 0.4 0.6e-1 0.6e-1 0.6e-1
fix m4 all property/global coefficientFriction peratomtypepair 4 & 0.3 0.32 0.27 0.7 0.32 0 0 0 0.27 0 0 0 0.7 0 0 0
fix m5 all property/global coefficientRollingFriction peratomtypepair 4 0.1 0.2 0.2 0.2 0.2 0 0 0 0.2 0 0 0 0.2 0 0 0
## CAD geometry.
fix correa all mesh/surface file meshes/correa.stl type 4 surface_vel 0 5 0
fix barreras all mesh/surface file meshes/barreras.stl type 2
fix caja all mesh/surface file meshes/caja.stl type 3
fix placa all mesh/surface file meshes/placa.stl type 2
fix sistema all wall/gran model hertz tangential history rolling_friction cdt mesh n_meshes 3 meshes correa barreras caja
## Insert particles.
group grupo region reg # (This does not recognize him does not understand the program when running)
fix pellet all particletemplate/sphere 15485863 atom_type 1 density constant 925 radius constant 0.028
fix pellets all particledistribution/discrete 32452843 1 pellet 1.0
fix insertar_particulas grupo insert/stream seed 32452867 & distributiontemplate pellets & nparticles 100000 massrate 11.39 insert_every 10000 overlapcheck &
yes all_in no vel constant 0.0 0.0 -1.0 insertion_face placa
## Calculations and output variables
fix integrar grupo nve/sphere
compute rke all erotate/sphere
thermo_style custom step atoms ke c_rke vol
thermo 1000
thermo_modify lost ignore norm no
## Run the simulation and record output information.
run 1
dump dmp all custom 1000 post/dump*.ejemplo_punto_transferencia id & type mass x y z ix iy iz vx vy vz fx fy fz omegax omegay omegaz radius
run 747065 upto
The particles fall vertically from the plate with speed -1 m / s to the belt. The belt moves at 5 m / s to transport the particles so that they are deposited in the box.
Do you need me to send you the files in STL format?
The above, does it affect if I use Ubuntu 18.04? I use it currently
alejandro saez | Thu, 05/02/2019 - 04:05
problem with "group" command and neighbors
Hello everyone, can repair some things that complicated me.
However, I still get the following error message that does not allow me to run the program:
"ERROR: Could not find fix group ID"
How do I solve this problem?
Greeting to all
jvvelez | Wed, 09/25/2019 - 17:13
You defined the group before
You defined the group before the particles have finished inserting. Ideally, you should run insertion of particles first and then define group and then run some other process you're doing