Inserting paricles

I need to insert particles into the container I made in stl format (as servo wall). Can anyone send me the command for running it in liggghts. I tried the commands on tutorial but it doesnt work. A lot of error and warning messages are showing. Some may be due to the version change. Could anyone pls send me a working command in txt format

Attachment	Size
fuelcell_2.stl_.tar_.gz	2.71 MB

Forums:

CFD and DEM - General Discussion

richti83 | Tue, 02/09/2016 - 12:52

It would be easier you would

It would be easier you would share your input skript and geometry here because I don't understand what command exactly gives you problems.

ullassssss | Tue, 02/09/2016 - 13:15

Actually I tried the shear

Actually I tried the shear cell example in the tutorial. log file is as follows
LIGGGHTS (Version LIGGGHTS-PUBLIC 3.0.3, compiled 2014-08-28-20:04:12 by kloss based on LAMMPS 23 Nov 2013)
### Initialization

# Preliminaries

units si
atom_style sphere
boundary f f f
newton off
communicate single vel yes

# Declare domain
region reg block -0.325 0.325 -0.325 0.325 -0.001 0.081 units box
create_box 2 reg
Created orthogonal box = (-0.325 -0.325 -0.001) to (0.325 0.325 0.081)
2 by 2 by 1 MPI processor grid
neigh_modify delay 0

### Setup

# Material and interaction properties
fix m1 all property/global youngsModulus peratomtype 1.0e7 1.0e7
fix m2 all property/global poissonsRatio peratomtype 0.25 0.25
fix m3 all property/global coefficientRestitution peratomtypepair 2 0.5 0.5 0.5 0.5
fix m4 all property/global coefficientFriction peratomtypepair 2 0.5 0.5 0.5 0.5

# Physics

pair_style gran model hooke tangential history
pair_coeff * *

# Particle setup – insertions to be handled below
fix pts1 all particletemplate/sphere 1 atom_type 1 density constant 1000 radius constant 0.003
fix pdd1 all particledistribution/discrete 63243 1 pts1 1.0

# Geometry
fix cad1 all mesh/surface/stress file LIGGGHTS_Examples/shearcell/shear_cell.stl type 1 scale 0.001 stress on
fix cad2 all mesh/surface/stress file LIGGGHTS_Examples/shearcell/bottom_plate.stl type 1 scale 0.001 stress on
fix ins_mesh all mesh/surface/planar file LIGGGHTS_Examples/shearcell/factory.stl type 1 scale 0.001
fix geometry all wall/gran model hertz tangential history mesh n_meshes 2 meshes cad1 cad2

### Detailed settings

# Integration

fix integrator all nve/sphere

# Gravity

fix grav all gravity 9.81 vector 0.0 0.0 -1.0

# Timestep

timestep 0.00002

# Thermodynamic output

thermo_style custom step atoms ke cpu
thermo 10000
thermo_modify lost ignore norm no

### Execution and further settings

# Particle insertion – large particles

fix ins1 all insert/stream seed 1001 distributiontemplate pdd1 nparticles 5000 particlerate 1000 overlapcheck yes insertion_face ins_mesh extrude_length 0.6
run 50000
ERROR: Could not locate a fix/property storing value(s) for characteristicVelocity as requested by model hooke. (/build/buildd/liggghts-3.0.3+repack/src/modify_liggghts.cpp:313)

ullassssss | Tue, 02/09/2016 - 13:22

please take a look at the

please take a look at the container i made. i need to insert the particle into it and settle it. also have to find the particle-particle stress as well as container wall stresses. pls help me to create the syntax

richti83 | Tue, 02/09/2016 - 17:48

Error

I don't know the tutorial you are talking about but the error messages
ERROR: Could not locate a fix/property storing value(s) for characteristicVelocity as requested by model hooke. (/build/buildd/liggghts-3.0.3+repack/src/modify_liggghts.cpp:313)
means you lost a
fix m5 all property/global characteristicVelocity scalar 2.
in the # Material and interaction properties section.
Note: this is only needed for contact modell hooke, mybe you changed pair style from hertz to hooke ?

About p-p and p-w stress have a look at compute pair/gran/local and wall/gran/local, search the forum I posted somewhere an example how to dump it and how to display it in ParaView.
I did not run your script until now bc. I'm in a hurry, sorry.

ullassssss | Thu, 02/11/2016 - 07:09

Sir I couldn't find the

Sir I couldn't find the example u mentioned above. Please post the link if u can. Actually im working for the simulation of metal hydride particles in a container. The particle size is of the order 18 micron and the cylindrical container has a radius of 12mm. Can u suggest a proper insert/rate/region command, velocity etc.. for this particular situation. Im a beginner in liggghts.