I am trying to use the insert/rate/region command to create a cylinder filled with particles. I have not been able to figure out what role the nparticles keyword plays in determining the number of particles added. I thought that the total number would be limited to "nparticles", but when I run the simulation new particles keep being added after reaching "nparticles". How do I create a region with a fixed number of particles? The code is below. Thanks in advance for your help.
fix ins all insert/rate/region seed 3645 distributiontemplate pdd nparticles 100000 particlerate 1000000 insert_every 1000 overlapcheck no region factory
| Attachment | Size |
|---|---|
 in.scratch_1.txt | 2.32 KB |
| log.liggghts_3.txt | 213.24 KB |
cstoltz | Mon, 07/15/2013 - 04:04
Can you post the log file?
Can you post the log file? nparticles should be the maximum number of particles generated so I'm curious as to what the log file looks like.
ckloss | Mon, 07/15/2013 - 15:22
Hi,
Hi,
which version are you using? can you post the full in-file as well?
Christoph
ktduclos | Mon, 07/15/2013 - 23:53
in file
# A simple simulation of a cylinder filled with sand
# Based on a combination of the example movingMeshGran
# and a tutorial by Chris Stoltz
### Initialization
units si
atom_style granular
boundary f f f
newton off
communicate single vel yes
#processors 2 2 1
# Domain
region domain block -0.05 0.05 -0.05 0.05 -0.05 0.05 units box
create_box 1 domain
# Neighbor listing
neighbor 0.0002 bin
neigh_modify delay 0
### Setup
# Material properties
fix m1 all property/global youngsModulus peratomtype 5.e6
fix m2 all property/global poissonsRatio peratomtype 0.45
fix m3 all property/global coefficientRestitution peratomtypepair 1 0.05
fix m4 all property/global coefficientFriction peratomtypepair 1 0.05
fix m5 all property/global characteristicVelocity scalar 2.
# Physics, integrator, and gravity
pair_style gran/hooke/history 1 0
pair_coeff * *
fix int all nve/sphere
fix grav all gravity 9.81 vector 0.0 0.0 -1.0
timestep 0.0000002
# Make some walls
fix bottomWall all wall/gran/hooke/history 1 0 zplane -0.05 0.05 1
fix cylinderWall all wall/gran/hooke/history 1 0 zcylinder 0.05 1
# Particle insertion
# Pour
# group nve_group region domain
# fix ins nve_group pour 1000 1 427389 vol 0.5 1000 diam uniform 0.0002 0.0002 dens uniform 2500 2500 rate 0.1 region factory
# Insert/rate/region
region factory cylinder z 0. 0. 0.05 -0.05 0. units box
fix pts all particletemplate/sphere 1 atom_type 1 density constant 1000 radius constant 0.0002
fix pdd all particledistribution/discrete 324434 1 pts 1.0
fix ins all insert/rate/region seed 3645 distributiontemplate pdd nparticles 10000 particlerate 100000 insert_every 1000 overlapcheck no region factory
# Thermodynamopiic settings
compute 1 all erotate/sphere
thermo_style custom step atoms ke c_1 vol
thermo 1000
thermo_modify lost ignore norm no
compute_modify thermo_temp dynamic yes
# Insert first particles and run time step check
fix ctg all check/timestep/gran 1 0.01 0.01
run 1
unfix ctg
# Make a dump of particles and the stl file
dump dmp all custom 200 post/dump.scratch id type type x y z ix iy iz vx vy vz fx fy fz omegax omegay omegaz radius
# dump dumpstl all stl 200 post/dump*.stl
### Run simulation
run 500000 upto
unfix ins
run 10000
ktduclos | Tue, 07/16/2013 - 00:48
This version of the in file works.
Sorry to post the in file twice. I just found the place to upload files. The version here with the command "run 500000 upto" seems to work. However, when I increase the time to 1000000 (as it is in the uploaded version), the simulation adds 20000 instead of 10000 particles.
cstoltz | Tue, 07/16/2013 - 11:07
According to your logfile,
According to your logfile, you're using LIGGGHTS 1.5. Try upgrading to the most recent version as there has been substantial improvement in the code since then.
Regards,
Chris
ktduclos | Thu, 07/18/2013 - 18:12
Fixed
You were right. This seems to have been fixed in 2.3.6.
Thanks for your help,
Keivn
ckloss | Thu, 07/18/2013 - 18:12
>>According to your logfile,
>>According to your logfile, you're using LIGGGHTS 1.5. Try upgrading to the most
>>recent version as there has been substantial improvement in the code since then.
Agreed.
Christoph