LIGGGHTS® - User Forum

Hello all,

Heat transfer between two particles is calculated by fix heat/gran with the equation given on

http://www.cfdem.com/media/DEM/docu/fix_heat_gran_conduction.html

Hi All,

I am simulating granular flow on a conveyor belt. Is there a way of tracking individual particle position, forces, velocities per time step or through out the simulation run.

Theo_Score

Hi!
I'm manteining the LIGGGHTS PKGBUILD in AUR. Any doubt, compilation error or suggestion you can make it right here.

You must to install liggghts and liggghts-lpp (Pizza.py) from AUR.

it's you use yaourt, it's enough with:

yaourt -S liggghts-lpp

And you will get the liggghts, pizza and lpp command in /usr/bin

Hello everyone,

I am trying to extract particle velocity and position only one time for each collision, by reading the output only in the first timestep the contact takes place and ignore the output for the rest of contact duration. I want to use these properties by variable command and fix adapt to update particle diameter.

I tried to use "pair/gran/local command", but this command gives me the output every timestep the two particles are in contact and that's not what I needed. I want only one particle property reading for the whole duration of each contact.

Hello,

I'd like to know if in the latest release of LIGGGHTS is implemented the possibility to move a mesh through a periodic boundary condition.
It is mentioned a "very special context". Can you tell me more?

Thanks a lot and have a nice day,
rob1

A part of my syntax is given above.

#parameters for gradually growing particle diameter
variable alphastart equal 0.0001
variable alphatarget equal 0.000125
variable growts equal 50000
variable growevery equal 40
variable relaxts equal 20000

I want start particle insertion after a certain time. I assume this should work with the "start" keyword of insert/stream. However, even if I use the "start" keyword, paticle insertion starts from the beginning. My code looks the follwing:
fix ins nve_group insert/stream seed 5330 start 1e4 distributiontemplate pdd1 &
nparticles 10000 massrate 1e-1 overlapcheck yes all_in no vel constant 0.0 0.0 -1.0 &
insertion_face partIn extrude_length 1e-2
Can anybody give me a hint what's the reason why the "start" option does not work correct?

Hello all

I downloaded the LIGGGHTS code , but when I run a script on the examples, for example

liggghts*in.cohesion

(The * above should be the "less than" simbol. I cannot write it in this forum for some reason).

I get an error saying ‘liggghts’ is not installed. I do sudo apt-get install liggghts, but it keeps saying that ‘liggghts’ is not installed.

I followed the instructions on
http://www.cfdem.com/download-liggghtsr-public

Can anyone comment the right syntax for particle growth and shrinkage problem. I need to increase the radius of 200000 particles from 100 micron 125 micron.

Thank you

Hi all

We have dump image command liggghts which prints atom/particles at certain intervals in jog or png formats. The command may look like following:
dump dump_image all image 1000 png/image*.png type v_diameter zoom 1.0 view 90 90 size 1024 1024 axes yes 0.1 0.01