LIGGGHTS® - User Forum

Hi,

I would like to consider in my simulation, that the material properties (coefficient of friction, Young's modulus ...) of the particles are a function of temperature. There's heat conduction from wall to particles and the particles near the wall are heated up, so each particle has a different time dependent temperature and hence different values of material properties.
My idea is to calculate the material properties every time step for each particle using their current temperature.
Is there any possibility to realize that? If so, how can i do that?

Hi All,

I would like to set the different temperatures to different particles, such as 10C, 20C, 30C, 40C ...100C to particle 1, 2, 3, ...and 10. I have read the commend of "set", it looks the ID could be atom ID range, type range, mol ID range, group ID or region ID, but it can not assign the value to each particles. I am wandering if the the commend "read data" could be used to complement this problems.

I'm trying to import an .stl file into a simulation. I receive an error message that states that 2 or more elements have too many neighbors. I've never seen this before so I'm not too sure what to do. Attached are my input file and my .stl file (renamed as .txt for upload). I make the .stl file in Solidworks if that helps.

Hi everyone,

Now I need to run a modeling of granular flow within an auger mixer. Approximately the total particle number is around 400,000. I have a server with 24 CPUs around. I wonder if this computer can handle this modeling? Anyone can give a hint about this ?

hi everybody,
I am trying to simulate a top and a bottom mesh platen contained by rings. these rings are made by "fix rigid" command using small particles (dia. 0.0002 mm). rings are filled by particles (dia. 0.001 mm). so I use these commands (briefly) :

atom_style granular
boundary m m m
newton off

communicate single vel yes

units si
read_data .../NGIgrains ############reads particles proprties and position

Hi, there
I am trying to implement a tri-axial compression test to calibrate the parameters for contact model.
There could be two geometry for sample, cylindrical and block, right?

How to keep the pressure constant on the meshed wall as the lateral wall area varies under compression?
And another thing, for example, for the cylindrical sample, how to implement a targeted force on the cylindrical wall towards radial direction?
cheers

Hi,
I am new in this field of investigation, so I am trying to do some modifications in LIGGGHTS examples. My goal is to use DEM and CFD for modelling of the Shaft furnace for raw material thermal treatment.

I will be thankful for any advice (or better, for correction of attached code)

I will be also very thankful if anybody send me more of yours own examples or advices how to effectively learn use this tools. (pavol.palicka@tuke.sk)

Best regards
Paul

Here is LIGGGHTS output of my existing problem:

Hello all,

I am trying to create a loop with atom style variable to simulate the effect of a solid reaction on a multispheric body here is my relevant script and the error

Hello everyone,

I am using LIGGGHTS for a fair time. Done with number of simulations. But for one, I had to add external electric forces. For which, I have also added the drag components (0.5*drag_coefficient*rho_air*projected_surface*velocity*velocity).

For my case these components are resulting into substantial amount even to nulify the applied electric force. (Drag coefficient calculated from literature as 1.47 for the velocity range in use).

Hi Everybody,

I am trying to set up CFDEMproject on ubuntu 14.04 LTS, and I am following the same exact steps on githubAccess_public.pdf.

I installed OpenFOAM-2.3.x successfully, and everything went fine up to

cfdemSysTest

and I get some information confirming that the paths are set correctly.

Then I started compiling LIGGGHTS(R) by typing:
cfdemCompLIG