LIGGGHTS® - User Forum

I'm trying to simulate a particle size distribution. Using the attached file (with 8 cpus) leads to the wrong amount of overall mass (0.445609 instead of 0.360).

At first the number of 6755 particles (mass 0.359951) is calculated, which is ok. But then only 3904 particle templates (mass 0.293721) can be inserted at step 1. This leads to "WARNING: Particle insertion: Less insertions than requested (fix_insert.cpp:622)". Later on: "inserted 2851 particle templates (mass 0.151888) at step 33334 - a total of 6755 particle templates (mass 0.445609) inserted so far."

Greetings friends,

I was wondering if it's possible to simulate the effect of jamming (blockage) in a screw conveyor due to non-compatible particle size distributions, too high feeding rate, too high friction among particles, etc...

Specifically, do the particles interact with the rotating impeller and can influence its rotation speed ? Or cause the rotational operation to stop ?

Hi LIGGGHTS users,

I am fairly new to LIGGGHTS and modelling a rather simple problem.

What I am basically trying to do, is to fill the rectangular hopper of a screw conveyor, release a stopper (z-plane primitive) and finally start the screw conveyor.

My problem seems to be related to the fix pour/legacy. The same script, as attached to this post, worked when I used fix insert/pack.

Hej guys.

I'm trying to creat a mesh but instead i get this ERROR:

Hi all,
I am writing-up LIGGGHTS tutorial for beginners. Pleas suggest me to improve. Tutorial attached herewith, plz download and see.
Thanks
RC

Hi all
I want to stop a belt conveyor. I tried to unfix a "mesh/surface" and then fix it with a new surface_vel, but an error message shows up.

here is my in file:

Hi all, I set the units system to be si in the beginning.
Later I used fix mesh/surface/stress and export the pressure/shear/stress by dump mesh/vtk.
what's the unit of the output??? the pressure, shear, stress components??
N? Pa? kPa??
I am not sure.
thanks for help

Regards,
Xiuhan

Dear Friends,

I have a few questions about valid input geometries for LIGGGHTS.
What kind of geometries can LIGGGHTS handle? What softwares can create these kind of files?
I have Gambit, Maya, Autocad on my pc. Are there any tutorials for building geometries for LIGGGHTS?
Should I mesh the geometry and export it to LIGGGHTS?

Regards,
Shahab

Hi everyone,

I have one question about cofficient rolling friction. In my case, I used three different material, called type 1 type 2 type 3. the particles (type 1) alway roll a long time to stop on the plane (type 3). the different rolling frictions from (0.1-10) were tried, But still have the same issue.
the following is the line:

fix m5 all property/global coefficientRollingFriction peratomtypepair 3 0.75 0.1 10.86 0.1 0.65 0.59 10.86 0.59 0.65
pair_style gran/hertz/history rolling_friction cdt #Hertzian without cohesion
pair_coeff

Hi, I along with Christian Richter have re-added the fix breakparticle/force feature in LIGGGHTS 2.3.8. The modified repo can be clone from https://github.com/rahulksoni/LIGGGHTS-PUBLIC

The repo contains a breakparticle example and a successful animation of it can be found at https://www.youtube.com/watch?v=QM4JYtjU8v0&feature=player_embedded

Please have a look and suggest for improvements.