LIGGGHTS® - User Forum

Hello Team,

Greetings. I'm new to the LIGGGHTS software and trying to insert particles using the following script. I get an error which says
"ERROR: Fix insert/pack (id vlfrINJ3): overflow in particle number calculation: inserting too many particles in one step (../fix_insert_pack.cpp:345)"

I want to insert same particle(s) using two particle types as I want to track later type during simulation. There are being injected by vlfrINJ3 fix. Upon seeing this error, I reduced volFrac to a very low number but still I get same error? What could be the mistake in this?

Hi,

I would like to remove the mesh after applying the desired stress by using fix/mesh/surface/stress/servo.

I have come to know about "surface mesh feature remove" as indicated in the following links:

https://www.cfdem.com/forums/surface-mesh-feature-remove

https://www.cfdem.com/forums/removed-meshsurface-34-version

Hi Mschramm,

In addition to our last conversation please see the attached a new full input script with mesh, the error as shown below:

Hi,

This is not a problem per se but maybe a suggestion for improvement.

I have a system periodic in x and y. When I use the following custom command, the vtp files are not correctly read into paraview, they just read as empty and the problem is an empty array that appears in the vtp files:

dump dmpgrow all custom/vtk 10000 post/growing_packing_*.vtp id type x y z xu yu zu ix iy iz vx vy vz fx fy fz omegax omegay omegaz radius


Hello,
I am trying to fill a box with 3 different sized spheres but only the largest two spheres are being inserted.

I have called the template fix 3 times with 3 different sized spheres then I call the distribution fix and have
30% for the smallest sphere, 35% for the med, and 35% for the largest but I am not seeing the smallest sphere.

I attached a simple file that replicates my error. LIGGGHTS version is the public 3.8 release.
Any help/suggestions would be greatly appreciated.
Thank you.

Dear all
I cant find any source code that directly related to those.
and is it possible to dump voidfraction and uf (fluid velocity) in the LIGGGHTS side?

regards

Tom

Hello Team,

Hello,
I want to fill up a cylinder with particles. I try the following code, but get an error "Expected integer parameter in input script or data file". Since LIGGGHTS does not tell which line has the error I tried changing every float value to integer to see what's wrong, but I could not find the problem.

I would be grateful if someone helps me out! The code's attached herewith.

Hello and good morning/afternoon,
I have a few questions related to the timings LIGGGHTS outputs to the screen/log file at the end of a run as well as some scalability issues im facing.
So i'm running granular simulations of around 500 000 particles discharging in an hopper. I ran the simulation 10 and 100 timesteps with different number of cores to gauge scalability. I used the most recent LIGGGHTS version in Ubuntu 18.04LTS.

Dear CFDEM users,
I need to define two atm types, however, I faced an error.
ERROR: Fix property/global (id m1): Fix property/global: Length not correct for variable youngsModulus, length should be equal to 1 (= number of atom types) (/build/liggghts-QCz4in/liggghts-3.3.1+repack1/src/fix_property_global.cpp:244)
Here is the material properties definition:
Material properties required for granular pair styles
fix m1 all property/global youngsModulus peratomtype 5.e6 5.e6
fix m2 all property/global poissonsRatio peratomtype 0.45 0.45