LIGGGHTS® - User Forum

Is there a way to have a group of particles being skipped by collision detection and locked in place, ideally while reducing the computation time.

A simulation that I'm running involves filling a tall cylinder with particles and I want to ignore the majority of them and only freeze a certain distance from the top for the next layers.

Simulating the entire stack is not feasible computation time wise on my desktop.

I haven't been able to find functionality like this in the documentation

Thanks,
Alex

Hello,
I am very new in the field of LIGGGHTS. I have already installed LIGGGHTS 3.7.0 version. But I have to work with atom type superquadrics , I have installed the version 3.8.0 too. But while I am simulating the case. It was creating the 3.8.0 version environment. Please tell me how can I change the environment??
Thanks in advance

Hi,
I am trying to simulate a cold hollow sphere mesh surrounded by hot particles. I am using the mass_temperature tag for this, but when I dump the mesh temperature, it doesn't change with time even though the surrounding particles are at a higher temperature than the mesh. Does anyone have any idea if this feature works in LIGGGHTS?

syntax used:

fix cad2 all mesh/surface file Indium226mm.stl type 2 move 0 0 0.007 temperature 300 mass_temperature 0.35

dump meshtemp all mesh/vtk 500 temp*.vtk temp cad2

Thanks!

How to install Liggghts-Public on window 10.

Hi everyone,
I'm simulating a rotating drum and I want to compare the results I obtain using this three methods :
Imposing rotation by using fix move/mesh
imposing rotation by using fix mesh/surface surface_angle_vel
imposing a rotating gravity.

I am trying to generate a relatively large number of bonded conglomerates. However, I need the individual conglomerates to remain unbonded from each other. Is there a way to read in a text file with a specified bonded conglomerate in a way similar to multisphere? Or perhaps define bond creation based on material location at a given time step?

Hello Team,

Greetings. I'm using move/mesh fix to rotate a boundary (something like cylinder (top.stl, bottom.stl, curved.stl) filled with particles). Can we plot / extract velocity (mag) or velocity vector on the curved.stl boundary and view in post-processing? I'm using paraView and can create a glyph for particles but not for this surface?

Any method exists to export data on *.stl boundaries?

Thank you,
Jagan Mohan.

Hello,

I am seeking to set up my simulations to allow for particles to have a certain cohesion factor dependant on their temperature.
I have seen from a previous post in 2011 that this is not a trivial thing to achieve but may be possible with some build around python coding.

I'm hoping someone could guide on a structure of things that need to be achieved in order to allow for temperature-dependent variable to be achieved.

Thanks

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