LIGGGHTS® - User Forum

Hi all,

I am using the particletemplate/multisphere command to create clumps. The command allows the use of self-defined inertia tensor and mass.
I need to adjust also the center of mass. Currently LIGGGHTS uses the monte carlo method to calculate the center of mass.
Does anyone knows how to set the center of mass individually?

Thanks

I m trying to create a group based on the particle size, which will be used to postprocessing for mass fraction evaulation. Can anyone give me a guide.
Thanks in advance.

Dear all

In LIGGGHTS, I want to model a servo wall that compact particles till a specified stress is acting on the mesh. how can I do this? is it possible by mesh/surface/stress/servo??? as I know this fix cotrolls total force acting on the mesh.
any help would be appreciated.
Regards

Tala,

Hello,

I am following the tutorial to install LIGGGHTS post processing :

When I run :
"./install.sh" in the LPP directory I get an error saying :
directory '/home/daniel/bin' not found
create directory or choose different install directory using the -p flag

How should I fix this issue ?

Thanks.

Best regards,
Daniel

Hello everyone,

I am about to set up my workstation and thought I might ask for recommendations regarding the Linux operating system + LIGGGHTS and Paraview installation versions that I should consider.

Which Linux (Ubuntu, Fedora, ..), version of LIGGGHTS and Paraview (v5.0 or v4.0) can you suggest in order to ensure smooth simulations? I am not a Linux expert but I can get some assistance. Also, I would like to be able to run the available plug-ins for Paraview.

I am thankful for any recommendations. Regards,
Joel

Hello all,

Is there any simple way to add a new property as a vector [i][j] that save some an extra data for each [i][j] contacted particles ?

I know how to add new property for each particle separately, but I was wondering if there is any similar way to save property (data) as a reference for both i,j particles.

I want to save some extra contact information (e.g. number of contact, contact duration ) between each pairs, and based on this information I can set my other simulation conditions.

Any help or hints would be very appreciated.

Is there a list of all of the predefined program variable names used in calculations? If so, where can I find it?

Examples of program variables: Atom IDs, Atom Numbers, Young's Modulus, Normal and Tangential Stress, Sphere Radii, Coefficient of Restitution... etc.

I want to create an if statement to alter the simulation based on whether or not the predefined variables above meet certain conditions.

(For an arbitrary variable A that I create, I would refer to it as ${A}, but I do not know the syntax for referring the the program variables.)

Dear all,

I would like to count the overall number of collisions between different types of particles.
For example, I have particles type 1 and particle type 2, I want to know how many times
during my simulation a 1 particle collides with a 2 particle. Is there a way to do this?

Thank you,
Charlie

hallo all,

is there a way to use cad-files (e.g. stl-files) for the command: fix wall/region command ? Or do I have to define the regions by hand?
region cuboid block 0 0.5e3 0 0.5e3 0 0.5e3 side out

Any comments are appreciated, thanks

Joh

Hello,

I am simulating a shear cell using a servo wall as the top surface and a moving mesh as the bottom surface. The rotation period I set is some seconds.