LIGGGHTS® - User Forum

Dear Liggghts users,
Here is something new specially for Mac users:

http://letstryscience.wordpress.com/2012/02/04/dont-reinvent-the-wheel-c...

Cheers,
Ram

Hi

I would like to generate 2 particles at two points in the space (p1 = [x1 y1 z1] & p2 = [x2 y2 z2]) with initial velocities (v1 = [v1x v1y v1z] & v2 = [v2x v2y v2z). I am not sure if "fix/pour" will be able to do this. Could you guide me through this?

Thank you

Hey

I was just speaking to a visiting lecturer about LIGGGHTS and he said that he had an undergraduate using the code, and noticed something missing in the code to do with the correct calculation of the tangential history. He said it was a few months ago he was looking at it, so I was unsure as to if this may have been picked up and amended.

Dear LIGGGHTS Users,

at the moment I try to run the case "Collapse of a water column" using LIGGGHTS. Actually this is an example of LAMMPS and I am not sure if I can run it with LIGGGHTS.
The atom_style is defined as "meso" and I get the error "Invalid atom style".

Can anybody explain to me why LIGGGHTS doesn't recognise this atom_style "meso"? What is the difference in the sph-model between LAMMPS and LIGGGHTS?

Thank you for your response.
Nate

Hi

I'm a new user , I would like to know the steps on how to install the liggghts properly on Ubuntu. I've downloaded the tar package from the download section into a folder untar the package. The instruction given in the download section for the installation of the stable version does not work for me.

Thanks

Is it possible to use a separate contact law (force vs displacement) on unloading versus what is used during loading? Thanks in advance!

Hi,

We often have the problem to restart a simulation after a specific timestep.
You can make reload-files every N-time, but I think this will cost a lot of time (in fact you are writing down the same information twice in dump- and reload file).

Thats why I coded a tool to transfer a .liggghts file (which was dumped with dump*.liggghts and inherits every data of a single dumpstep) to a reload.pour file.

I attached the code and a 64bit precompiled executable.
The ussage is: d2r INFILE OUTFILE DENSITY (because density is currently not dumped to liggghts-file)

Hi

I would like to impress a force on each atom depending on his mass, velocity an position. While searching through the manual i have found the fix command addforce. I have read "the vector is the total force on the group of atoms". So thats not what I need. But I couldn't find any other fix command that would enable my additional force. In the forum I've read that in a coming version of liggghts variables could be used in fix addforce. Is this in the newest version 1.5 possible? Would that help?
How would you impress an additional force to each atom?

I am trying to simulate mixing of granular particles in a rotary drum mixer. How can give different values to young modulus, coef of restitution, etc for particle particle interaction and particle vessel interaction cause.

Hello everyone!

I am new to this site and forum.
Therefore I want shortly introduce myself:

I am a student from Düsseldorf, Germany
working on my master thesis now.

My job is to simulate a ball mill for grinding processes.
It is similar to the one you have on this site.
A rotating cylinder with steel balls in it should be simulated.

I am new to LAMMPS and LIGGGHTS.
Moreover, I never used Linux, nor have I used or programmed in C++.

What is a best/efficient way to start?

Should I at first get familiar with LAMMPS/LAMMPS manual
or something else?