Is there any User's Guide for LIGGGHTS?

Submitted by padian on Sat, 05/28/2011 - 11:19

hi, I'm new to this open source DEM code.
I try to find a User's Guide about LIGGGTS to get more information about the code. But it seems that there is only a install guide.

By the way, what's the requirement (or recommended) of computer hardware to use the code?

Thanks for help in advance.

Forums:

ckloss's picture

ckloss | Mon, 05/30/2011 - 09:10

Hi Padian,

>>But it seems that there is only a install guide
No, in doc/manual.html there is a full users guide

>>what's the requirement (or recommended) of computer hardware to use the code?
You can run anywhere from desktop computers to HPC clusters

Cheers,
Christoph

Habibollah Mosadegh | Thu, 01/21/2021 - 19:23

Hi
I am a new to LIGGGHTS and I want to learn this open source code very good and basically. so, I need an exact tutorial that explains me every lines of LIGGGHTS' code. please help me
now I am in trouble with simulation of just a particle in an agglomerate. I have a code that simulates more than one particle(>=2) in an agglomerate. when I change the value of nspheres in fix pts command from >1 to 1, run is stopped.
I need your guides very much
thank you

mschramm | Fri, 01/22/2021 - 00:18

Hello
I am assuming that you are still using the input script from the multisphere example.
fix pts1 all particletemplate/multisphere 15485863 atom_type 1 density constant 2500 nspheres 50 ntry 1000000 spheres file data/stone1.multisphere scale 0.001 type 1

Here you are declaring a multisphere particle of atom type 1 where the assembly of spheres will have a constant density of 2500 kg/m3. It also states that there will be 50 spheres in this multisphere assembly and that the location and size of each sphere can be found in the file "data/stone1.multisphere". "scale 0.001" tells liggghts to scale the values that are read in from the file as the file uses mm. "ntry 1000000" tells liggghts how many samples should be taken to calculate the multisphere's volume.

The fix particletemplate/multisphere command must have more than 1 sphere. If you only want one sphere, look into
fix particletemplate/sphere

sfawn | Mon, 01/24/2022 - 18:46

Hello mschramm,

I am also working on the multisphere example, and trying to implemant it within my previous work.
Basically, I used the silo example and changed all the *.stl files and particle size distribution for my case, and now I want to go from using perfectly spherical particles to particles with satellites surrounding them.

I managed to create these particles that I wanted in two different files similar to "data/stone1.multisphere" from the exemple, let's say I have one particle of radius r1 = 51 um and its six smaller satellite attached to it in stone1.multisphere and an other particle of radius r2 = 27 um and its satellites as well.

From these two "templates", would it be possible to re-use the silo example but, instead of using the perfectly spherical particles, use the templates of satellited particles ? Instead of specifying the coordinates from all of the particles in one big "data/stonex.multisphere" file ?

So far, if I use my two templates in one "data/stone.multisphere", they do not interact one with each other, and if I use two different files, they did not appear at all.

Thanks in advance,

Sebastien

mschramm | Mon, 01/24/2022 - 23:14

Hello,

To reuse the example, you simply need to swap out the template fix and add the needed integration fix and the multisphere fix (see the example input scripts).

What do you mean by "instead of specifying the coordinates from all of the particles in one big data/stonex.multisphere file"?
The template file must contain the needed spheres to define a specific template. Once you have this one template, you can define a insertion fix to randomly populate your simulation domain with this template.

sfawn | Tue, 01/25/2022 - 12:47

Hi,

As a matter of fact, so far I've been using the example without really reading the documentation, especially the insert/stream part.

I thought that, if I wanted for instance 100 particles with their satellites, I had to specify the coordinates of each particles and each satellite in the "data/stonex.multisphere" file, with coordinates relative to my Insertionface coordinates.

I finally managed to use one file, "data/stone.multisphere", and use as you said the insertion fix to have my random distribution.

Thanks a lot for your answer !