LIGGGHTS® - User Forum

Is it possible to use a gaussian distribution of radii for the particletemplate/sphere command? The documentation says it is possible but I am getting the following error:

ERROR: Random style gaussian not available for radius

My pertinent code is:
fix pts1 all particletemplate/sphere 1 atom_type 1 density constant 2500 radius gaussian 0.0003 0.00005
fix pdd1 all particledistribution/discrete 1. 1 pts1 1.0

Thanks,
Will

Hi all,

I have been playing with aggregated particles using a hybrid granular/molecular pair style, and am now introducing heat flow into the simulation. In the current implementation if I exclude the aggregates from neighbor calculations, there is no heat flow between member particles (this, of course, makes sense!). If I remove this exclusion, then heat does indeed flow, but at a rate determined by the thermal properties and the initial overlap when the aggregates are created (i.e. determining the contact area).

I would prefer either to be able to either:

I have an idea about vizing the superquadrics using paraview.
first, creat a superquadric source;
then, read your vtk files including particles postions;
the last, use glyph with custom sources. The following image shows what I have done.

Chen

Hi!
Is it possible to insert group of particles, so that their initial velocity would be against gravity field? I've tried it with

fix pour/dev

command, but it gives me an error message:
ERROR: fix pour: z-velocity must not not be <0.

Thanks,

Timo

This probably relates to this problem, but I've posted a new topic to attach some images...

I have just tried to verify the coordination number for some simple packings (in this case simple cubic). I have computed and dumped the coordination number using computer coord/gran. I was expecting a coordination number of 6 everywhere apart from at the edges...

Hi,
What is the best technique of making dense granular packings in liggghts?
Thanks in advance
Amrita K

I am about to start working both with cohesive materials, and also with heat flow - in both of these cases the contact area between particles is an important parameter. It would be great if this value could be exposed to compute pair/gran/local so that it could also be output via dump local...

I can probably figure out the changes if nobody else finds it useful, but I haven't yet started to dig into the code base ;-)

Thanks! Mark

Hi everyone,

I've been running a simulation that uses a hybrid granular/molecular style, and performing the integration with a "fix rigid molecule". Once these aggregates have settled, I then heat the lower boundary and want to study the heat flow through this material.

Hi LIGGGHTS users,
Can LIGGGHTS do simulations of static granular media like slowly sinking of big particle in the static bed of particles etc?
Thanks in advance
Amrita

Hi everybody,
I am getting too much neighbors for my following file.
I am using the fcc lattice, so it will have have co-ordination no 12.
But the output is giving me co-ordination no as 655.
It creates 655 atoms

###### code starts here ###############
units si
boundary s s s
atom_style granular diameter 0.001 density 9000
atom_modify map array sort 0 0.0
newton off
communicate single vel yes

lattice fcc 0.002
region reg block 0 1.6e-2 0 1.0e-2 0 0.006 units box
create_box 1 reg

create_atoms 1 box units box

pair_style gran/hooke/history 1 0
pair_coeff * *