LIGGGHTS® - User Forum

LIGGGHTS® related topics can be discussed here: discussion about models, installation, feature requests and general discussion

wall force

Submitted by hansmannb on Wed, 12/04/2013 - 10:49

Hi,

has someone an idea how to fix this problem?

My challenge is it to move a wall/gran/hertz/history (complex geometry) through a region full of particles to compute the resulting force onto the wall.
I need the force for further calculations in MatLab.

Some ideas?

Regards
hansmannb

Amazon EC2 and StarCluster

Submitted by philmartin on Fri, 11/29/2013 - 02:42

I am experimenting with Amazon EC2 to see if I can get some significant wins in LIGGGHTS running time. I've tried a variety of datasets, and I seem to be encountering some sort of slow down beyond 24 CPUs.

My bigger test dataset I'm running is conveyor a simulation. At the end of the 10 second run, there are around 200k particles. The path the particles travel is quite narrow, but oblique, meaning the simulation is highly sensitive to processor partitioning because there are large empty spaces in the simulation box

gran/hertz/history cohesion sjkr

Submitted by rasoul on Wed, 11/27/2013 - 23:30

Hi,
I faced a weird problem in my simulation and it is that when I use "gran/hertz/history" as a pair_style my simulation work precisely, but when change the pair_style to "gran/hertz/history cohesion sjkr" my simulation does not work and it leads to the following messages repeatedly.

"touching neighbour atoms found, growing contact history"

I would appreciate it if anyone help me to solve this problem.

Sincerely,
Rasoul

Error in compiling user-cuda

Submitted by Ferdinando83 on Wed, 11/27/2013 - 17:26

Dears,
I can compile liggghts with gpu packages and I think it works but I can't compile it with user-cuda.
After the compiling of liblammpscuda.a in lib directory, if I try "make machine" I obtain this error:

pair_gran_hooke_cuda.cpp: In member function ‘void LAMMPS_NS::PairGranHookeCuda::allocate()’:
pair_gran_hooke_cuda.cpp:95:39: error: ‘kn’ was not declared in this scope
pair_gran_hooke_cuda.cpp:96:39: error: ‘kt’ was not declared in this scope
pair_gran_hooke_cuda.cpp:97:39: error: ‘gamman’ was not declared in this scope

problem

Submitted by mozhgan on Wed, 11/27/2013 - 11:34

Hi
how can I fix the problem below?

ERROR: Fix wall/gran/hooke/history (id plate_wall): Fix wall/gran style and pair/gran style have to match, you have to define the wall after the pair style (fix_wall_gran.cpp:251)

thanks so much for your good commands.
Regards mozhgan

problem

Submitted by mozhgan on Fri, 11/22/2013 - 08:05

Hi
H worte a an example but when I run it this error has apeared

ERROR on proc 0: Cannot open dump file (dump.cpp:392)
--------------------------------------------------------------------------
MPI_ABORT was invoked on rank 0 in communicator MPI_COMM_WORLD
with errorcode 1.

What is real Legacy vtk mesh that region mesh/tet supports?

Submitted by keepfit on Fri, 11/22/2013 - 02:07

Hi Chris,

as the command "region ID mest/tet xx.vtk ..." needs a volume legacy VTK file. What I am really confused is that, what is a real legacy vtk mesh that LIGGGHTS supports? And how to make/convert STL mesh to this type of mesh?

Importing STL file into paraview, and save as Legacy VTK, but it is

# vtk DataFile Version 3.0

and using gmsh -2 xxx.stl -o xxx.vtk, it's

Pages

Subscribe to RSS - LIGGGHTS® - User Forum