LIGGGHTS® - User Forum

Hello,
I have been making DOEs by utilizing the universe variable type

variable var1 universe 1 2 3 4 5
variable var2 universe 0.1 0.2 0.3 0.4 0.5

# DO THINGS WITH var1 and var2

next var1 var2
clear
jump in.liggghts

Is there a way to use the file variable type to read in all of my DOE values from a txt file?

I have tried
variable var1 file vat1_vals.txt
variable var2 file vat2_vals.txt

but when I call

mpirun -n 4 liggghts -in in.liggghts -partition 4x1

Hallo,

unfortunately I do not know how to give different colors to different atom types. Maybe someone can help me. Thank you.

Sincerely yours

Emanuel

Hi all,

I am using LIGGGHTS for a confining process of a cube area. The maximum and minimum of particles are 5mm and 1mm, respectively. Here I use six servo wall to confine the particles, e.g.

fix topwall all mesh/surface/stress/servo file meshes/topwall.stl type 1 com 0. 0. 0.1 ctrlPV force axis 0. 0. -1. target_val ${targetForce} vel_max 20 kp 0.005

I keep updating the value of "targetForce" so as to reach a confining pressure of 50kPa, but I found it very hard even after 5,000,000 step with timestep=2e-7.

Hello, Everybody

I have a problem with dumping stress for my shear stress simulation. Whenever I try dump pxy pressure component I get an error of Illegal thermo_style keyword (when I put pxy into thermo_style) or Illegal variable command (when I use pxy in the variable command)

Could you please help me dump stress components for each timestep?

atom_style granular
atom_modify map array
boundary m m m
newton off

communicate single vel yes

units si

region reg block 0 0.086 0 0.086 0. 0.085 units box
create_box 1 reg

Apologies if this has been covered elsewhere, I did do a search of the forums first.

I've got a test scenario where I'm compressing a particle bed with a servo-controlled mesh. I've run it at targetVal 5 and targetVal 50, but the results are quite different:

https://youtu.be/EBcXjh_FZ9A

I expected targetVal 50 to be similar to the sim on the left, but with forces 10x greater. As you can see, I'm not even getting forces oriented normal to the compressing plate.

Is this normal? Am I doing something silly somewhere?

hello,

Hi,

I am new to LIGGGHTS . I tried to create lmp_auto executable, when I run the command make auto the terminal gives me the error "Could not compile VTK example with ...... " Kindly someone help me solve the problem. I downloaded VTK via homebrew on my macOS and gave the path in Makefile.user correctly

My Makefile.user VTK details,

VTK_INC_USR=-I/usr/local/Cellar/vtk/8.1.1_2/include/vtk-8.1
# Path that contains the VTK libraries
VTK_LIB_USR=-L/usr/local/Cellar/vtk/8.1.1_2/lib

What should I do. Please help me.

Hi,

I am new to Liggghts, I need to know how to create an executable for mac. I read the documentation and still could not create it. kindly help me do it and on how to compile an input script.

Hi,

I need to simulate a conveyor that is moving in a given direction.
The image of the geometries are attached.
The red geometry is the insertion face. The blue is the conveyor.
I need to fill all the six funnels (green). The conveyor (blue) and the insertion face (red) have to move in a given velocity in the x axis.
I used the command mesh/surface to the conveyor and the insertion face and then tried to set move/mesh in the both. LIGGGHTS returned the error:

Hi,
I would like to read data of particles from multiple files, is it possible to do this? So right now for example I have a restart file with a "baseline" case that I would like to combine with a text file.

Right now I tried running:
read_data particle_wall.csv
read_restart restart.1