LIGGGHTS® - User Forum

Hi all,

i want to model particle agglomerates that are hold together by Van der Waals force. For 1 agglomerate i read in the particle positions that form 1 agglomerate. What can i do to insert multiple particles of the same sort and size? Defining every particle position by hand is very tedious. I have 200K agglomerates in total. Multipsheres work nicely but they break ALL at once and i don't want this beaviour if i model the cohesion by Van der Waals force.

THANKS for any hints!

Hi all,

First thanks for the great resource, I have been working on this for hours before I decided to post here.

I have followed the steps of this post: https://www.cfdem.com/forums/installation-error

and think I have VTK installed and have gotten past several issues. Now when I select make auto it runs for a while which is encouraging, but gets stuck on the same errors from this post:

Hi, my name is Joaquin Gonzalez, currently im doing a job in LIGGGHTS.
Its about a test of wear in a mining dump truck, when im in the multisphere case, i recieve the follow error: Energy calculated for multisphere particles is currently not correct.
i will be so thankful if someone can helpme whit this.
I attach the input script and a picture of the screen with the error
Thank you

hello all,
I was going through the internal codes of Liggghts and found that tag and mask variables are set for each particle. can anybody kindly tell me what are those? As far I understood is the tag is the unique id for each particle and the mask is the processor number in which a particular particle's information is stored. kindly correct me if I am wrong.
thanks in advance.

Best,
Tarun

EDIT: issue has been solved, numerical inaccuracy on my part

SORRY

Total # of neighbors = 3481808
Ave neighs/atom = 17.4315
Neighbor list builds = 118828
Dangerous builds = 0
ERROR: Invalid dump style (/build/buildd/liggghts-3.0.3+repack/src/output.cpp:574)
dem@LIGGGHTS:~/Documents/litgg$

any one please help rectifying this error.

can anyone help me with the input script for providing different growth rate for two particles.

Hi,

I am trying to install LIGGGTHS. I saw that VTK must be installed with support for MPI. I did it, and when trying to install LIGGGTHS again I get the following errors.

Is there any way to modify the servo wall fix from:

fix servo all mesh/surface/stress/servo file plate.stl type 1 com 0. 0. 0. ctrlPV force axis 0. 0. 1. target_val 10 vel_max 1. kp 5.

to:

fix servo all mesh/surface/stress/servo file plate.stl type 1 com 0. 0. 0. ctrlPV torque axis 0. 0. 1. target_val 10 vel_max 1. ratio 0.01 mode auto

in between two runs?

Hello all,
I have a question about my code. I would like to simulate a shear test.
During the insertion of particles I got the following error
"ERROR on proc _: assertion failed (../region_neighbor_list_I.h:170)"

But if I increase the size of my domain following the z-axis the problem is solved.
You will find the file in the attachment.

The size of the box region :
region ri block 0.0 0.02 0.0 0.02 0.0 0.001 units box
(The problem is solved wiht region ri block 0.0 0.02 0.0 0.02 0.0 0.014 units box but I have too many particles)