LIGGGHTS® - User Forum

Hi everyone,

dump dumpstress all mesh/gran/VTK 50 post/dump*.vtk id surfaceNorm stress wear cad

Gives me the mesh id and surfacenormal of all the mesh elements.
I wish to know the surfaceNorm of particular mesh id only at the point of contact (wall-particle) and not all of them.
Is there a way to call surfaceNorm in the source code? How can I modify the code?

Please help.
Thank you.

Compared with gedit for LIGGGHTS syntax highlighting, a better environment can be easily modified via geany, just adding new user file without any root permission for all Linux system. Moreover, it can be used as Integrated Development Environment(IDE).
Following images are the results, if you think it is useful ,please contact me by email--hwu13@mails.tsinghua .edu.cn. I don't know why I cannot upload my pictures .

Hi all,

I am trying to create groups of particles with specfic radius. When I create particles I use:

Hi,
i want to calculate local void ratio inside a sample. And i have tried two methods
For the first method, i have try to use "variable...mass"function to calculate the mass of particles in a given region i have set in advance . Then i can derive the local void ratio.but this method always overestimate or underestimate the void ratio because of the existing of particles intersecting with the region boundary.

Hi
maybe the request is not relevant to liggghts but I am using liggghts and have some difficulties in calculating volumetric strain in a specific volume such as a measurement sphere. I was wondering if anybody has developed a matlab code for strain tensor based on the ligggths results.
I will be so gratefull if you help me in this regard.
thank you in advance
ma

I'm new to Magnetorheological Fluid (MRF) simulations and try to get a comprehensive understanding of MRF behavior. I'm working on MRF simulation to obtain shear stress in terms of shear rate and I'm trying to simulate the shear flow of soft magnetic particles by LIGGGHTS software with a periodic box. I want to study the effect of magnetic field on the particle behavior, if possible.

If it's possible, I would appreciate it if you kindly help me and send me a similar LIGGGHTS script file to get familiar with the simulation?

Best regards

Y. Rabbani

Hi all,
I'm going to fill a subspace with particles and then replicating this through the full volume. I inserted the particles by insert/stream command and let them to settle with "fix nve" command. But after useing replicate command for duplicating them, there is a error, can't replicate because of fix atoms properties.

Please let me know if anyone knows why!
Thanks
Elham

Hi all,

I'm using 'gran/hertz/history' for pair_style and 'compute pair/gran/local history' to output tangential force, because I thought 'history' in 'compute pair/gran/local' means the 3 components of tangential force in xyz (i.e. ft1,ft2,ft3). However the results are extremely small.

I have tried 'compute pair/local ... p1 p2 p3 p4' but it is said improper for gran/hertz/history (I think it was changed from original lammps).

Hi,

Hello Liggghts Users,

I wonder wether or not it is possible to create a simulation region that is a slice of a cylinder. For clarification: