LIGGGHTS® - User Forum

I'm trying to calculate the minimum height amongst different regions in my simulation. For each region, I use "compute region_height all reduce/region region_name max z" to calculate the highest particle. Now I'm trying to find the minimum of height 1, height 2, height 3, and so on. There doesn't seem to be a way I can simply call minimum(height1,height2,height3). Is there any built-in function or work-around that will allow me to find the minimum amongst different global scalars?

Is there anyone using membrane boundary in liggghts? Just like this youtube video https://www.youtube.com/watch?v=mltNl2AphNk.
Which command should I use to bond these particles as a membrane?

I'm noticing that the code crashes pretty early in a simulation if I have multiple cores across a dimension having periodic boundary conditions. Is this a known issue and does anyone have an idea why this tends to happen? It seems that this only occurs with multisphere particles but not with regular spheres.

Greetings,
I tried to run the shear cell example on a 3.6.0 build. Unfortunately, I am getting the following error. I would be extremely grateful if you could help me out with this.

Import and parallelization of mesh cad2 containing 720 triangle(s) successful
ERROR on proc 0: assertion failed (../region_neighbor_list_I.h:156)

I have listed the echo output below.

Cheers
Jagir

Hi,
I am working on multi-sphere particle simulation. when i run the simulation it shows some of particles are suspended/stick with walls and impeller of mixer and do not settle down through out the simulation.
kindly help me
thanks in advance

Hello everyone!

After some struggling with the primary tutorial, I am now trying to build up my own model. Currently, I am confused about two points and any relevant discussion with you will be very helping.

(i) fix nve + relax pressure = fix npt? Is it a correct understanding?

(ii) If I want to calm down of the whole particle assembly (e.g. the kinetic energy as low as possible), what kind of things I can do to achieve this while keep it under acceptable computation time?

KInd regards,
lumb

Dear all,
is it possible to use a compute to get the amount of capillary bonds (e.g. cohesion easo/capillary/viscous) per atom? If not, would it be difficult to write such a compute?

Regards
Valentin

Hello all,

Is it possible to calculate granular temperature of particles? I see that command compute temp/sphere is phased out.

Thanks and regards,
Vinay

Hi!

I trying to use a particular STL volume like a particle generation region using the command "tet/mesh", but I'm having problems. The "tet/mesh" command ask me to use a "ASCII VTK file", so, I'm using PV to convert my STL volume to the VTK file, but this apparently doesn't works.

region bc mesh/tet file meshes/EmisorVTK2.vtk scale 0.001 side in units box

When I compile this, the program tell me:

I wrote a question and now id like to delete this topic.
hmm sortry for this spam but i didnt get out how to do this..

grrets Miro