LIGGGHTS® - User Forum

Hello,

I am trying to simulate a wet powder and calculate the friction between the substrate and the powder.

I'm trying to calculate the friction force from the spring force.
This is a simple model.
Spring the substrate and the block together and move the block. This creates friction between the block and the powder. This is calculated as the spring force equals the friction.

Now the "fix insert/pack" command doesn't work for creating particles.

I've posted the file and would like your advice.

I am trying in install liggghts on ubuntu and i have done half of the processes but i am stuck at the "make auto" command when i type make auto i am getting this error

Creating list of contact models completed.
make[1]: Entering directory '/home/pakhi/LIGGGHTS-PUBLIC/src/Obj_auto'
Makefile:456: *** 'Could not compile a simple MPI example. Test was done with MPI_INC="" and MPICXX="mpicxx"'. Stop.
make[1]: Leaving directory '/home/pakhi/LIGGGHTS-PUBLIC/src/Obj_auto'
make: *** [Makefile:114: auto] Error 2

Hello All,

Hello Everyone,

I am trying to simulate the motion of granular particles in a microchannel incorporating the DEM collisions and Fluid-drag forces on each particle.

I wanted to ask is there a way to incorporate Brownian Motion aswell?

Hello every one...
i used Hertz contact model in my simulations in following form:
F=(Kn δn- γn Vn ) + (Kt δt- γt Vt )
The first term represents the normal force between two particles while the second term represents the tangential force. Here Vn and Vt are normal and tangential components of the relative velocity. The coefficients K_n, K_t, γ_n, and γ_t are calculated from the material properties.

Hello guys

I wrote this code :

atom_style granular

#atom_modify map array

boundary p p p

newton off

communicate single vel yes

units si

region reg block -0.005 0.005 -0.005 0.005 0.0 0.03 units box

create_box 2 reg

neighbor 0.002 bin

neigh_modify delay 0 contact_distance_factor 1.5

hard_particles yes

Hello!

I am receiving an error when simulating a case with fix viscous command. I will attach the script file. The simulation itself goes normally but after I create vtk files from dump files and open them in Paraview I get the following message:

Hello everybody.

Hello everyone,
I just want to know more about the possibility of Lees-Edwards boundary condition implementation. Actually, this BC is a mixture of periodic boundary condition along with the simple shear flow. So how it can be done in liggghts?
Thank you, in advance for your help.

Hello,

I am working on discharging particles from a flat bottom hopper with an orifice. But even I keep particle frictions low one layer of particles seems to stick to the wall surface of the hopper. Even if I reduce time step and increase Young's modulus the result is the same.

Can someone please help me about that?

Here is my input script:

atom_style granular
boundary f f f
newton off
atom_modify map array
communicate single vel yes
units si #(meters, seconds, kg)
timestep 0.00001
processors * * *