LIGGGHTS® - User Forum

Hello
I am using "Flexible fiber" version and have a general question. In the 'lib' folder I found several ANCF beam libraries. I am wondering whether they can be used in Discrete method, or FE by importing a CAD file.

Thanks
Shubham

Hi
I am trying to break granular tupe bonds, by using the command:
fix bondbr3 all bond/break 1 2 ${adh_crit_dist}
2- bondtype
${adh_crit_dist} - critical distang to break the bond

I have also tried fix bondbr3 all bond/break/gran 1 2 ${adh_crit_dist}
But I am getting the following error:
Invalid fix style: "bond/break"

Can we model bond breakage for granular bonds?

Thanks

Hi
I wan to simulate a system very close to as shown in attached figure.
A discrete plastic web is bonded to a non-deformable but movable substrate. As the web his the wall, web should de-laminate from the substrate depending on the bond strengths.
How can the above problem modeled in LIGGGHTS?
How can we create breakable bonds between particle and non-deformable substrate?

Requesting for help, I am struggling a lot, as I am new to the environment

Thanks

Hello
I am trying to simulate a fiber fall. Once they hit the ground, i want to cross-link the fibers based on a critical distance. For cross link bond formation, i am using bond/create command. How wever I an getting the folloing error:
ERROR: Invalid fix style: "bond/create" (../modify.cpp:852)

Thanks
SHUBHAM

Following is my input script:
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
atom_style sphere
atom_modify map array sort 0 0
boundary m m m
newton off

communicate single vel yes

I am trying to set up a basic homogeneous cooling simulation. I am loading in 1000 particles in a periodic domain. Initially, I run the simulation with coefficient of restitution equal to 1. To me, this should result in a nearly constant kinetic energy for the system. However, the velocities shoot way up (depending on time step size). Eventually the kinetic energy decreases as expected after a lower coefficient of restitution is set. My question is what is causing the kinetic energy to increase? This should not even be physically possible if there is no gravitational force.

Hi, I am trying to run a triaxial test. I have defined properties as:
# interaction property [NOTE: Young's modulus value is same for both particle and wall]
variable y1 equal 65e9 # Young's Modulus particle-particle [Pa]
variable y2 equal 6.5e9 # Young's Modulus particle-wall [Pa]
variable us_pp equal 0.15 # Coefficient of static friction particle-particle
variable us_pw equal 0.05 # Coefficient of static friction particle-wall
variable ur_pp equal 0.01 # Coefficient of rolling friction particle-particle

Hello

I want to fill a defined region with fibers. I am creating fibers calling a text file which consists particles' coordinates and radius. I am calling it using the commands below:
fix pts1 all particletemplate/multisphere 15485863 atom_type 1 density constant 2500 nspheres 10 ntry 1000000 spheres file mult.txt scale 0.01 type 1
fix pdd1 all particledistribution/discrete 15485867 1 pts1 1.0
Here 'mult.txt' has the coordinate information

Dear Forum,

I was wondering if it is possible to make DEM simulations while some particles are steadily expanding at a given rate. Should it be enough to mark the particle radius as a variable and make it evolve with time?

Regards,

Oier.

Hello Everyone,

I have a query regarding the simulation I am doing right now regarding slurry flow (carbon particles moving in a flowing water) in a microchannel to simulate charge transfer between particle-collector and particle-particle.