Add one superquadric (cylindrical) particle in simulation

Submitted by skepticalgavin on Tue, 01/10/2023 - 18:25

Hello,

I am running a simulation about granular flow with around 20,000 particles, among which there is one special particle (called "intruder"). Right now, I would like to change the shape of the "intruder" from sphere to cylinder (superquadric), while keeping the shape of other particles as spheres. So how could I do it?

My current "intruder" particle creating code are like:

create_atoms 2 single ${xintr} ${yintr} ${zintr}
group intruder type 2
set group intruder diameter ${dl} density ${rho}

Thanks!

Forums:

mschramm | Tue, 01/10/2023 - 21:29

Hello,
You will have to use the superquadric atom_type for all particles in the system.
For your normal spheres, just set the blockiness values to 2.
For your cylinders, use a call similar to what is found in the examples
create_atoms 1 single 0.0 0.0 0.01
set atom 1 type 2 shape 0.002 0.002 0.004 blockiness ${blockiness1} ${blockiness2} density 2500 vz 0.1 quat 1 0 0 ${angle}