LIGGGHTS® - User Forum

Hello everyone

I have been trying to use multisphere/break command to break the particles when it attains certain kinetic energy during its fall under the influence of gravity. I am unsuccessful in doing that.

source code : fix_multisphere_break.cpp

what does this two lines indicate in the source code

if (triggerName_ && update->ntimestep % modify->fix[triggerIdx_]->peratom_freq)
error->all(FLERR,"Fix used in fix multisphere/break not computed at compatible time");

code :

Dear LIGGGHTS users,

I am wondering whether LIGGGHTS can capture particle contact at periodic boundary. Using periodic boundary condition enables particles to move continuously from one to other sides of particulate domain. If particles position very close to the boundary line, a part of their volume is out of the domain and should contact with other particles positioning at opposite side. Are these contacts considered in the current LIGGGHTS ?

Thank,

Regards,

Nathan,

what atom style should be used to have cubic particles for segregation.Will superquadrics atom style work by specifying blockiness of 300?

Hey guys,

Is it possible to do a fix command in a defined region (within the simulationbox) or is there a way to do a fix-command in a loop or in an if-condition? I tried different ways but it does not work.

Thank you!

Dear community,

I created new contact model and want to verify with analytical/numerical solutions. Does anybody know how to create particles (2 or 3) with predetermined position (known center and radius)?

Best , regards Furkhat

Hi,
I am interested to know method/s to calculate coordination number for superquadrics. The following commands are existing and are meant for spheres:
(compute contact/atom
compute contact/atom/gran
compute coord/atom)

Thanks,
Sounik

Hi,

I am very new to this filed and I am planning to simulate the powder spreading process.
I have a question about what the insertion region mean? Why we need to set that?

Thanks,
Mill

Good morning,

I am using the next and jump commands to iterate over values of some variables in my input file. It was working ok so far, but now sometimes I find that the command just seems to "skip" some values of the variables. In the following set of variables it jumped from a=43 to a=45. Someone knows a reason for it and how to fix it? The skipping seems to be made over all the 4 variables at the same time.

Excerpt from my input file (attached):

Hey everyone,
I'm not sure if this is a problem, but if I create more than one liggghts object (or reinitialise an existing/closed one) I get the following warning:

Hi, RICHTI83!

I always appreciate your sincere comments and help. I've been using 'LIGGGHTS-WITH-BONDS-master' for a while.
Meantime, I was back to examples and tried the beam example. I could run it without any errors.

But the behavior of beam motions is quiet different with your video on Youtube. Only tip particle was broken at a certain time and dropped.
It seems that the force is not transferred properly to the neighboring particles.