Multisphere Help

Submitted by cTop89 on Thu, 03/20/2014 - 14:34

Hello,

I've been trying to use the "fix particletemplate/multispheres" to create clusters of particles with a "fix insert/stream". I am able to get it to insert one template of particles, but if it attempts to insert anymore than that I get an error from "tri_mesh_I.h:90" (I suspect that if more than one template is inserted by the stream at the same timestep, it attempts to create particles in the exact same spot, and it crashed the contact algorithm). Furthermore it seems that the particles that get inserted do not act as a cluster, but instead act as individual particles. I've attached the progress I've made thus far.

I am approaching this the wrong way? Is there any documentation on using a multisphere method to simulate particle shapes? Your site suggests that it's possible (http://www.cfdem.com/non-spherical-particles), but I can't find anything to help me get going with it.

Thanks,
Curt

PS. At the page linked above, the videos aren't linked correctly and can't be viewed.

AttachmentSize
Binary Data cluster_test.tar_.gz46.94 KB

Forums:

Riccardo Maione's picture

Riccardo Maione | Mon, 03/24/2014 - 17:43

Hi,

with LIGGGHTS you can't insert multisphere particles, what you can do is generate a data file, to generate the molecule you need. For example what I do is to use an hybrid granular molecular simulation, then i use moltemplate to generate the molecules and after with a fix rigid the molecules became rigid bodies. if you want a video of multispheres particles I can share u mine.

I hope this could be of some help,

alberthappy | Tue, 03/25/2014 - 22:00

Hi Riccardo,

Can you share the video to me? I'm very interested in how to generate irregular particle and do the modeling in liggghts. Thanks

Fenglei Qi

cTop89 | Tue, 03/25/2014 - 16:05

Thanks for the response.

I suspected that I might be trying to go in the wrong direction. Is there an additional library I need to build into LIGGGHTS to use a hybrid granular molecular simulation?

A video and an example of your input script would be greatly apperciated! Thanks!

----------------------
"Research is what I'm doing when I don't know what I'm doing."
Wernher Von Braun

lperezpozo's picture

lperezpozo | Fri, 12/05/2014 - 22:38

Hi Riccardo!
Can you sent example also to me?
Thanks a lot,

Luis

--
Dr. Luis Pérez Pozo
Department of Mechanical Engineering
UTFSM, Chile
www.lpp.usm.cl

Brian | Wed, 12/20/2017 - 07:04

Hi Curt,

I am interested in creat irregular particles using DEM and then build particle mixtures.
Could you share me some instructions, scripts or videos?

Many thanks

Brian

MiRa | Wed, 03/26/2014 - 10:44

Hi cTop98,

if you want to use the hybrid granular-molecular style, you have to include the MOLECULE package when compiling. There is a forum thread on how to do this.

Best regards,
MiRa

cTop89 | Wed, 03/26/2014 - 22:16

Thanks everyone!

Your help is all greatly appreciated! I'll be playing with this for the next few days, hopefully I can get something working.

----------------------
"Research is what I'm doing when I don't know what I'm doing."
Wernher Von Braun

lin | Thu, 03/27/2014 - 17:42

Hi cTop98 and Braun,

Could you share your experiences on this multi-phase as I want to build up column-shape particles, other than sphere, thanks in advance?

Dragon lin

jjohnfuller | Mon, 12/22/2014 - 14:31

Hi Riccardo

Could you please send me the video and info too ??

Many thanks

Best Regards

John

shahabgol | Tue, 03/03/2015 - 18:36

Could you please send your script about generating multisphere particles?
Thank you so much.

Regards,
SHG

bnaar | Mon, 01/18/2016 - 17:22

Dear Riccardo,

Could you also share the script with me as I just started on working with multi sphere particles.

Best,
Boris

ckloss's picture

ckloss | Mon, 01/25/2016 - 22:40

Hi Boris,

there is now a multisphere example in the examples/LIGGGHTS/Tutorials_public folder of the distro!
You can use any of the fix insert/* commands to generate multispheres

Best wishes
Christoph