Re: [sparta-users] EXT :Re: [EXTERNAL] RE: Re: collision models

[Ramakrishnan, S. [U. (D. (Contr) <Sek...@ng...>]

Thank you, Michael!

I am not looking for a perfect solution.  I am wondering whether Steve’s suggestion of 3 models in one simulation may be used an approximate method for modeling flows with mixed gas and solid particles.

In CFD, the particles are treated as  Eulerian Dispersed Phase and it does a reasonable job.

Rama

From: Gallis, Michael A. <ma...@sa...>
Sent: Tuesday, November 4, 2025 3:31 PM
To: Ramakrishnan, Sekaripuram [US] (DS) (Contr) <Sek...@ng...>; Steve Plimpton <sj...@gm...>
Cc: spa...@li...
Subject: EXT :Re: [EXTERNAL] RE: Re: [sparta-users] collision models

I thought I answered this question during the Santa Fe meeting.
The answer is absolutely not. Particles follow a different mathematical model than molecules.

Michael


From: Ramakrishnan, Sekaripuram [US] (DS) (Contr) <Sek...@ng...<mailto:Sek...@ng...>>
Date: Tuesday, November 4, 2025 at 4:20 PM
To: Steve Plimpton <sj...@gm...<mailto:sj...@gm...>>
Cc: spa...@li...<mailto:spa...@li...> <spa...@li...<mailto:spa...@li...>>, Gallis, Michael A. <ma...@sa...<mailto:ma...@sa...>>
Subject: [EXTERNAL] RE: EXT :Re: [sparta-users] collision models
Thank you, Steve.

Rama

From: Steve Plimpton <sj...@gm...<mailto:sj...@gm...>>
Sent: Tuesday, November 4, 2025 3:18 PM
To: Ramakrishnan, Sekaripuram [US] (DS) (Contr) <Sek...@ng...<mailto:Sek...@ng...>>
Cc: spa...@li...<mailto:spa...@li...>; Gallis, Michail A <ma...@sa...<mailto:ma...@sa...>>
Subject: EXT :Re: [sparta-users] collision models

I'm CCing Michael who may be able to comment on whether a mixed HS/VHS collision model makes sense
for a solid/gas particle mixture.  It sounds like you are really asking for a mixture of 3 models in one simulation:
solid/solid, gas/gas/ and solid/gas.

If it does make sense, then we could think about how to implement it.

Steve

On Sun, Oct 5, 2025 at 12:19 PM Ramakrishnan, Sekaripuram [US] (DS) (Contr) <Sek...@ng...<mailto:Sek...@ng...>> wrote:

I am wondering whether such a collision model may be used to simulate a mixture of solid and gas particles with HS model for solid particles and VHS model foe gas particles.

Rama


From: Ramakrishnan, Sekaripuram [US] (DS) (Contr) <Sek...@ng...<mailto:Sek...@ng...>>
Sent: Sunday, October 5, 2025 11:40 AM
To: spa...@li...<mailto:spa...@li...>
Subject: EXT :[sparta-users] collision models

Is there a model for collision between a hard sphere and a variable hard sphere?

Rama
_______________________________________________
sparta-users mailing list
spa...@li...<mailto:spa...@li...>
https://lists.sourceforge.net/lists/listinfo/sparta-users