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Re: [Opal] number of macroparticles per grid size

From: Adelmann Andreas <andreas.adelmann AT psi.ch>
To: Dragos Constantin <dragos.constantin AT gmail.com>
Cc: "opal AT lists.psi.ch" <opal AT lists.psi.ch>
Subject: Re: [Opal] number of macroparticles per grid size
Date: Wed, 15 May 2024 05:57:05 +0000
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Hi Dragos if you cont between 5 and 10 particles per gridcell you

are on the good side. However it depends what you are interested in

and hence a convergence study is maybe in order. Also we have a

paper on noise published that give some insides: https://www.sciencedirect.com/science/article/pii/S2590055221000111

Cheers A
------
Dr. sc. math. Andreas (Andy) Adelmann
Paul Scherrer Institut OHSA/D17 CH-5232 Villigen PSI
Phone Office: xx41 56 310 42 33 Fax: xx41 56 310 31 91
Zoom ID: 470-582-4086 Password: AdA
Zoom Link: https://ethz.zoom.us/j/4705824086?pwd=dFcvT1pMMGY0bHg0dTNncUNZZTJkZz09

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On 14 May 2024, at 20:38, Dragos Constantin <dragos.constantin AT gmail.com> wrote:

Hi All,

This issue relates to the relationship between the number of macroparticles
and the grid size. (I know that at least the number of macroparticles must be
bigger than the grid size.)

When I setup a simulation model I use a small number of macroparticles with a
relattively small grid size. For example:

REAL N_PARTICLES = 1e4;

REAL MXX = 2^3;
REAL MYY = 2^3;
REAL MTT = 2^7;

So in this case I have ~1.22 macroparticles per grid voxel. I definitely want
to increase the number of particles, the question is do I have to increase the
grid resolution as well? If yes, what is a good choice for the number of
macroparticles/grid voxel?

Thanks,
Dragos

[Opal] number of macroparticles per grid size, Dragos Constantin, 05/14/2024
- Re: [Opal] number of macroparticles per grid size, Adelmann Andreas, 05/15/2024
  - Re: [Opal] number of macroparticles per grid size, Dragos Constantin, 05/16/2024