Re: Can FLUKA (or flair ) be used to caculate region volumes?

Hallo Walker,

in FLUKA you don't have at the moment the analytical calculation of the region
volumes (you can see that at the contrary for some special scoring purpose you
have to provide in input the region volumes, for a correct normalization).

You can, however, calculate your volumes in an indirect, pure Monte Carlo way,
using the tracklength estimator in the volume you want to calculate and the
fact that the total tracklength is proportional to the volume itself.

The steps are the following (thanks to Alberto Fasso'!):
- Assign vacuum to all regions.
- Define a source of any stable particle, uniformly distributed over a sphere
that contains the whole geometry and randomly directed inwards with a cosine
distribution. You can define a such source using BEAMPOS with SDUM=FLOOD.
- Define a tracklength detector USRTRACK for each region, putting in input the
volume = 1.
- Run. The total tracklength, s, scored in each region is proportional to the
volume v of the region. The volume can be carried out considering that the
average chord length, L, of the source sphere is known and is L [= 4/3 R ] = 4V/A,
where R is the radius of the sphere, V is the volume and A the surface.
We have the proportion: v/V = s/L -> v = s (V/L) = s A/4 = s pi R**2

Obviously your result is approximate and depends on your statistics...

I guess that the option in Simple Geo, when you can use it and with the limit
you wrote, remains the best solution.

Hope it helps,
regards,
Anna

Am Thu, 12 Apr 2012 16:39:34 +0800 schrieb wdx456 <wdx456_at_mail.ustc.edu.cn>:
> Thank you, Sion£¡
>
> Such function in simplegeo is really good. However,Since sometimes the FLUKA
>model I have can't be displayed in simplegeo normally, but quite good in
>flair .
> Besides, it seems that simplegeo can't deal with the QUA body.
>
> So,I'm wondering if the region volume caculation work could be finished
>within the FLUKA software itself.
>
>
> Sincerely
>
> Walker
>
>
>
>
>
>From: Sion Koren
> Date: 2012-04-11 18:29
> To: wdx456
> Subject: Re: Can FLUKA (or flair ) be used to caculate region volumes?
> Greetings,
> You can use Dr. Theis software SimpleGeo for that purpose.
>
>
> Good luck,
> Sion
>
> Sent from my iPhone
>
> On Apr 11, 2012, at 2:44 AM, wdx456 <wdx456_at_mail.ustc.edu.cn> wrote:
>
>
>
> Dear FLUKA experts and users,
>
> I come across a situation that FLUKA region volumes need to be caculated
>for further purposes. Can this be realized in FLUKA? If so, how?
>
>
> Thanks!
>
> Walker
Received on Fri Apr 13 2012 - 10:04:06 CEST