Re: Re: Deviations of flux caculation results by FLUKA and MCNP

From: <wdx456_at_mail.ustc.edu.cn>
Date: Wed, 30 Jan 2013 21:22:49 +0800 (CST)

2013 14:23:03 +0100 (CET)
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Hi Paola,

The primary particle is neutron with energy 14MeV and the particle I'm scoring is also neutron.
I didn't find any pattern in the diffferences(Really troublesome:）).

Maybe I should do more careful analysis to find out the true reason.

Then,from your expert view,is it possible that 10% difference of FLUKA and MCNP flux results are the right results?(considering material lib and software differences)

Thanks for your kindness!

Best wishes,
Walker


> -----Original E-mail-----
> From: "Paola Sala" <paola.sala_at_mi.infn.it>
> Sent Time: 2013-1-30 15:39:26
> To: walker <wdx456_at_mail.ustc.edu.cn>
> Cc: fluka-discuss_at_fluka.org
> Subject: Re: Deviations of flux caculation results by FLUKA and MCNP
>
> Dear Walker,
> it is difficult to answer without more information:
> What is your primary particle? Its energy? Which particles are you scoring?
> Do you see some pattern in the differences? For instance, do they depend
> on the position , on the material, or other?
> Regards
> Paola
> > Dear all,
> >
> >
> >
> > Recently, I was trying to calculate flux distribution of a model via FLUKA
> > and MCNP respectively (in order to verify the correctness of my result).
> >
> >
> >
> > The model was made up of over 100 regions and the materials included : C,
> > V
> > , Cr, Mn, Fe, Ta, W, H, He, Li, Pb, Ni, etc.
> >
> > About 50 regions' fluxes were scored.
> >
> >
> >
> > I tried several ways to decrease the relative error. For example, the same
> > volume values were input into FLUKA and MCNP for flux calculation; the
> > primary particles were increased from 1.0e6 to 1.0e7 to 1.0e8; the
> > selfshielded material in FLUKA was also chosen.
> >
> >
> >
> > However, the FLUKA and MCNP results seemed not to match ideally: about 25
> > regions had deviation less than 1%; about 20 ones had deviation between 1%
> > and 2 %; most of the left ones had deviation beside 10% with the max
> > deviation 19%. Both the max statistical discrepancies of FLUKA and MCNP
> > are
> > no bigger than 1%.
> >
> >
> >
> > I' m wondering if my calculation result is correct. What's the reasonable
> > flux deviation of FLUKA and MCNP? How about 10%?
> >
> >
> >
> > Looking forward to any suggestion.
> >
> >
> >
> >
> >
> > Best wishes
> >
> > Walker
> >
> >
> >
> >
>
>
> Paola Sala
> INFN Milano
> tel. Milano +39-0250317374
> tel. CERN +41-227679148
>
Received on Wed Jan 30 2013 - 22:31:14 CET