Search found 2351 matches

by Jaakko Leppänen
Thu Jun 10, 2021 8:40 am
Forum: Users
Topic: What is the unit of dr 16
Replies: 2
Views: 55

Re: What is the unit of dr 16

Positive reaction MT's refer to microscopic reaction rates. So with dr 16 the flux is multiplied by the microscopic (n,2n) cross section and integrated over space and energy.

For more information, see: https://serpent.vtt.fi/mediawiki/index. ... on_numbers
by Jaakko Leppänen
Mon Jun 07, 2021 8:55 am
Forum: Development
Topic: Parallelization of pre-processing?
Replies: 1
Views: 31

Re: Parallelization of pre-processing?

The problem is that many of the pre-processing routines need to allocate more memory for the processed data. Memory management is not easy to do in an OpenMP parallel loop. Most of the time-consuming subroutines that only process data (such as the Doppler pre-processor) are already parallelized.
by Jaakko Leppänen
Wed Jun 02, 2021 11:52 am
Forum: Users
Topic: Error runing Serpent for the first time after compiling and installation of data libraries
Replies: 1
Views: 55

Re: Error runing Serpent for the first time after compiling and installation of data libraries

The error suggests that there is something wrong with the directory file read using the set acelib card. Did you use the xsdirconvert.pl utility to convert the xsdir file into Serpent format?
by Jaakko Leppänen
Tue May 25, 2021 9:51 am
Forum: Users
Topic: Errors in coupled transport
Replies: 4
Views: 115

Re: Errors in coupled transport

The second error (opti 1 in MPI mode) looks like one of the parallel tasks terminated in an error or crashed. In such case you may not get a proper error message. This probably happened at the end of inactive cycles, when the photon production is switched on. Is this using the latest Serpent update ...
by Jaakko Leppänen
Mon May 24, 2021 9:20 am
Forum: Methods
Topic: Unable to sample fission source - try explicit definition
Replies: 3
Views: 85

Re: Unable to sample fission source - try explicit definition

The error message basically means that Serpent is unable to locate enough source points by random sampling. The most common case where this occurs is when you are running a standard criticality source simulation, but the fissile material covers only a small fraction of the geometry. Serpent samples ...
by Jaakko Leppänen
Fri May 14, 2021 10:38 am
Forum: Input
Topic: Fission matrix
Replies: 13
Views: 3675

Re: Fission matrix

Writing the source from a criticality source simulation using CSW and reading that into an external source simulation with fissions switched off (set nphys 0) is a good way to simulate simulate a critical reactor if the methodology doesn't allow an actual criticality source simulation. This same app...
by Jaakko Leppänen
Tue May 11, 2021 9:47 am
Forum: Development
Topic: Surface for Pressure Vessels
Replies: 2
Views: 65

Re: Surface for Pressure Vessels

Thank you. This seems useful. Can you also comment on the input parameters to the surface card?
by Jaakko Leppänen
Thu May 06, 2021 11:31 am
Forum: Bugs, problems, questions & feeback
Topic: Serpent2 verification/validation
Replies: 3
Views: 103

Re: Serpent2 verification/validation

I agree, but unfortunately we are quite resource-limited. For us it would be great if users were more active in publishing their own validation results (contributions can be added in the Wiki by registering as a user).
by Jaakko Leppänen
Wed May 05, 2021 12:28 pm
Forum: Bugs, problems, questions & feeback
Topic: Serpent2 verification/validation
Replies: 3
Views: 103

Re: Serpent2 verification/validation

Unfortunately we don't have any automated testing procedure available at the moment. There's a lot of validation done by users, but this information is scattered in reports and scientific publications. You may find something relevant for your case from the list of publications: http://montecarlo.vtt...
by Jaakko Leppänen
Wed May 05, 2021 12:20 pm
Forum: Old posts
Topic: Bug in PN scattering cross sections and diffusion parameters
Replies: 5
Views: 30409

Re: Bug in PN scattering cross sections and diffusion parameters

This paper discussing the efficiency of the CFE may also be useful:

https://doi.org/10.1016/j.anucene.2017.03.006