Search found 2356 matches

by Jaakko Leppänen
Mon Aug 30, 2021 8:38 am
Forum: Users
Topic: Decay heat - burnup step dependency
Replies: 5
Views: 153

Re: Decay heat - burnup step dependency

The momentary results probably also depend on decay data library. JEFF data includes much more very short-lived isotopes compared to ENDF.
by Jaakko Leppänen
Tue Aug 24, 2021 10:30 am
Forum: Events and publications
Topic: Serpent UGM 2021
Replies: 0
Views: 55

Serpent UGM 2021

Because the COVID-19 situation is still imposing serious limitations on international travel, the Serpent User Group Meeting for 2021 will be again arranged as an on-line event. The date for the meeting will be sometime in November / December. We'll post more information in the following months.
by Jaakko Leppänen
Wed Aug 04, 2021 9:45 am
Forum: Validation
Topic: How does Serpent handle missing cross-section libraries during depletion?
Replies: 5
Views: 181

Re: How does Serpent handle missing cross-section libraries during depletion?

Do you have any decay time after the irradiation? Depending on the data, some of the Co-60 may be in the form of meta-stable Co-60m (half-life 10.5 min). Adding a short inactive time interval at the end of the simulation will allow all short-lived products to decay. I'm not sure this will affect the...
by Jaakko Leppänen
Mon Aug 02, 2021 1:09 pm
Forum: Gamma transport
Topic: Dose rate vs. Dose (Geant4-Serpent2)
Replies: 4
Views: 427

Re: Dose rate vs. Dose (Geant4-Serpent2)

Also note that Serpent has an analog photon heating detector (mt -12) that calculates the exact energy deposition from collisions. This should be physically more rigorous compared to using a response function (mt -200) that converts flux to dose. The limitation with the analog detector is that it do...
by Jaakko Leppänen
Tue Jun 29, 2021 4:26 pm
Forum: Input
Topic: Track plotter
Replies: 11
Views: 6663

Re: Track plotter

I'm getting some errors related to the diverging population, but if I set the time cut-offs to 3E-7 the simulation is run to completion and fissions are definitely there.
by Jaakko Leppänen
Thu Jun 10, 2021 8:40 am
Forum: Users
Topic: What is the unit of dr 16
Replies: 2
Views: 206

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: ... on_numbers
by Jaakko Leppänen
Mon Jun 07, 2021 8:55 am
Forum: Development
Topic: Parallelization of pre-processing?
Replies: 1
Views: 140

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: 158

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 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: 291

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: 265

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 ...