Search found 13 matches

by MojoJojo
Sun Apr 19, 2020 3:00 am
Forum: Users
Topic: Pulsated Neutron Test - Question about Scoring Efficiency
Replies: 0
Views: 359

Pulsated Neutron Test - Question about Scoring Efficiency

NOTE: Scroll down to " Now my question! " if you are not interested in all this blabbing. Hello everyone, I'm performing a pulsated neutron test using a Deuterium-Deuterium fusion-based neutron generator (DD). I modified the usersrc.c subroutine in order to define the energy and relative yield angul...
by MojoJojo
Tue Mar 03, 2020 7:11 am
Forum: Bugs, problems, questions & feeback
Topic: Time dependence in external source
Replies: 13
Views: 3254

Re: Time dependence in external source

Nevermind actually. I figured it out :)
by MojoJojo
Fri Feb 28, 2020 8:37 pm
Forum: Bugs, problems, questions & feeback
Topic: Time dependence in external source
Replies: 13
Views: 3254

Re: Time dependence in external source

It works but not for multiple energy groups. I had an option in the Matlab code to generate 'm' number of point sources with different energies at the same location. And when I do that, I'm back to the same problem :( Sorry, I'm not sure I understand, which problem? Could you tell more about what y...
by MojoJojo
Mon Feb 24, 2020 9:15 pm
Forum: Bugs, problems, questions & feeback
Topic: Time dependence in external source
Replies: 13
Views: 3254

Re: Time dependence in external source

Hi, could you try re-running the simulation with just a single time interval of 100 seconds in the srctime definition? Serpent is probably sampling points from the source file only for the first time interval (and rejecting all points that are after the end of that first interval) and the source fo...
by MojoJojo
Sat Feb 22, 2020 1:33 am
Forum: Bugs, problems, questions & feeback
Topic: Time dependence in external source
Replies: 13
Views: 3254

Re: Time dependence in external source

Each entry in the source file represents an individual source neutron. So if you want a constant source over the time interval, you need to sample the initial time (the last value of each row) uniformly between the beginning and end. Hey Jaakko, I was trying to simulate a beamed external neutron so...
by MojoJojo
Fri Sep 27, 2019 11:45 pm
Forum: Bugs, problems, questions & feeback
Topic: Neutron source
Replies: 6
Views: 2375

Re: Neutron source

Unfortunately, no. Did you already check the usersrc.c subroutine? If you have a Matlab script that samples the source particles, you could basically implement the same routine directly in Serpent without the file I/O. I just did. I already made a Matlab script that generates source vectors and ass...
by MojoJojo
Thu Sep 26, 2019 11:20 pm
Forum: Bugs, problems, questions & feeback
Topic: Neutron source
Replies: 6
Views: 2375

Re: Neutron source

The energy can be set using "se <E>". Unfortunately at the moment there is no way to set the emission time, but there is a way around the problem using a pre-generated source file. If you define the entire source using: src <name> sf <file> 1 Serpent will read the source points from file "<file>". ...
by MojoJojo
Sat Jun 15, 2019 1:09 am
Forum: Users
Topic: Response function output of a helium-3 detector makes no sense
Replies: 4
Views: 675

Re: Response function output of a helium-3 detector makes no sense

The output of detector 2, multiplied by the volume, gives you the total absorption rate in the helium. Detector 5 is a microscopic rate, so you would need to multiply the result with material density and volume to get the corresponding (n,p) rate. Do you have an estimate on what reaction rate shoul...
by MojoJojo
Fri Jun 14, 2019 7:59 pm
Forum: Users
Topic: Response function output of a helium-3 detector makes no sense
Replies: 4
Views: 675

Re: Response function output of a helium-3 detector makes no sense

Both detectors 2 and 5 represent reaction rates. The difference is that detector 2 gives the macroscopic reaction rate (total absorption xs multiplied by flux and integrated over variables) and detector 5 the microscopic reaction rate (microscopic (n,p) xs multiplied by flux and integrated over var...
by MojoJojo
Fri Jun 14, 2019 12:19 am
Forum: Users
Topic: Response function output of a helium-3 detector makes no sense
Replies: 4
Views: 675

Response function output of a helium-3 detector makes no sense

Hello, I'm designing a subcritical molten salt reactor experiment, driven by a constant external neutron source. The test core looks as follow: https://i.ibb.co/jTCD9Tz/Description.png So the goal is to determine the total temperature reactivity coefficient using the change in neutron flux only, det...