Search found 23 matches

by daniel.wojtaszek
Wed Jul 24, 2019 5:55 pm
Forum: Bugs, problems, questions & feeback
Topic: power output fluctuations in coupled simulation
Replies: 3
Views: 651

Re: power output fluctuations in coupled simulation

Thanks.

It turns out that a case where the temperature drops and the density remains unchanged also resulted in the fluctuations, as did the case where density decreases and temperature remains unchanged. So our hypothesis about density change being the issue is seemingly incorrect.

Cheers.

Dan
by daniel.wojtaszek
Thu Jun 13, 2019 10:13 pm
Forum: Bugs, problems, questions & feeback
Topic: power output fluctuations in coupled simulation
Replies: 3
Views: 651

power output fluctuations in coupled simulation

I'm running a coupled simulation of a molten salt type reactor with temperature and density feedback. The power output calculated by serpent seems ok until the temperature increases and density decreases, when the power starts to bounce up and down as shown in the attached image. The issue persists ...
by daniel.wojtaszek
Wed May 15, 2019 6:46 pm
Forum: General
Topic: format of .storeprec file
Replies: 8
Views: 2063

Re: format of .storeprec file

I've been looking at particlesfromstore.c and noticed that data from the .storepmeshA/B and .storeprecA/B files may both be read during the same PrecursorsToStore() function call. In this case which data is used in the calculation?

Cheers.

Dan
by daniel.wojtaszek
Wed May 15, 2019 6:23 pm
Forum: General
Topic: format of .storeprec file
Replies: 8
Views: 2063

Re: format of .storeprec file

Line 206 in precursorstostore.c (serpent 2.1.29) indicates that the number of double sized values written to the file for each particle is PARTICLE_BLOCK_SIZE - LIST_DATA_SIZE, which is 41 - 4 = 37 double values written to the file per particle.
by daniel.wojtaszek
Tue May 14, 2019 2:41 pm
Forum: General
Topic: format of .storeprec file
Replies: 8
Views: 2063

Re: format of .storeprec file

Thanks for your very helpful response.

Cheers!

Dan
by daniel.wojtaszek
Mon May 13, 2019 8:52 pm
Forum: General
Topic: format of .storeprec file
Replies: 8
Views: 2063

Re: format of .storeprec file

Thanks Ville. Am I correct in assuming that, except for the first iteration, the data from these .storeprec files are read by serpent at the beginning of each coupled iteration in order to continue the calculation? In other words, modifying the position of each dnp in these files after an iteration ...
by daniel.wojtaszek
Thu May 09, 2019 5:54 pm
Forum: General
Topic: format of .storeprec file
Replies: 8
Views: 2063

format of .storeprec file

What is the format of the data that is stored in the .storeprec files that are created during coupled mode execution?

Cheers.

Dan
by daniel.wojtaszek
Wed May 08, 2019 2:40 pm
Forum: Bugs, problems, questions & feeback
Topic: [Issues] Power normalization in transient mode
Replies: 11
Views: 3092

Re: [Issues] Power normalization in transient mode

Further to my previous post about set opti 2 and its effect on power normalization, I've just discovered that set opti 1 also affects power normalization. This issue occurs with serpent 2.1.29. set opti 4 fixed the issue. I haven't tried set opti 3 yet.
by daniel.wojtaszek
Tue Apr 09, 2019 3:30 pm
Forum: Bugs, problems, questions & feeback
Topic: Reactivity consistency issue in time-dependent simulation
Replies: 7
Views: 1187

Re: Reactivity consistency issue in time-dependent simulation

It looks like the issue was that the population was too small. Setting the population to 50e6 resulted in a much smaller discrepancy between static and time-dependent calculations.

Thanks for your responses.

Cheers.
by daniel.wojtaszek
Fri Apr 05, 2019 7:57 pm
Forum: Bugs, problems, questions & feeback
Topic: Reactivity consistency issue in time-dependent simulation
Replies: 7
Views: 1187

Re: Reactivity consistency issue in time-dependent simulation

The proximity of my static system to keff = 1.0 depends on which serpent output you go by. According to ana_keff and col_keff it's 1 pcm supercritical, whereas ABS_keff and IMP_KEFF is 18 pcm subcritical. Yes, the first timestep of the transient is about 200 - 300 pcm subcritical. This effect also o...