UNCERTAINTY Calculation

[MarcoFabbri]

Dear forum,

I am running some activation simulations with FISPACT-II.

Unfortunately, I am struggling with the following simulation when I try to impose UNCERTAINTY 2 to have a complete path analysis (by the way using UNCERTAINTY 0 it works).
https://user.iter.org/filesharing/?uid= ... 3f4fb44324

Looking into the log files seems that some reaction channel is missing, right? Should I populate the pathways? How?

I hope you can help on this.

Thanks in advance,

All the best,
Marco

[Michael Fleming]

Dear Marco,

FISPACT-II adds data to the pathways analysis when one of the solver-initation keywords (ATOMS, SPECTRUM or STEP) are used. In this simulation the various irradiation steps do not have any of these keywords and the first case has 0 flux:

Code: Select all

<< ----- STEP#1 - DD 2.68 MW * 2y ----- >>
FLUX 5.36E+5
TIME 2 YEARS
<< ----- STEP#2 - DT 20.6 MW * 10y ----- >>
FLUX 4.12E+6
TIME 10 YEARS
<< ----- STEP#3 - DT 0 MW * 0.667y ----- >>
FLUX 0
TIME 0.667 YEARS SPEC

This results in the code attempting to handle pathways where there are no reactions, causing an error. To solve this simply add in one of those keywords during the irradiation steps, such as:

Code: Select all

<< ----- STEP#1 - DD 2.68 MW * 2y ----- >>
FLUX 5.36E+5
TIME 2 YEARS STEP
<< ----- STEP#2 - DT 20.6 MW * 10y ----- >>
FLUX 4.12E+6
TIME 10 YEARS STEP
<< ----- STEP#3 - DT 0 MW * 0.667y ----- >>
FLUX 0
TIME 0.667 YEARS SPEC

Let me know if this works for you.

Best regards,
Michael