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ukaea / PROCESS

PROCESS is a systems code at UKAEA that calculates in a self-consistent manner the parameters of a fusion power plant with a specified performance, ensuring that its operating limits are not violated, and with the option to optimise to a given function of these parameters.
https://ukaea.github.io/PROCESS/
MIT License
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Discrepancy in H factor #881

Closed jonmaddock closed 4 months ago

jonmaddock commented 5 years ago

In GitLab by @mkovari on Jul 11, 2019, 14:57

According to the 2019 baseline Plasmod output (K:\Power Plant Physics and Technology\PROCESS\DEMO Baseline Runs\2019) the H-factor is only 0.892: 

Computed H factor according to ITER 98 y2 elmy H mode     (loss%H)            0.892

and this is repeated in the main part of the output:

Confinement scaling law      IPB98(y,2)           (H)
Confinement H factor                                      (hfact)             0.892

However, this value is obviously too small, and it contradicts the table of H-factors:

 ***************************** Energy confinement times, and required H-factors : *****

    scaling law              confinement time (s)     H-factor for
                                 for H = 1           power balance

 IPB98(y,2)           (H)          5.440                   1.192

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jonmaddock commented 2 years ago

In GitLab by @wg7580 on Jul 20, 2022, 09:15

@mkovari is this something that is still an issue? If it is i can try and look into it

jonmaddock commented 2 years ago

In GitLab by @ajpearcey on Aug 5, 2022, 15:26

So this occurring because the Energy confinement times, and required H-factors part of the output is printed in the subroutine igmarcal where it computes the confinement times from the subroutine pcond. So it is ignoring the PLASMOD part of the calculation and in addition is also using the PROCESS definition of the P_loss which maybe different from PLASMOD.

If the value of 0.892 that PLASMOD produces is correct or not is not something I can easily answer.

j-a-foster commented 4 months ago

@mkovari was this a PLASMOD-specific problem or a wider H-factor calculation problem?

mkovari commented 4 months ago

It was purely a Plasmod problem.