Impurities peaking factor

[jonmaddock]

In GitLab by @skahn on Dec 9, 2020, 12:13

Description

Neoclassical effects can drive strong impurity accumulation if not flushed away by current drive system or turbuence. This effect can be captured a posteriori by adding a impurity peaking factor. As the neocalassical transport term depends on $Z^2$, the peaking should be different for each species.

The same type of arguments are also valid for the pedestal transport, as the source if generally on the divertor / FW or any gas puffing systems

Action list

• [ ] Setup a peaking factor array like fimp (f_peak_imp) defined as the $\frac{n_\mathrm{imp}\left(0\right)}{n_\mathrm{imp}\left(ped\right)}$
• [ ] Setup a pedestal density factor defined as $\frac{n_\mathrm{imp}\left(ped\right)}{n_\mathrm{imp}\left(sep\right)}$. Please note that this factor should be allowed to go above 1 as the main impurities sources are outside the plasma.
• [ ] Update the fusion power calculations
• [ ] Update the line radiation calculation
• [ ] Does the brhem. and sync. needs to be updated ?
• [ ] Analyse the changes on our favourite run
• [ ] Document this on the md pages

Ref : @stuartmuldrew, @skahn, @mkovari and @ajpearcey

Best regards
Seb

[jonmaddock]

In GitLab by @mkovari on Dec 9, 2020, 16:09

I would like to have a better technical understanding before moving forward. Can you think of someone to talk to?