Nonlinear gyrofluid test cases

Below are several more GF data points for our test cases. These runs were all using a theta domain from (-pi,pi) to match Andris's results.

GF Gryffin: k_theta,max gamma omega_r R/L_Tcrit chi_i phi^2
DIII-D base 0.30 0.11 -0.34 8
DIII-D base + 30% 0.35 0.19 -0.47 10
DIII-D base - 30% 0.20 0.041 -0.14 5
NTP test 0.35 0.14 -0.46 7
Dimits PRL 0.35 0.19 -0.42 9
shat = 0
zero out 0,0 0.30 0.11 -0.34 30

The PRL case is indeed very similar to the DIII-D base case, as Bill suggested.

The DIII-D base -30% case is in marked contrast to Andris's result. I checked the growth rates for this case with a kinetic code. Our growth rates are only about 20% high at these parameters, indicating that this point is far enough from marginality that the GF inaccuracies in the threshold are not playing a big role here.

A few other observations which may already have been discussed:

Andris's values in Scott's table for "PRL" and "NTP" don't seem to match those in Andris's PRL Fig. 2a. Assuming that the x-scale is off by 10, I think that the "PRL" point is at qR/L_T=1.2 on this graph, and has chi_hat=0.6. The "NTP" point is at qR/L_T=2.4 and has chi_hat=1.0. So the ratio of NTP/PRL should be about 1.7 but in the table it's 2.6. Which one is missing the 1.5?

The Linear FULL value of R/L_T_crit in Scott's table looks way off to me.


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