## 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.

--Mike

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