EFDA-JET-CP(13)03/45

Nonlinear Saturation of the Toroidal Alfvén Eigenmodes Computed with the VENUS+df, HAGIS and KINX codes

The successfull benchmarking of the linear growth stage of fast particle driven TAE with a broad variation of numerical models by the ITPA Energetic Particle Topical Group for an n = 6 Toroidal Alfvén Eigenmode (TAE) number was described in [1]. In this paper, the second stage in the wave evolution ­ the non-linear saturated state - is computed for the same n = 6 test case (Section 2) and also for an n = 4 TAE in JET Pulse No: 40214 (Section 3). The fixed spatial structure of TAE modes hmn(s) (s = (r/a)2 is in this paper a normalised toroidal (or can be also a poloidal in some codes) flux function, a is a minor plasma radius) is calculated with the KINX and MISHKA codes. The fast particle dynamics, TAE growthrates and wave saturation levels are computed with the HAGIS and VENUS+df orbit following codes.
Name Size  
EFDC130345 621.14 Kb