Abstract
Shear flow stabilization of edge turbulence leads to self-organized high (H) confinement modes in tokamak plasmas. Thus understanding the mechanisms for generation of shear/zonal flow and fields in finite β plasmas is an important area of research. A brief review of various mechanisms for shear flow generation and discussion of our recent theory which yields a criterion for bifurcation from low to high (L-H) confinement mode is presented. The predicted threshold based on this parameter shows good agreement with edge measurements on discharges undergoing L-H transitions in DIII-D with ▽B both towards and away from the X-point, as well as for pellet induced H-modes.
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Guzdar, P.N., Kleva, R.G., Groebner, R.J., Gohil, P. (2005). Transition to Self-Organized High Confinement States in Tokamak Plasmas. In: Burton, W., et al. Nonequilibrium Phenomena in Plasmas. Astrophysics and Space Science Library, vol 321. Springer, Dordrecht. https://doi.org/10.1007/1-4020-3109-2_10
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DOI: https://doi.org/10.1007/1-4020-3109-2_10
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