Plasma and Fusion Research
Volume 1, 010 (2006)
Rapid Communications
- Graduate School of Energy Science, Kyoto University
Abstract
The effects of toroidal field ripples on bootstrap current in the low collisionality regime in tokamak plasmas are discussed by using an asymptotic expression of the bootstrap current. When the toroidal field ripple is 1-3%, an 8-15% reduction of the bootstrap current is predicted in a tokamak plasma having q = 1.8 and εt = 0.3. If we fix the ripple ratio, dependence on the number of toroidal field coils is negligible when the number is more than 15. These results suggest that the effect of the toroidal field ripple on the bootstrap current is particularly important when the pressure gradient is steep near the plasma edge.
Keywords
bootstrap current, ripple, tokamak, neoclassical theory, low collisionality regime
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This paper may be cited as follows:
Yuji NAKAMURA, Plasma Fusion Res. 1, 010 (2006).