IAEA Fusion Energy Conference 2010

Proceedings of the 23rd IAEA Fusion Energy Conference
Daejeon, 11-16 October 2010

Organized by the International Atomic Energy Agency
and hosted by the Government of the Republic of Korea


(THC/P4-10) Alpha Particle-Driven Toroidal Rotation in Burning Plasmas

M. Honda1), T. Takizuka1), K. Tobita1), G. Matsunaga1), A. Fukuyama2), T. Ozeki1)
1) Japan Atomic Energy Agency, Naka, Japan
2) Graduate School of Engineering, Kyoto University, Kyoto, Japan

Abstract.  The mechanism of a torque intrinsically produced by alpha particles and the subsequent possibility to create significant toroidal rotation and shear are investigated. In DEMO plasmas, an orbit-following Monte Carlo code OFMC predicts that the profile of a collisional torque is influenced near the magnetic axis by a reversed magnetic shear configuration, while that of a j×B torque is not. It is found that the gradient of the source profile of alpha particles produces the co-directed collisional torque and a counter-directed j×B torque, and both torques virtually cancel each other out in the central region of the plasma. A non-negligible torque shear and resulting toroidal rotation in the co-direction are obtained in a weakly reversed-shear configuration, but the estimated rotation velocity is below the threshold to stabilize resistive-wall modes through intrinsic alpha-driven torque alone.

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