STATIONARY HIGH-PERFORMANCE DISCHARGES IN THE DII-D TOKAMAK.

Download or read book STATIONARY HIGH-PERFORMANCE DISCHARGES IN THE DII-D TOKAMAK. written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A271 STATIONARY HIGH-PERFORMANCE DISCHARGES IN THE DII-D TOKAMAK. Discharges which can satisfy the high gain goals of burning plasma experiments have been demonstrated in the DIII-D tokamak under stationary conditions at relatively low plasma current (q[sub 95]> 4). A figure of merit for fusion gain ([beta][sub N]H[sub 89]/q[sub 95][sup 2]) has been maintained at values corresponding to!= 10 operation in a burning plasma for> 6 s or 36[tau][sub E] and 2[tau][sub R]. The key element is the relaxation of the current profile to a stationary state with q[sub min]> 1. In the absence of sawteeth and fishbones, stable operation has been achieved up to the estimated no-wall[beta] limit. Feedback control of the energy content and particle inventory allow reproducible, stationary operation. The particle inventory is controlled by gas fueling and active pumping; the wall plays only a small role in the particle balance. The reduced current lessens significantly the potential for structural damage in the event of a major disruption. In addition, the pulse length capability is greatly increased, which is essential for a technology testing phase of a burning plasma experiment where fluence (duty cycle) is important.