AbstractA parameter regime is sought which simultaneously fulfils the various physics constraints in the case of ITER-grade tokamaks, and a consistency analysis code is applied. It is found that, if the energy confinement time reaches 1.6 times that predicted by the L-mode scaling law, a Q-value of about 4 is possible for full current-drive operation at an input power Pin of 100 MW (Q is the ratio of fusion output to Pin). In the hybrid operation, where half of the curent is inductively sustained, Q approaches the value 15 for this given circulating power. If the L-mode only is realized, Q is about 1.5 for Pin ≅ 100 MW.
The potential of driven tokamaks as thermonuclear reactors