IEEE TRANSACTIONS ON PLASMA SCIENCE, VOL. PS-9, NO. 4, DECEMBER 1981 J. L. Shohet, N. Talmadge, J. D. Treffert; F. Bauer, 0. L. Betan- court, P. Garabedian, J. A. Tataronis; J. G. Aspinall, L. Lidsky, P. A. Politzer, R. E. Potok; T. K. Chu, H. P. Furth, J. L. Johnson, C. Ludescher, and K. E. Weimer, Plasma Phys. Contr. Nucl. Fusion Res. 1980, Paper IAEA-CN-3 8/BB- 1. [4] W VII-A Team, in Proc. 8th European Conf Contr. Fusion Plasma Phys., Prague, 1977, vol. II, p. 73. [51 W VII-A Team, Max-Planck-Institute fur Plasmaphysik, Garching, 2/241, 1978. [6] W VII-A Team: D. V. Bartlett, G. Cannici, G. Cattanei, D. Dorst, A. Elsner, G. Grieger, H. Hacker, J. How, H. Jackel, R. Jaenicke, P. Javel, J. Junker, M. Kick, R. Lathe, F. Leuterer, C. Mahn, S. Marlier, G. Muller, W. Ohlendorf, F. Rau, H. Renner, H. Ringler, J. Saffert, J. Sapper, P. Smeulders, M. Tutter, A. Weller, E. Wur- sching, and H. Wobig, Nucl. Fusion, vol. 20, p. 1093, 1980. [7] J. Fujita, S. Itoh, K. Kadota, K. Kawahata, Y. 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KULCINSKI, D. T. ANDERSON, A. W. BAILEY, J. D. CALLEN, J. A. DERR, G. A. EMMERT, L. EL-GUEBALY, A. KHALIL, J. L. SHOHET, FELLOW, IEEE, D. K. SZE, R. C. SANDERS, AND J. A. TATARONIS Abstract-A preliminary design of a 5500 MWth modular stellarator power reactor, UWTOR-M, is presented. Discrete twisted coils are used in an Q = 3 configuration with maintainability as a prime consideration. The natural steliarator divertor is used for impurity control in conjunc- tion with innovative high performance divertor targets. A unique blan- Manuscript received June 4, 1981. This work was supported in part by DOE-OFE (Division of D&T) under Contract DE-AS02-78ET52048, and by the Division of Applied Plasma Physics Contract DE-AS02- 78ET5 3082. I. Sviatoslavsky, S. W. Van Sciver, G. L. Kulcinski, A. W. Bailey, J. D. Callen, G. A. Emmert, L. El-Guebaly, A. Khalil, D. K. Sze, and R. C. Sanders are with the Fusion Engineering Program, Nuclear Engineering Department, University of Wisconsin, Madison, WI 5 3706. D. T. Anderson, J. A. Derr, J. L. Shohet, and J. A. Tataronis are with the Torsatron/Stellarator Laboratory, University of Wisconsin, Madison, WI 53706. ket design is proposed which minimizes the overall tritium inventory in the reactor. Finally, a scheme for maintaining the first wall/blanket and other reactor components is discussed. INTRODUCTION ALTHOUGH the stellarator is one of the earliest proposed magnetic confinement concepts, having been invented in the early fifties, it was not until recently that it started to gain recognition in the fusion community. In large measure, this is due to recent encouraging experimental results which show that confinement in a stellarator does not degrade, but in fact improves, when the net plasma current is reduced to a near zero value [1]. These experimental results also verified that above a rotational transform of -0.3, the stellarator does not experience plasma disruption. 0093-3813/81/1200-0163$00.75 © 1981 IEEE 163