Studies on a stellarator reactor of the Helias type : The power balance
The power balance of a Helias reactor is analysed using empirical scaling laws which describe current stellarator experiments. Since neoclassical transport in Helias configurations is not prohibitive to ignition, anomalous transport determines the parameters of the ignited state. In the following study the plasma profiles are taken as given and the power balance with an external heating power is evaluated numerically. Three empirical scaling laws, LHD scaling, Gyro-Bohm scaling and Lackner-Gottardi scaling are extrapolated to reactor parameters. Present experiments (Wendelstein 7-AS, ATF, Heliotron E and CHS) can be described by these scaling laws. LHD scaling and Gryo-Bohm scaling do not satisfy the ignition conditions; an improvement of confinement is necessary. However, Lackner-Gottardi scaling does meet the ignition condition, and the operating window of the Helias reactor was found in the following regime: major radius 20 m, average plasma radius 1.6 m, magnetic field 5 T, density n(0) = 3 - 4 x 1.0 E20/m3 and temperature T(0) approximately equal to 15 - 17 keV. The fusion output power is 2.5 - 3.0 GW and the average value of beta = 4 - 5 %. This lies within the MHD-stability limits of a Helias configuration. The effects of various parameter variations on the power balance (isotope effect, alpha-particle content, major radius, magnetic field) are also investigated.
Bibliographic Reference: Report: IPP 2/318 EN (1993) 23 pp.
Availability: Available from Max-Planck-Institut für Plasmaphysik, 8046 Garching bei München (DE)
Record Number: 199311119 / Last updated on: 1994-11-29
Original language: en
Available languages: en