Study of a transaugmented two-stage small circular-bore railgun for injection of hypervelocity hydrogen pellets as a fusion reactor refueling mechanism

Journal Article · Wed Jan 01 04:00:00 EST 1997 · IEEE Transactions on Magnetics

DOI:https://doi.org/10.1109/20.560083· OSTI ID:462699

Tompkins, M W; Anderson, M A; Feng, Q; Zhang, J; Kim, K ^[1]

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1. Univ. of Illinois, Urbana, IL (United States)

Injection of hypervelocity hydrogen pellets has become widely accepted as the most effective means of refueling magnetically confined fusion reactors. Pellet velocities on the order of 10 km/s are desired and hydrogen pellet erosion during acceleration must be minimized. It is important to maintain uniform bore surfaces during repetitive shots, implying that, if a railgun is to be used to accelerate the pellets, damage to the sidewalls and rails of the railgun due to local heating must be limited. In order to reduce the amount of power dissipated within the bore and increase the propulsive force generated by the plasma-arc armature while minimizing losses due to pellet, rail, and sidewall ablation, the authors have employed a magnetic field transaugmentation mechanism consisting of a two-turn pulsed electromagnet. The two-stage gun consists of a light-gas gun which accelerates a 4- to 5-mg pellet to a speed around 1.2 km/s and injects it into the plasma-arc armature railgun. Currently, they have achieved a final output velocity for a hydrogen pellet of 2.11 km/s with a time-averaged acceleration of 4,850 km/s{sup 2} using a 58-cm railgun pulsed with a peak rail current of 9.2 kA and 28.0 kA of transaugmentation current. This paper will present a description of the hydrogen-pellet-injector railgun system, a discussion of the data on hydrogen pellet acceleration, and projections for future systems.

• DOE Contract Number: FG02-84ER52111
• OSTI ID: 462699
• Report Number(s): CONF-9604202--
• Journal Information: IEEE Transactions on Magnetics, Journal Name: IEEE Transactions on Magnetics Journal Issue: 1Pt1 Vol. 33; ISSN IEMGAQ; ISSN 0018-9464
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
DESIGN
ELECTROMAGNETS
PELLET INJECTION
PERFORMANCE
POWER LOSSES
RAILGUN ACCELERATORS
THERMONUCLEAR REACTOR FUELING