Skip to Main Content
Your organization might have access to this article on the publisher's site. To check, click on this link:http://dx.doi.org/+10.1116/1.575822
In the past several years, steady progress has been made worldwide in the development of high‐speed hydrogen pellet injectors for fueling magnetically confined plasmas. Several fueling systems based on the conventional pneumatic and centrifuge acceleration concepts have been put into practice on a wide variety of toroidal plasma confinement devices. Long‐pulse fueling has been demonstrated in the parameter range 0.8–1.3 km/s, for pellets up to 6 mm in diameter, and at delivery rates up to 40 Hz. Conventional systems have demonstrated the technology to speeds approaching 2 km/s, and several more exotic accelerator concepts are under development to meet the more demanding requirements of the next generation of reactor‐grade plasmas. These include a gas gun that can operate in tritium, the two‐stage light gas gun, electrothermal guns, electromagnetic rail guns, and an electron‐beam‐driven thruster. Although these devices are in various stages of development, velocities of 3.8 km/s have already been achieved with two‐stage light gas guns, and the prospects for attaining 5 km/s in the near future appear good.