Fast-opening, high-throughput gas valve and application for inertial fusion energy R&D

A fast-opening, high-throughput gas valve and its application to inertial fusion energy (IFE) research and development are described. The valve is a pilot type with two stages of active components. The pilot or first stage section is magnetically driven and equipped with a 4.2-mm-diam orifice. The pilot valve is energized to initiate operations and dumps gas from the upstream section of the second stage to the main valve outlet, and the resultant pressure differential across the large (22.3-mm-diam) output orifice seat causes mechanical activation of the second stage. Both stages are equipped with hard polyimide stem tips and springs for sealing. The valve has been operated reliably with helium gas at pressures in the range of 4–35 bar and frequencies up to 6 Hz, with maximum flow rates of ≈106 Torr l/s. The valve was developed to provide helium propellant gas for accelerating IFE targets to speeds up to 400 m/s in an experimental injector system under construction by General Atomics.