J. Plasma Fusion Res. SERIES, Vol'1 (1998) 414-4'17 New Repetitive Pellet Iniectors for steady state Fuelling VINIARlgor,SUDOShigerul*,SKOBLIKOVSergey'UMOVAlex'

Two new repetitive injectors providing a steady state plasma fuelling by an unlimited number of pellets have been designed for fusion devices. Several thousands of hydrogen pellets of 2 mm diameter each were made and accelerated to 0.8 km/s at the rate of I Hz and 2Hz by an injector equipped with a screw extruder. The extruder had a 5 cm3 working volume and was used for a continuous extrusion of over 250 cm3 of solid hydrogen with an average production rate of 65 mm3,/s. Another injector con-sisted of ten pipe guns with porous units producing solid hydrogen pellets for 5-9 s in every barrel. Over one thousand hydrogen pellets of 2.4 mm diameter were accelerated to 1 km,/s in this injector. The injector designs and experimental results are presented' Keywords: plasma, fuelling, pellet, injector, extruder, pipe gu