Development of the high speed pellet injector for ignitor

ENEA and Oak Ridge National Laboratory (ORNL) are collaborating on the development of a four barrel, two-stage pneumatic injector for the Ignitor experiment, featuring two innovative concepts: (i) the proper shaping of the propellant pressure pulse to improve pellet acceleration, and (ii) the use of fast closing (< 10 ms) valves to drastically reduce the expansion volumes of the propellant gas removal system. Two independent sub-systems have been built and tested separately by ENEA and ORNL. The ENEA equipment has then been shipped to Oak Ridge, where testing of the two coupled systems have started during the last year. The results of the first two short experimental campaigns, jointly carried out by ENEA and ORNL teams (May 12-16 and December 15-19 2008), as well as the latest advancement of this project will be reported.