A SHOCK TUBE DEVICE FOR PELLET INJECTION. PRELIMINARY EXPERIMENTAL RESULTS
The excellent results, obtained in the ISX experiment, concerning the efficiency of refuelling by means of pellet injection, the feasibility of fuel deposition in hot, low diffusion regions of the plasma, together with the possibility of controlling the density profiles by suitably acting on the size and on the injection speed of the pellet, make the injection of pellets both an advantageous diagnostic tool and the most likely candidate for refuelling fusion reactors based on the magnetic confinement of the plasma. Though the interesting velocity range of 1 km/sec has been achieved with simple gun-type injectors, application of this refuelling method to power reactors depends, to a large extent, on the development of more sophisticated technologies of pellet acceleration. In the present work some preliminary results, obtained with a pneumatic acceleration device driven by a piston shock tube, are presented. In principle, with this method an almost constant acceleration can be given to the pellet, achieving velocities in excess of 5 km/sec with a launching barrel of reasonable length (of the order of 50 cm). Moreover, this device requires a small mass of propellant (hydrogen or helium), thus minimizing the total gas flow to be evacuated by the pumping system. Tests have been performed by shooting nylon pellets of 1.5 mm diameter; velocities in excess of 2 km/sec have been achieved.
Bibliographic Reference: WORKSHOP ON DIAGNOSTICS FOR FUSION REACTOR CONDITIONS, VARENNA, COMO (ITALY), SEPT. 6-17, 1982, PP. 249-257 351 P., 1983, ISBN 0-08-031161-X WRITE TO PERGAMON PRESS LTD., HEADINGTON HILL HALL, OXFORD OX3 OBW (ENGLAND), PRICE: UKL 47, (EUR 8351 EN).
Record Number: 1989123105200 / Last updated on: 1987-01-01
Available languages: en