PLASMA COAXIAL DISCHARGE EFFICIENCY

A coaxial discharge system with negative central electrode has been used to study the plasma current sheath and the ejected plasma parameters. Results showed that the plasma sheath velocity reached 5 x 10 cm/s at the muzzle. The ejected plasma velocity in the expansion chamber varied with position z according to the relation V = k • z40.', while the temperature and the density changed as: T = To • z"•e & N = No •'12, respectively. It has been detected that the plasma current sheath and the ejected plasma are accompanied with an induced axial magnetic field, which indicated that the plasma rotates within its propagation. The input energy from the capacitor bank to the coaxial discharge system was 196 J, (Joule), the energy gained by the plasma as kinetic energy was 17 J, while the plasma internal energy was 5.6 J. Hence 8% of the energy was gained as a kinetic drift of the plasma,