Estimations of some parameters of the discharge chamber of powerful electric discharge launcher

Abstract

Results of the discharge chamber of electric discharge launcher (EDL) testing, aiming at the study of heat transfer, are presented. Test conditions are: initial He pressure 5-40 MPa, discharge chamber volume 1400 cu cm, current less than 1.5 MA, energy stored 1.3 MJ, circuit own frequency 1 kHz. To simulate gas heating in the EDL discharge chamber and to use high speed camera, a diagnostic discharge chamber was made. Based on the arc dynamics study in the diagnostic discharge chamber, temperature and conductivity estimations of the arc channel were carried out for the EDL chamber. Measured pressure and conductivity correspond to temperatures arcs burning in copper vapors and in He. Since the pressure equilibrium in the volume was reached, acoustic oscillations may be used to evaluate gas temperature. Moving arc causes shock waves registered by pressure transducers, placed along the discharge chamber length, and by a high-speed camera. Arc-to-gas energy transfer efficiency rises along with the initial He pressure increase and reaches 90 percent for 40 MPa. Both shock wave propagation and arc radiation absorption seem to yield to this rise. (Author)