Flow dynamics and microparticles acceleration in the electrothermal launcher.

Application of electrothermal launchers for obtaining powder materials coat ings with improved values of density end adhesion requires formation of the gas flow region, immediately following behind the shock nave, where microp articles are being caught into acceleration A method of such region forming by means of the shock wave space and time shaping is presented. The flow d ynamics analysis on the basis of a numerical model which was carried out fo r the case of two gaps in the launcher discharge unit, has shown that it is possible to accelerate microparticles up to very: high velocities (2 km/s and higher) with simultaneous control of their temperature and to increase substantially the launcher efficiency. Measurements with the experimental e quipment allowed us to determine dynamic parameters of flows, the velocity and extension of the shock-compressed region as well as velocities of the s hock-waves and main flow region. Registration of plasma flows radiation spe ctra permitted to determine their temperature. The obtained experimental re sults are in good correlation with computer simulation data.