PROCESSES AND PROPERTIES OF ELECTRIC-ARC STABILIZED BY WATER VORTEX

Experimental investigation of electric are stabilized by water vortex was carried out in a de are plasma torch for power range 90-200 kW. Vo lt-ampere characteristics of the are as well as power balance were det ermined separately for the part of the are column stabilized by water and for the remaining part between the nozzle exit and external anode. Temperature of are plasma close to the nozzle exit was determined by emission spectroscopy. Negatively biased electric probes in ion collec ting regime were used for determination of plasma flow velocity, The m easured temperatures up to 27 000 K, and velocities up to 7 km/s are h igher than the values commonly reported for plasma torches with de arc s stabilized by a gas flow, Mass and energy balances within the are ch amber were determined from the experimental results, The radial transp ort of energy by radiation was identified as a decisive process contro lling are and plasma properties, The balance of radial energy transpor t was studied. The ratio of energy spent for evaporation of water to t he energy absorbed in the evaporated mass is very low in water stabili zed are. This is the principal cause of high plasma temperatures and v elocities found by the measurements.