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The arc instabilities in dc plasma torch result in non-homogenous treatment of material injected into the plasma jet. The improvement of this process is usually attempted by means of the reduction of arc fluctuations. This paper presents a new approach to overcome the plasma instabilities. The emphasis is to produce a pulsed laminar plasma jet combined with phased injection of liquid droplets. This is achieved by the particular design of the plasma torch which allows coupling two modes of the plasma oscillations, restrike and Helmholtz. It results in the pulsed arc jet which permits to synchronize the plasma with the suspension injection. This synchronization is obtained by a piezoelectric injector triggered by the voltage signal. The results are evaluated by time-resolved imaging technique and Time-Resolved Optical Emission Spectroscopy.
