Optical investigation of high-speed aerosol-microjets

Aerosol-jets are generated by the expansion of an aerosol-gas mixture from different types of micro-nozzles. The particle velocity is measured by means of a Fabry-Perot laser Doppler anemometer, whereas the geometrical structure of the jet will be investigated by direct optical observation. Comparative measurements show that Laval-nozzles are more suitable for the generation of rapid, intense aerosol-jets than simple orifices, because the internal energy of the carrier gas may be transformed more perfectly into one-directional kinetic energy. Moreover, the particles gain high velocities due to the smooth acceleration process. (author)