Measurement of liquid particle concentrations in a free jet flow

An experimental model was developed to quantify the concentration of liquid particles in a two-phase jet induced by a coaxial injector. The particles tested here, having 40 μm as mean diameter, are generated and transported by an air flow. The concentrations of particles are calculated through measurements of their characterizing parameters such as their velocities, their sizes and their crossing frequencies in the probe volume of a laser-Doppler apparatus. For a water column flowing with a velocity of 1.4 m/s and sprayed by an air stream with initial injection velocity of 80 m/s, the concentration of the liquid particles measured in six stations downstream the injection orifice varies from 70 g m −3 to 24 g m −3. The obtained concentrations are in good agreement with those obtained, directly by the use of the isokinetic sampling method.