Characterization of a Two Dimensional Air Curtain

A physical separation between two environmental can be useful realized by means of a two dimensional gaseous jet, often called air curtain. The typical applications of this kind of devices concerned the physical separation of the adjacent environments with different pollutant levels. In particular the paper investigate the behavior of a rectangular submerged jet in rejecting dusty air from a powder zone and a clean one. The investigated jet was generated by means of a rectangular nozzle with two discharge areas respectively of 0.02x1.0 and 0.04x1.0 m ad comparing the result with previous one realized with a nozzle of 0.01x1.0 m as discharge area. The dust has been simulated using atomized distilled water dispersed in a cloud of small droplets, sprayed transversally the air curtain. Experiments have been performed running the air curtain at Reynolds Number(Re) ranging from 4500 to 25500, for all the nozzle’s configuration investigated. The water spray has been characterized using a TSI single component fiber optics Phase Döppler Particle Analyzer (PDPA), and the air curtain has been investigated by means of a Particle Image Velocimetry (PIV) technique. The amount, size distribution and velocity of the droplets cloud, able to cross the air curtain, was measured, obtaining, as main result, the dependence of the amount of droplets passing the barrier as a function of the Re and thickness of the air curtain.