Atomizing Nozzle/Fine Mist Nozzle

The Navy has developed and successfully tested a nozzle developed at the Naval Air Warfare Center Aircrafat Division Patuxent River, MD and Lakehurst, NJ by Joseph Wolfe. The nozzle, shown in figure 1, uses air to push water through a restricted convergent region followed by an expanded divergent region of the nozzle. The rapid expansion of the water and gases in the divergent region causes the water to break up and be atomized into droplets of sizes on the order of 10 to 100 micrometers. A secondary patent describes a completely portable, relatively simple system that is self pressurized with carbon dioxide gas that is generated by a chemical reaction with a bicarbonate compound. Summary of Benefits Simple design; Nozzle can be fabricated using standard machining methods and using a variety of metals or composite/plastic materials; Larger, hand held nozzle systems have been successfully tested and demonstrated at the Pittsburgh Fire Academy by firefighters; Fires on a three foot diameter oil pan extinguished in 15 seconds or less; Atomized water droplets have forward momentum, unlike other misting units; Relatively large nozzle orifice does not clog or become obstructed from dirt or debris in the water; Since there is minimal back momentum and a smaller garden hose size is used, nozzle can be easily held in one hand while in operation - unlike conventional nozzles that require two hand operation and many times more than one firefighter to maintain control of the nozzle and hose figure 2; Minimal water usage of approximately four gallons/minute compared to over 150 gallons/minute for conventional nozzles, translating into minimal water damage; thus reducing repair costs and insurance claims. 2006 FLC National Meeting Award Winner