Electrically Charged Water Mists for Extinguishing Fires

摘要

A brief experimental fire suppression study found that electrical charging of water mist can substantially reduce both the time and the amount of water required to extinguish a pool fire. Another benefit of charging was an increased spraying angle, which occurs even for low pressure sprays. It was also found that much lower voltages than reported by other workers can be very effective in charging the mist and extinguishing fires. The specific objectives of the study were to: (1) compare the motion of charged and uncharged water mist droplets near a flame and (2) determine the reduced time for fire extinguishment due to electric charging of the water mist. The current program addressed ceiling sprinkler extinguishment of compartment fires, and the same principles should hold for aircraft engine nacelle fires. The main technical problem encountered was achieving a uniform distribution of water mist over a significant surface area both with and without charging. Promising results were obtained despite this difficulty which can be corrected with additional work. This study has achieved the objectives of element 4d of the Next Generation Fire Suppression Technology Program and additional funding should be provided to optimize the technology and demonstrate its effectiveness on larger scale fires.