Research On Bubble Atomization Water Mist Fire Extinguishing System

Water mist can be used to replace halon series extinguishing agent,it is a new,efficient and clean water extinguishing agent.At present,the generation mode of water mist is mainly medium or high pressure system,which will increase the equipment installation and maintenance cost,and the suppression effect on flame of high pressure water mist is not ideal.Bubble atomization water mist is a kind of double-fluid water mist generation method,which only needs a low-pressure system to achieve the ideal water mist,moreover,it has the advantages of simple installation,low cost and good fire extinguishing effect.Based on the theoretical research on bubble atomizing technology,designed a double fluid atomizer,by changing the various structural parameters of atomizer to research various structural parameters and fluid parameters on the stability of the gas liquid two phase flow and the influence of the mixing length,design and build the bubble atomizing water mist fire extinguishing system and experimental measurement platform,the fog field particle size distribution and fire extinguishing effectiveness experiments,to research various structural parameters and fluid parameters on the droplet size distribution and the influence of fire extinguishing effectiveness,and analyze the fire extinguishing mechanism,to research the practicability of bubble atomized water mist fire extinguishing system.The results show that the gas-liquid and two-phase flow can be generated by the designed and built bubble-atomized water mist fire extinguishing system,but the mixing limit length is insufficient,so only one sprinkler can be supplied by one set of gas-liquid supply system.The determination of system parameters:The structure of atomizer adopts swirling flow liquid injection mode,with the diameter of gas injection hole 1.3 mm,the number of gas injection holes 12,the diameter of gas injection pipe 7 mm and the diameter of sprinkler 1.5 mm,can form the ideal width of the distribution of particle size of droplets and mixed cavity form the stability of the gas liquid two phase flow up to 40 cm,liquid injection pressure,the bigger the injection pressure is,the bigger the sprinkler hole diameter is,and the shorter the extinguishing time is.