Research On Rotating Core Structure Of High Pressure Water Mist Nozzle And Its Tests Of Fire Suppression

High-pressure water mist has the advantages of environmental protection,fast fire extinguishing,low water consumption.It is the main substitute for halon fire extinguishing agent.Domestic and foreign scholars mainly focus on the research of water mist fire extinguishing test and fire extinguishing mechanism,and little research on the structure of high pressure water mist nozzle.In this paper,the key components of the seven nozzle combination nozzles are studied.Firstly,the influence of various structural parameters of the core on the characteristics of the mist field is qualitatively analyzed to determine the processing parameters of the core structure.(1)I designed and machined a series of core components that were made up the water mist nozzle,including 5 kinds of aperture nozzles,4 kinds of guide vane guide columns and 3 kinds of guide troughs.The 120 kinds of nozzles were made up of these components.They were performed by cold experiments.The atomization effect,atomization angle,nozzle exit droplet velocity and oil droplet surface droplet velocity of the nozzle were studied.Several ideal atomization nozzle structures with centrifugal and swirl were screened out through experiments.(2)12 kinds of multi-nozzle combined with water mist nozzles were assembled by myself,and the hot state experiments of multi-nozzle were carried out to measure the fire extinguishing time and protection radius of the combined nozzles.The parameters of the optimal water mist nozzle were determined by experiments as the angle of the guide groove is 30°,the depth of the guide groove is 1.0mm,and the nozzle diameter is 0.6mm.(3)The study on the extinguishing of oil pool fire by water mist was carried out,and the effects of working pressure,location of fire source,fog flux and ventilation conditions on the fire extinguishing effect were analyzed.The results show that increasing the working pressure of the water mist system will improve the fire extinguishing efficiency as a whole,but it does not change linearly.The location of the fire source relative to the nozzle has a significant effect on the fire extinguishing effect.The farther the fire source is away from the center of the nozzle,the longer the fire extinguishing time is.The highest area of the fog flux is generally distributed around the center of the nozzle,and the center of the nozzle is often not the area with the highest fog flux.Ventilation has a certain impact on the water mist fire extinguishing,and low-speed ventilation is conducive to the fire extinguishing of water mist.