Study On Modification And High Pressure Discharging Of Fire Water

Facing the present situation of high accident frequency, backwardness of safety standard and the serious lag of fire protection technology, in this paper, propellant fire was taken as an example to study the fire-fighting technology of energetic material.Firstly, by analyzing the steady state burning mechanism of propellant, mechanisms of the flameout of propellant were proposed:cooling the flame, diluting the concentration of combustible gas, reducing the number of active radical and making the flame deviate from propellant.Secondly, an experimental research of mimicking the fire of propellant, the results show that:reducing the size of propellant and increasing the accumulation of propellant on unit area can increase the fire spread rate of propellant. A theoretical critical condition of the quenching of propellant combustion was established based on the results and the theory of hot ignition. Then a method of the quenching of propellant fire was brought forward:using high speed sprinkler system to discharge the fire water with decomposable flame retardant.Thirdly, the modification and property characterization of fire water were studied based on the enhancement of its flow property, cooling performance, frost resistance and corrosion resistance. The results show that the modified fire water can fulfill the standard requirements; its endothermic ability is improved and it can effectively suppress A type fire.Finally, a high-pressure discharging test platform of modified fire water was designed and built. The difference of discharging effectiveness between tap water and modified fire water was given by experiment. And several factors such as filling pressure, sprinkler type and nozzle aperture were considered in the experiments. The results show that the discharging flow and discharging velocity of modified fire water are higher than the discharging flow and discharging velocity of tap water under the same condition. In other words, the modified fire water is able to finish spraying in a shorter time. With the increase in filling pressure, the discharging time of modified fire water decreases, and still shorter than the discharging time of tap water, but the gap between the two is gradually narrowing. The choice of sprinkler type and nozzle aperture play an important role in discharging modified fire water. The results prove the feasibility of modified fire water using in high speed sprinkler system.