Design Of Vehicle Mounted Gas Driven Dry Powder Fire Extinguishing Device

In recent years, with the widespread of the car, fire from the car cabin is also increasing, therefore, the study of automobile fire extinguishing equipment for engine room is concerned by people. Most of the fires occur in running car, thus this article provides design ideas about fire extinguishing apparatus which can detect the fire automatically and can put out it quickly. This paper presents a fine dry powder fire extinguishing system driven by gas generating agent, then processed it into a prototype,and using the prototype conducts spray experiment, it can optimize the dusting rate by analyzing the data. The main contents are as follows:(1)According to research of the literature and the reference of powder extinguishing apparatus in the market, this paper tries to design a gas generating agent-driven dry powder extinguishing apparatus which includes a gas generator, dry powder tank and nozzle. Firstly, by studying the thruster references and refer to the ballistics theory, it can calculate the volume of the gas generator. Secondly, select the ultrafine extinguishing powder whose extinguishing efficiency is 8 to10 times of the ordinary one, and use the relationship of ultra-fine powder bulk density and the amount of it to calculate the volume size of dry powder tank. Thirdly, for the nozzle,it can refer to recommended test data by British Standards, that is in order to make the dry power in certain diameter pipe not settle down, there is the minimum rate of it, from the relation,it can know the size of the nozzle,and at the same time have the gas generator strength check.(2)Select 5-aminotetrazole, strontium nitrate, manganese dioxide, phenol resin as the recipe of the gas generating agent. According to the principles of the gas generating formulations, the quality of the four agents of this ratio set at 36: 49.5: 10: 4.5. In order to reduce the gas production rate of the gas generating agent, it can be compressed into the column after granulating the raw material, this is the preparation for the experiment.(3)There are four factors influence the dusting rate of the powder extinguishing apparatus, namely dose of gas generating agent, charge coefficient of the dry powder, the size of orifice diameter, the thickness of sealed aluminum foil. According to measuring of the P-t curve in the dry power tank, to analysis the effects of these four factors on the dusting rate.(4)Using Orthogonal experiment to calculate the influence of four factors and determine the significance of the four factors on dusting rate, then to identify factors of the optimal combination of dusting rate by analysis of variance and select a group of assembly program of the highest dusting rate in the orthogonal experiment table to conduct experiment in different angle, which can provide evidence of the installment of the dry powder fire extinguishing equipment in the cabin of the car.