Development Of Detection System On Explosion Suppression Performance Of Ultrafine Powder

Active explosion suppression with early explosion signal active monitor which take water mist\inert gas, ultrafine activated powder as suppressant is becoming research hotspot. Ultrafine powder have attracted much attention because it had physical and chemical explosion suppression function, long residence time in the air and the advantage of interacting with explosive flame easily. Therefore, the paper aims to study explosion suppression performance of ultrafine powder in laminar flames states. A set of experimental system is designed, including explosion vessels, gas distribution system, ignition facility, explosion measurement system\acquisition and control system and the flow field observation system. Contrast experiment was conducted between Methane laminar premixed flame propagation, Ultrafine ABC dry powder and silica powder explosion suppression performance under the experimental system. Microscopic study on explosion suppression powder and explosion flame interaction is an important supplement to formerly study methods. Specific work points are divided into following three points:(1) Long square pipe explosion vessel(size:120mm×120mm×600mm) was designed, equipped with glass observation window, ion probe, superfine thermocouple and pressure sensor. High voltage ignition method and air distribution spray method comprise initial experimental conditions. A set of acquisition and controlling system was developed based on PCI2006 acquisition card.(2) A set of flow field observation system was composed of high-speed cameras and schlieren apparatus, analyzing the parameters between light path of schlieren apparatus, object plane selection and blade set, high-speed cameras and schlieren apparatus, calculating flame propagation velocity by using image processing method.(3) System feasibility was debugged and verified by methane flame propagation blank experiment. Taking the experimental result of schlieren record image, flame propagation velocity as the basis for analysis, a contrast experiment was designed between ultrafine ABC dry powder and silicon dioxide. The experiment found that explosion suppression performance of ultrafine ABC dry powder is far better than silicon dioxide. A certain amount of ultrafine ABC dry powder and silicon dioxide can effectively reduce the temperature of the flame front, intensity of combustion reaction, flame propagation velocity and the growth rate of the pressure in the pipeline, but accelerating flame propagation velocity exists in silicon dioxide, flame appears honeycomb shape because two powders were added.