内混式空气雾化喷嘴雾化特性及降尘效率研究

为了掌握内混式空气雾化喷嘴喷雾特性及降尘性能,借助自主研发的喷雾降尘实验平台,对内混式空气雾化喷嘴与X旋流型压力喷嘴流量、雾化角、射程、雾滴体积分数、雾滴粒径、雾滴速度等喷雾特性参数及降尘效率进行了实测,并对实验结果作对比分析。结果表明:随着供水压力的增加,内混式空气雾化喷嘴水流量和气流量分别呈指数形式递增和递减,气液质量流量比不断下降;压力喷嘴水流量随着供水压力的增大而增大,水流量与供水压力的1/2次方成正比。随着供水压力的增加,2种喷嘴的雾化射程、雾滴体积分数及雾滴速度均增大。X旋流型压力喷嘴雾化角明显大于空气雾化喷嘴,其喷雾作用范围更宽;随着供水压力的不断提高,空气雾化喷嘴雾化角呈现先增大后减小的变化规律,而压力喷嘴则一直以较小的幅度不断减小。空气雾化喷嘴由于有压缩空气作为助力,在供水压力较低时能获得较为理想雾滴粒径,且随着供水压力的增大,雾滴粒径不断增大;普通压力喷嘴的雾化粒径随着供水压力的提高而减小,且需在较高的供水压力下才能获得理想的雾滴粒径。在相同的供水压力下,空气雾化喷嘴雾滴粒径和水流量均小于压力喷嘴,而雾滴体积分数、雾滴速度及降尘效率均高于压力喷雾。气水喷雾较压力喷雾具有明显的优势,获得相同的降尘效率,气水喷雾耗水量仅约为压力喷雾的一半。

Spray characteristics and dust removal efficiency of internal-mixing air atomizing nozzle

In order to study the spray characteristics and dust removal properties of internal-mixing air atomizing nozzle,based on the experimental platform designed by authors for spray and dust removal,the dust removal efficiencies and spray performance parameters of the internal-mixing air atomizing nozzle and the X-type swirl pressure nozzle were measured.The spray performance parameters measured in the experiment include flow rate,droplet size,droplet volume concentration,spray angle and droplet velocity.The study results indicate that the water flow rate of air atomizing nozzle appears exponential growth with the increase of water supply pressure,and the air flow rate decreases in the way of exponential.The air-liquid mass flow ration (ALR) decreases with the increase of water supply pressure.For the pressure nozzle,the water flow rate increases with the increase of the water supply pressure,and the water flow rate is proportional to the square root of water pressure.With the increase of water supply pressure,the spray range,droplet volume concentration and droplet velocity of two kinds of nozzle all increase.The atomization angle of swirl pressure nozzle is significantly larger than that of air atomizing nozzle,which has wider coverage.As the water supply pressure increases,the atomization angle of atomizing nozzle increases first and then decreases,and it decreases continuously at a modest pace for the X-type swirl pressure nozzle.With the help of compressed air,the atomizing nozzle can acquire the ideal droplet size under low water pressure,and the droplet size increases with the increase of the water supply pressure.For the pressure nozzle,the droplet size shows a change rule of decreasing with the further increase of the water supply pressure,only when the water pressure is high can reach the appropriate droplet size.Under the same water pressure,the droplet size and water flow rate of air atomizing nozzle are both less than those of pressure nozzle,but the droplet volume concentration,droplet velocity and dust removal efficiency are all higher than those of pressure nozzle.Compared with the pressure spray,the air-water spray has a significant advantage.For the same dust removal efficiency,the water consumption of air-water spray is merely half of those of pressure spray.