煤矿井下气水喷雾雾化特性实验研究

为了分析煤矿井下气水喷雾雾化特性,基于自行设计的气水喷雾实验平台,采用电磁流量计、空气质量流量计及马尔文实时高速喷雾粒度分析仪对空气雾化喷嘴流量特性、雾化粒度的空间分布规律及影响因素开展了实验研究。结果表明:随着供水压力的增加,喷嘴耗气量以指数形式不断递减,而耗水量以指数形式递增;喷嘴耗气量随供气压力以指数形式递增,而喷嘴耗水量基本呈现线性递减趋势。雾滴粒径沿喷嘴轴线方向不断增大;距离喷嘴较近的纵断面上,雾滴粒径沿径向不断增大,并呈现不对称分布;位于雾流中部的纵断面上,轴线附近区域雾滴粒径沿径向不断增大,而雾流外部区域雾滴粒径呈现沿重力方向增大的趋势;在靠近雾流末端衰减区内,雾滴粒径沿重力方向不断增大。供气压力一定时,雾滴粒径随着供水压力的增加呈现先增大后减小的变化规律,且供气压力越大所对应的拐点水压越高;随着供气压力的增加,雾滴粒径不断减小,且减小幅度随供气压力增加而有所下降。

Atomization characteristics of air-water spray in underground coal mine

In order to study the atomization characteristics of air-water spray in underground coal mine,the electromagnetic flowmeter,air-mass flowmeter and Malvern droplet particle size analyzer were used to make a systematic investigation on the nozzle flow characteristics and the spatial distribution law and influence factors of atomized particle size based on the experimental system designed by authors.The study results indicate that the water consumption of nozzle appears exponential growth with the increase of water supply pressure,and the air consumption decreases in the way of exponential.With the increase of air supply pressure,the air consumption of nozzle increases in the way of exponential,and the water consumption appears linearly decrease.The particle size of droplets increases with the distance away from nozzle in axial direction.On the longitudinal section near the nozzle,the particle size of droplets increases from inside to outside,and the particle size presents an asymmetric distribution.On the longitudinal section located in central spray flow,the particle size of droplets near the central axis increases with the distance away from the axis,and it presents an increase trend along gravity direction in the outer domain of spray flow.In the attenuation zone of the spray flow,the particle size of droplets increases continuously along gravity direction.With the increase of water supply pressure,the particle size of droplets increases first and then declines slightly.The particle size of droplets decreases with the increase of air supply pressure,and the amplitude shows a decrease trend.