X形旋流压力喷嘴质量中值直径预测模型

Prediction model of mass median diameter of X-type swirl pressure nozzle

X形旋流压力喷嘴是喷雾降尘常用的一类喷嘴,喷嘴雾滴粒径是重要参数。为了更好地指导喷雾降尘过程中喷嘴的选型,对工业现场常用的6种X形旋流压力喷嘴展开了雾化参数试验研究。通过试验获得了喷嘴水流量、雾化角和喷嘴MMD实测数据,结果表明,X形旋流压力喷嘴MMD随供水压力增大而减小,随喷嘴出口直径增大而增大。在此基础上,根据已有的压力喷嘴MMD经验公式,采用多元非线性回归的方法,建立了X形旋流压力喷嘴MMD预测模型。经试验验证,模型预测值与试验值变化规律一致且平均相对误差仅约7%。所建立的预测模型可用于该类喷嘴MMD的理论预测,指导喷雾降尘工程应用中喷嘴的选型。

X-type swirl pressure nozzle is a type of nozzle commonly used for spray dust reduction,and the nozzle droplet size is an important parameter.To better guide the selection of nozzles in the process of spraying and dust reduction,six types of Xtype swirl pressure nozzles commonly used in industrial fields were tested and studied on atomization parameters.The atomization parameters involved include nozzle water flow,atomization angle,and MMD.Electromagnetic flowmeter and high-performance camera,and Malvern particle size analyzer were used to obtain nozzle atomization parameters.The measured data of six types of X-type swirl pressure nozzle water flow,atomization angle,and nozzle MMD were obtained through a self-designed experimental platform.The results show that with the gradual increase of water supply pressure,the nozzle water flow rate increases,while the atomization angle and MMD show a gradual decrease.The nozzle water flow rate,atomization angle,and MMD decrease with increasing the nozzle outlet diameter.The nozzle flow coefficient decreases with the gradual increase of the nozzle outlet diameter.On this basis,the fitting analysis method is used to obtain the nozzle atomization angle and flow coefficient calculation formula.Combining the atomization angle,flow coefficient calculation formula,and the existing pressure nozzle MMD empirical formula,the method of multiple nonlinear regression is adopted to establish the MMD prediction model of the X-type swirl pressure nozzle.The experimental verification shows that the predicted value of the nozzle MMD prediction model established in this study is consistent with the experimental value and the average relative error is only about 7%.The established prediction model can be used for the theoretical prediction of this type of nozzle MMD,and guide the nozzle selection in the application of spray dust reduction engineering.