气泡喷嘴下游雾化与流场特性的研究

本文用激光粒子动态分析仪（ＰＤＡ）测量了水平喷射的气泡雾化喷嘴下游不同截面上的雾化液滴平均直径和速度分布，用水在常温，常压下进行试验，液体的喷射压力变化范围为１５０～５５０ｋＰａ；气液比的变化范围为０～０．１２。研究了随着喷射距离的增大，气泡喷嘴的雾化与流场特性的变化规律，试验结果表明，沿着喷射方向，与喷孔一定距离内，气泡喷嘴的液雾存在明显的扩散过程，气泡喷嘴的喷雾速度呈典型的抛物状分布，在喷雾轴

Influence of Downstream Distance on Spray Characteristics of Effervescent Atomizers

The atomization and flow field performance of an effervescent atomizer has been investigated.Variations of mean drop size,drop-size distribution and velocity characteristics on different traverse sections of the spray are obtained using the Particle Dynamics Analyzer (PDA).The liquid employed is water and all tests are carried out at normal atmospheric pressure and temperature.Water injecting pressures are varied from 150kpa to 550kpa,and air/liquid ratios from 0 to 0.12by mass.Investigations are focused on the effect of downstream distance on atomization and flow field quality of the effervescent atomizer.The results illustrate that obvious spray dispersion exists within certain downstream distance of the atomizer.Drop velocity data have shown a typical parabolic-shaped distribution with the maximum value at the axis of the spray.The Rosin-Rammler parameter q,which represents the drop-size distributions of the spray produced in effervescent atomization,are found to be limited from 3.5 to 5.0 at different traverse points on certain testing section from the PDA measurements.