摘要：为了提高喷嘴的雾化效果, 将超声理论应用到液体射流雾化中, 建立超声雾化喷嘴内部流场特性的数值模型, 并运用流体仿真软件CFD模拟不同射流压力下喷嘴内部速度场的分布情况。数值计算结果表明:超声波明显增强了喷嘴内部速度分布, 增强了湍流效果, 进而提高了液体的雾化能力。沿着喷嘴内部轴线方向, 速度呈先增大后减小的抛物线变化趋势;随着液滴射流压力的增加, 内部速度和湍流效果得到加强, 这为超声雾化喷嘴的设计提供了良好的理论基础。通过比较其它类型的喷嘴, 超声喷嘴的雾化效率明显增强了很多, 这说明超声波应用于喷嘴雾化领域是可行的。

关键词：超声喷嘴；雾化特性；速度分布

Abstract：In order to improve the effect of spray nozzle, the ultrasonic theory was applied to the liquid jet atomization, the numerical model of internal flow field characteristics of ultrasonic atomization nozzle were established, and the different nozzle jet pressure inside the distribution of velocity field were simulated by fluid simulation software CFD. The numerical calculation results show that the ultrasonic velocity distribution obviously enhances the nozzl turbulence effect, thus improves the atomization of liquid. Along the axis of the nozzle inside, the parabolic trend of speed show increases firstly and then decreases. With the increase of droplet jet pressure, the internal velocity and turbulence effect is strengthened. The ultrasonic atomization nozzle design provides a good theoretical basis. By comparing to other types of nozzle, ultrasonic atomizing spray nozzle efficiency significantly increased, it shows that ultrasonic is applied to nozzle area is feasible.

Keywords: ultrasonic nozzle；atomization characteristics；velocity distribution