新型预混式气动喷嘴结构设计及其工作原理

摘要

A new type of premixed pneumatic nozzle was designed based on the crushing theory, in which, the gas flows into the vortex chamber from the tangential flow channel and the liquid to be broken flows into from the center pipe at the top of the nozzle.Having CFD technology adopted to simulate both velocity distri-bution and ejection effect of the nozzle structure of ladder type without expansion section and laval type was im-plemented to indicate that the nozzle of laval type is the best in the structure.Comparing the the ejection effect of the laval nozzle with four and double channels respectively shows that,the laval nozzle with multi flow chan-nels has poor vortex effect.Through analyzing the interaction of the rotational gas and the liquid in the center and the deceleration and supercharging of the expansion section,the operating principle of the double-channel laval nozzle was further explored.%基于破碎理论设计了一种新型预混式气动喷嘴,气体作为旋流流体从切向流道通入旋流室,而待破碎液体则从喷嘴顶部中心管通入.首先采用CFD技术模拟了阶梯型、无扩张段和拉瓦尔型喷嘴的速度分布情况和喷射效果,确定最佳结构为拉瓦尔型.然后对四流道和双流道拉瓦尔型喷嘴的喷射效果进行了比较,发现流道多反而影响旋流效果.最后通过旋流气体与中心流入液体的相互影响和扩张段的减速增压作用进一步探索了双流道拉瓦尔型喷嘴的工作原理.