Abstract: The influence of viscoelasticity on primary atomization of syrup and syrup polymer solutions was studied experimentally with the coaxial air-blast atomizer.The breakup regimes were divided according to high-speed camera graphs and breakup instability characteristics on the surface of liquid jet were performed.The results proved that primary breakup of the experimental medium could be divided into three regimes, non-axisymmetric oscillation, membrane breakup and fiber breakup.However, the breakup transition Weber number of syrup-polymer was larger than that of syrup solution with the same viscosity.The instability wavelength on the surface of liquid was closely related to air velocity and liquid viscoelasticity, the elasticity parameter Wi was introduced in the instability wavelength theory model that considered the influence of vorticity-layer, and a new equation of instability wavelength was fitted with relevant characteristic parameters.

Key words: viscoelasticity, air-blast atomization, breakup regimes, instability wavelength

摘要： 以糖浆溶液和糖浆聚合物溶液为液相介质、空气为气相介质,采用同轴双通道气流式雾化喷嘴研究黏弹性对液体初次雾化特性的影响,根据高速摄像拍摄的图片对雾化模式进行研究,并重点探讨了液柱表面的不稳定特性。研究结果表明,两种液相介质的初次雾化可分为非轴对称振荡模式、膜破裂模式和拉丝破裂模式,糖浆聚合物溶液各个破裂模式的边界Weber数大于同等黏度的糖浆溶液。液体表面的不稳定波长与气速及液体自身的黏弹性密切相关,在考虑边界层影响的不稳定波长理论模型的基础上引入弹性参数Wi,并通过数据拟合得到新的不稳定波长关系式。

关键词: 黏弹性, 气流式雾化, 破裂模式, 不稳定波长