二元空气雾化喷嘴研究

本文是从理论及试验二种途径研究二元空气雾化喷嘴内液膜的形成,沿程变化和雾化。 理论分析是有根据地设想一个雾化物理模型,对二元非稳态Navier-Stokes方程进行了求解,并得到液流速度、液层厚度等的关系式,以及分析了液膜雾化条件,并得液滴平均直径关系式。由于篇幅所限,本文仅摘要说明理论分析过程及其所得结果,简要地介绍试验内容,其中包括自制的激光测雾仪测量雾滴直径,脉冲激光显微摄影技术拍摄雾化过程细节,以及电阻法及投影法测量液膜厚度。 试验结果得到液膜沿程厚度的半经验式和各参数对雾滴直径的影响关系,并证明了理论符合试验。

INVESTIGATION ON TWO-DIMENSIONAL AIRBLAST ATOMIZER

Formation,variation and atomization of a liquid layer in a two-dimensional airblast atomizer have been investigated theoretically and experimentally.A physical model of atomization was proposed in the analysis,the unstable N-S equations of the two-dimensional liquid layer were solved,and the expressions for liquid layer thickness h and mean drop diameter Dm have been derived as follows: at lower air velocity and smaller liquid viscosity conditionat higher air velocity conditionand Comprehensive experiments have been done.A pulse laser photomicrography was applied to observing the details of the atomization process of a liquid layer and the pictures taken were quite distinct.A light-scattering technique with laser as light source was used to measure the mean drop diameter D32 The results testified that D32 was proportional to ug-1.7 at lower air velocity and to ug-1 at higher air velocity.A method with a probe measuring electrical resistance of a water layer was employed to determine the thickness of the water layer.The data of experiments were consistent with the theoretical analysis,and the semiempirical equations were yielded as follows:water.Kerosene: