液体环轴对称抛洒首次破碎的理论分析

An investigation of the primary breakup in the axisymmetric dissemination of a liquid ring

对于水和无水乙醇环形轴对称抛洒实验的首次破碎结果的分析表明,在给定实验条件下,液体密度大约是气体的1000倍,液体首次破碎的过程分2个阶段:首先,界面不稳定性非线性发展,液体尖钉在惯性力和空气阻力的作用下,拉伸变细变长;然后在射流不稳定性的作用下,断裂成液体珠串。这个理论分析给出的首次破碎的平均液体直径与实验结果基本一致。理论分析表明,无水乙醇破碎液滴的平均直径比水液滴小,是无水乙醇表面张力值仅为水的1/3的一个必然结果。

Some instability analyses were carried out according to the experimental results of primary breakup of symmetrical spray of water and anhydrous-ethanol. It is shown that the process of primary breakup can be divided into two stages in the experimental condition： the first stage is the nonlinear development of liquid instability and the stretch of spike to form a iet caused by inertia force and resistance force of air; the second stage is the process of breakup to liquid bead cluster caused by jet instability. The analyzed result of droplet average diameter of primary breakup is approximate to the experimental result. According to the analyses, it is a necessity that the droplet average diameter of anhydrous-ethanol is smaller than one of water because the surface tension of anhydrous-ethanol is only one-third of the counterpart of water.