论文标题
韧带不稳定性和剪切流中分解的数值分析
Numerical analysis of ligament instability and breakup in shear flow
论文作者
论文摘要
在这项研究中，我们对剪切流中韧带的不稳定性进行了数值分析，并研究了空气剪切对韧带界面的生长速率，分解时间和液滴直角的影响。韧带通过气流的剪切在流动方向上拉伸。此外，随着剪切流的影响增加，韧带变形成液体板，并在液体板的中心形成穿孔。液体板由于穿孔的生长和表面张力的影响而分解，形成两个韧带，直径小于原始韧带的韧带。气流的剪切导致原始韧带的细长，韧带的横截面变成椭圆形，从而增加了不稳定。结果，韧带的生长速率超过了理论值，并且随着初始干扰的波数增加而增加。因此，由于控制韧带破裂的波数增加，剪切流中形成的液滴的直径降低，并且由于生长速率增加，因此韧带的破裂时间减少。随着剪切流的速度差异增加，韧带形式的收缩较早，卫星液滴的直径增加。随着卫星液滴的直径增加，主液滴的直径减小，液滴直径的分散会减小，从而使直径均匀。
In this study, we perform a numerical analysis of the instability of a ligament in shear flow and investigate the effects of air-liquid shear on the growth rate of the ligament interface, breakup time, and droplet diameter formed by the breakup. The ligament is stretched in the flow direction by the shearing of airflow. Furthermore, as the influence of the shear flow increases, the ligament becomes deformed into a liquid sheet, and a perforation forms at the center of the liquid sheet. The liquid sheet breaks up due to the growth of the perforation and contracts under the influence of surface tension, forming two ligaments with diameters smaller than that of the original ligament. The shearing of the airflow causes the original ligament to elongate, and the cross-section of the ligament becomes elliptical, which increases instability. As a result, the growth rate of the ligament exceeds the theoretical value, and increases with increasing wavenumber of the initial disturbance. Therefore, the diameter of the formed droplets in shear flow decreases due to the increase in the wavenumber that governs the breakup of the ligament, and because the growth rate increases, the breakup time for the ligament decreases. As the velocity difference of the shear flow increases, constrictions of the ligament form earlier and the diameter of the satellite droplet increases. As the diameter of the satellite droplet increases and that of the main droplet decreases, the dispersion of the droplet diameter decreases, making the diameter uniform.
