Spray impact: Rim transverse instability initiating fingering and splash, and description of a secondary spray
Spray impact: Rim transverse instability initiating fingering and splash, and description of a secondary spray
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DOI：
10.1063/1.2364187
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发表时间：
2006-10-01
影响因子：
4.6
通讯作者：
Tropea, Cam
中科院分区：
文献类型：
--
作者：
Roisman, Ilia V.;Horvat, Kristijan;Tropea, Cam
在本文中，考虑了正常喷雾对刚性壁的冲击，导致二次喷雾的形成。飞溅的机制可以通过限制自由液层的边缘的弯曲不稳定性来解释。轮缘的线性稳定性分析是在长波准一维方法的框架中进行的。边缘不稳定是由与进入边缘的液体的惯性相关的力矩引起的。接下来，使用相位多普勒仪器测量液滴速度的两个分量及其直径，以及各种通量密度矢量（数量、体积、质量通量）和张量（动量通量）。结果表明，液滴撞击的粘性长度尺度可以用来描述飞溅阈值、二次液滴的直径及其速度。因此，提出了二次喷雾的封闭半经验模型，并使用基于欧拉-拉格朗日方法的喷雾传输数值模拟进行了验证。 (c) 2006 年美国物理研究所。
In this paper, normal spray impact onto a rigid wall, leading to the formation of secondary spray, is considered. The mechanism of splash is explained by the bending instability of a rim bounding a free liquid sheet. The linear stability analysis of the rim is performed in the framework of the long-wave, quasi-one-dimensional approach. The rim instability is caused by the moment of forces associated with the inertia of the liquid entering the rim. Next, two components of the drop velocity and their diameter, as well as various flux density vectors (number, volume, mass fluxes) and tensors (momentum flux), are measured using a phase Doppler instrument. It is shown that the viscous length scale of drop impact can be used in describing the splash threshold, diameter of secondary droplets, and their velocity. Consequently, a closed semi-empirical model for the secondary spray has been proposed and validated using a numerical simulation of spray transport based on an Euler-Lagrange approach. (c) 2006 American Institute of Physics.