https://scholars.lib.ntu.edu.tw/handle/123456789/348323
標題: | Binary droplet collision at high Weber number | 作者: | Pan, K.-L. Chou, P.-C. Tseng, Y.-J. KUO-LONG PAN |
公開日期: | 2009 | 卷: | 80 | 期: | 3 | 來源出版物: | Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | 摘要: | By using the techniques developed for generating high-speed droplets, we have systematically investigated binary droplet collision when the Weber number (We) was increased from the range usually tested in previous studies on the order of 10 to a much larger value of about 5100 for water (a droplet at 23 m/s with a diameter of 0.7 mm). Various liquids were also used to explore the effects of viscosity and surface tension. Specifically, beyond the well-known regimes at moderate We's, which exhibited coalescence, separation, and separation followed by satellite droplets, we found different behaviors showing a fingering lamella, separation after fingering, breakup of outer fingers, and prompt splattering into multiple secondary droplets as We was increased. The critical Weber numbers that mark the boundaries between these impact regimes are identified. The specific impact behaviors, such as fingering and prompt splattering or splashing, share essential similarity with those also observed in droplet-surface impacts, whereas substantial variations in the transition boundaries may result from the disparity of the boundary conditions at impacts. To compare the outcomes of both types of collisions, a simple model based on energy conservation was carried out to predict the maximum diameter of an expanding liquid disk for a binary droplet collision. The results oppose the dominance of viscous drag, as proposed by previous studies, as the main deceleration force to effect a Rayleigh-Taylor instability and ensuing periphery fingers, which may further lead to the formations of satellite droplets. © 2009 The American Physical Society. |
URI: | http://www.scopus.com/inward/record.url?eid=2-s2.0-70349510893&partnerID=MN8TOARS http://scholars.lib.ntu.edu.tw/handle/123456789/348323 |
DOI: | 10.1103/PhysRevE.80.036301 | SDG/關鍵字: | Binary droplet collisions; High-speed; Impact behavior; Rayleigh-Taylor instabilities; Satellite droplets; Secondary droplets; Simple model; Substantial variations; TO effect; Transition boundaries; Viscous drag; Weber numbers; Coalescence; Drop formation; Energy conservation; Separation; Surface tension; Drop breakup |
顯示於: | 機械工程學系 |
在 IR 系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。