Library Subscription: Guest
Home Archives Officers Future meetings American Society of Thermal and Fluids Engineering
3rd Thermal and Fluids Engineering Conference (TFEC)

ISSN: 2379-1748

WATER-IN-AIR DROPLET GENERATION IN A T-JUNCTION GEOMETRY

M. Mastiani
Department of Ocean and Mechanical Engineering, Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33431, USA

S. Seo
Florida Atlantic University, Boca Raton, FL 33431, USA

Myeongsub (Mike) Kim
Florida Atlantic University, Boca Raton, FL 33431, USA

DOI: 10.1615/TFEC2018.emp.021433
pages 609-620


KEY WORDS: Droplet Micro?uidics , High inertia, Flow regime, T-junction geometry

Abstract

Aqueous microdroplet generation in gaseous phase is an emerging area of research due to its numerous advantages compared to conventional liquid-liquid system including high system throughput and fast mixing. In this paper, we numerically studied the aqueous droplet generation in an inertial air flow in a T-junction droplet generator to understand the droplet formation mechanisms. The Volume of Fluid method is employed to track the interface between two immiscible fluids. The two-phase flow behavior of water droplet in air in the T-junction microchannel over a wide range of Capillary number (0.0001-0.1), and Reynolds number (0.1-100) was examined. At various Reynolds and Capillary numbers, unique flow regime mapping was determined including squeezing, dripping, jetting, unstable dripping, and unstable jetting. It was found that stable aqueous droplets are generated in the squeezing and dripping flow regimes. On the other hand, the unstable dripping flow regime is unable to sustain spherical droplets as they travel downstream. In the unstable jetting flow regime, a stream of water moves downstream and then it's tip splits into small or large fragments of water. The results show that the droplet size increases as Capillary and Reynolds numbers increases and decreases, respectively. As both Capillary and Reynolds numbers increase, the droplet generation frequency increases, reaching its maximum at 223 Hz.

Purchase $20.00 Check subscription Publication Ethics and Malpractice Recommend to my Librarian Bookmark this Page