Files in this item
Files | Description | Format |
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image/jpeg ![]() | Image | JPEG image |
Description
Title: | The Ephemeral Jelly |
Author(s): | Hoque, Muhammad Jahidul |
Contributor(s): | Yan, Xiao; Miljkovic, Nenad |
Subject(s): | Mechanical Science and Engineering |
Abstract: | Though this jet-like internal flow pattern inside of a water droplet resembles a mushroom, it swims like a jellyfish. This microscopic phenomenon was observed when two micro-droplets coalesce. Internal droplet flow has remained a challenge to visualize for over a century due to the small length and time scales associated with the flows. In order to study droplet coalescence dynamics, we developed a droplet dispensing and visualization system. To track the internal flow front, and ethanol (20 wt%) water mixture was used as the working fluid. Due to the unequal evaporation rates between water and ethanol, a density gradient is developed at the liquid-gas interface of the droplets, resulting in a lower refractive index at the interface compared to that in the bulk liquid. Jet-like internal flow and vortex rings create a jellyfish-like structure inside the merging droplet. The chronophotograph demonstrates the previously unidentified jet-like flow that occurs during the coalescence of droplets having different sizes. |
Issue Date: | 2020 |
Type: | Text Image |
URI: | http://hdl.handle.net/2142/106803 |
Rights Information: | Copyright 2020 Muhammad Jahidul Hoque |
Date Available in IDEALS: | 2020-04-14 |