Droplet Impact Research
High speed videos of viscous liquid droplets impacting viscous liquid pools.
At Northeastern University, I had the opportunity to work in Professor Xiaoyu Tang's lab where we studied liquid droplet impact mechanics. While droplet impact on a solid substrate is well understood, the behavior on a liquid substrate is vastly different. My research involved capturing high-speed videos of various liquid droplets impacting pools of other liquids, while systematically varying different parameters such as viscosity and Weber number to evaluate the impact behavior.
Understanding the different behavior shown can have both beneficial and detrimental effects on various applications.
To conduct our experiments, I designed our experimental setup which utilizes two high-speed Phantom cameras (one color and one monochrome) and an aluminum extrusion fixture. Droplets are generated using a syringe pump and fall into pools of liquid contained in custom-made square glass reservoirs. By attaching the 8020 fixture to the optical table, we can modify the impact speed by changing the relative distance between the syringe tip and the reservoir surface.
Highspeed video camera pointed at fluid resevior atop linear stage
Experimental setup and parameters for droplet on oil layer experiments
Our recent research has focused on the effects of viscosity and impact velocity on the merging of liquid droplets into pools/layers of different liquids. In the future, we plan to investigate the impact and reaction of liquid alginate droplets with a liquid pool to evaluate the complex geometries created.
Oil layer experiment regime map (see above video for behavior classification)
By determining the parameters that dictate which behavior occurs, we can enable engineers to design with certain droplet behavior in mind. Our goal is to create regime maps that detail the impact behavior and validate our findings through thorough analyses of the impact energy exchange.
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To ensure an unbiased and consistent analysis of the video data, we use a Matlab script that leverages the image processing toolbox to extract relevant parameters. Going forward, I will be working on modifying and expanding this script to accommodate new research needs and to improve the efficiency of the video processing pipeline.
This research has a wide variety of applications including but not limited to:
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Improving the efficiency of fuel combustion in engines
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Increasing the quality of industrial spray painting and inkjet printing
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Mitigating the spread of viruses through respiratory droplets
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Understanding the specifics of pollution spread through precipitation
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While our research has been focused on viscous layers and alginate reactions, with the designed experimental setup and analysis tools, an unlimited number of droplet impact phenomena can be investigated.
Here is a poster we created for presentation at Northeastern SOURCE 2021:
