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Published on: February 17, 2019
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Fluid Ejections in Nature
Elio J Challita1,2, Pankaj Rohilla2, M Saad Bhamla2
1George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia, USA.
Annual Review of Chemical and Biomolecular Engineering
|April 26, 2024
Summary
Biological fluid ejections, from fungi to whales, are vital. This review explores their complex physics, governing forces, and bioinspired engineering applications.
Area of Science:
- Biophysics
- Fluid Dynamics
- Biomechanics
Background:
- Fluid ejections are common biological phenomena across diverse organisms, serving critical functions like excretion, defense, and reproduction.
- These ejections range from microscopic fungal spore dispersal to large-scale whale exhalations, involving both active and passive mechanisms.
Purpose of the Study:
- To review the complex fluid physics governing biological ejections across various scales.
- To introduce a framework using dimensionless numbers to understand ejection behaviors and governing forces.
- To highlight the potential for engineering applications inspired by these natural phenomena.
Main Methods:
- Literature review synthesizing research on biological fluid ejections.
- Analysis of fluid dynamics principles applied to biological systems.
- Framework development using dimensionless numbers to classify ejection regimes.
Main Results:
- Identified universal principles governing fluid ejections in biology.
- Delineated transitions between dripping and jetting phenomena using dimensionless parameters.
- Highlighted the understudied area of complex fluid ejections.
Conclusions:
- Biological fluid ejections are governed by intricate fluid physics with broad implications.
- Understanding these phenomena can inspire advancements in soft robotics, additive manufacturing, and drug delivery.
- This review bridges biomechanics and fluid dynamics, offering a foundation for future bioinspired research.
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