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Published on: February 17, 2019
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Fluid ejections in nature
Elio J Challita1,2, Pankaj Rohilla1, M Saad Bhamla1,2
1School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, 311 Ferst Drive NW, Atlanta, GA, 30332, USA.
Arxiv
|March 18, 2024
Summary
Biological fluid ejections, from fungi to whales, are vital. This review explores their complex physics, governing forces, and engineering applications.
Area of Science:
- Biophysics
- Fluid Dynamics
- Biomechanics
Background:
- Fluidic ejections are a universal biological phenomenon, crucial for functions like excretion, spore dispersal, and prey capture across diverse organisms.
- These ejections range from microscopic fungal spore dispersal to large-scale whale exhalations, involving both active muscle-driven and passive osmotic/gravitational mechanisms.
Approach:
- This review synthesizes the complex fluid physics governing biological ejections across various scales.
- A framework using dimensionless numbers is introduced to classify ejection behaviors, distinguishing between dripping and jetting regimes.
- The study examines both active (muscle-powered) and passive (gravity/osmosis-driven) ejection systems.
Key Points:
- The physics of complex fluids in biological ejections remain understudied.
- Understanding governing forces and transitions (e.g., dripping to jetting) is essential.
- Identifies potential bioinspired engineering applications in soft robotics, additive manufacturing, and drug delivery.
Conclusions:
- This work integrates biomechanics, living systems physics, and fluid dynamics to explain biological ejections.
- It provides a comprehensive overview of the biophysics of fluid ejections, highlighting their diversity and importance.
- The findings open avenues for future bioinspired research and technological innovation.
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