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Thomson-Einstein's Tea Leaf Paradox Revisited: Aggregation in Rings
Kirill Kolesnik1, Daniel Quang Le Pham1, Jessica Fong1
1Department of Biomedical Engineering, University of Melbourne, Melbourne, VIC 3010, Australia.
Micromachines
|November 25, 2023
Summary
Particle inertia in rotating fluids creates a focusing spot, defying expectations. This study reveals vessel shape and rotation speed influence particle aggregation, forming both central spots and stable rings.
Area of Science:
- Fluid Dynamics
- Particle Physics
Background:
- Particle inertia in rotating fluids typically prevents central focusing.
- Secondary flow with radial components drives particle aggregation, known as Thomson-Einstein's tea leaf paradox.
Purpose of the Study:
- To investigate particle aggregation dynamics in rotating fluids.
- To explore the influence of rotational velocity and vessel shape on particle focusing.
Main Methods:
- Combined experimental and computational approach.
- Analysis of particle aggregation in rotating fluid systems.
Main Results:
- Confirmed the formation of a single particle focusing spot in the vessel center.
- Demonstrated repeatable formation of stable ring-shaped particle arrangements.
- Identified significant influence of rotational velocity and vessel shape on particle equilibrium positions.
Conclusions:
- Particle aggregation in rotating fluids is complex, influenced by factors beyond inertia.
- Vessel geometry plays a crucial role in determining particle arrangement patterns.
- The study expands understanding of the Thomson-Einstein's tea leaf paradox by identifying novel aggregation patterns.
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