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Published on: September 5, 2017
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Plume-scale confinement on thermal convection.
Daisuke Noto1, Juvenal A Letelier2, Hugo N Ulloa1
1Department of Earth and Environmental Science, University of Pennsylvania, Philadelphia, PA 19104.
Summary
A new metric, the degree of confinement, unifies the study of thermal convection across diverse systems. It characterizes transitions between free and confined flow regimes, offering a plume-centric view of heat transport and mixing.
Area of Science:
- Fluid dynamics
- Heat transfer
- Geophysics
Background:
- Thermal convection is ubiquitous in natural and engineered systems.
- A unified framework for characterizing transitions between free and confined convection is lacking.
- Convection is crucial for energy transport and mixing in diverse environments.
Purpose of the Study:
- To develop a unified formulation for thermal convection regimes.
- To investigate the impact of system geometry on convective transitions.
- To understand the mechanisms controlling geometrically controlled convection.
Main Methods:
- Laboratory experiments using Hele-Shaw geometries.
- Analysis of flow structures and heat transport scaling.
- Introduction and application of the degree of confinement metric.
Main Results:
- Identified multiple transitions in flow structures and heat transport.
- Characterized four distinct convective regimes (flow dimensionality and time dependency).
- Demonstrated that transitions correlate with the degree of confinement.
Conclusions:
- The degree of confinement provides a universal metric for characterizing convection.
- This metric unifies the understanding of convection from a plume's perspective.
- The findings advance the study of heat and mass transfer in confined systems.
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