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Preparation of Free-Surface Hyperbolic Water Vortices
Published on: July 28, 2023
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Drag of buoyant vortex rings.
Ahmadreza Vasel-Be-Hagh1, Rupp Carriveau1, David S-K Ting1
1Turbulence and Energy Laboratory, Lumley Centre for Engineering Innovation, University of Windsor, Ontario N9B 3P4, Canada.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|November 14, 2015
Summary
This study modifies Turner
Area of Science:
- Fluid dynamics
- Vortex ring dynamics
Background:
- Buoyant vortex rings are a common phenomenon in fluid mechanics.
- Turner's radius model describes the growth of vortex rings but neglects viscous effects.
- Understanding viscous effects is crucial for accurate vortex ring modeling.
Purpose of the Study:
- To modify Turner's radius by incorporating viscous effects.
- To develop a model that accounts for both buoyancy and viscosity in vortex ring dynamics.
- To determine the drag coefficient of buoyant vortex rings.
Main Methods:
- A perturbation analysis was performed on an existing model.
- The analysis introduced a first-order perturbation correction for viscosity.
- Photographically measured radii were used to fit the modified equation.
Main Results:
- A modified radius equation was derived, including buoyancy and viscous terms.
- The model yields the time history of the drag coefficient for buoyant vortex rings.
- The drag coefficient was calculated for a vortex ring at a Bond number of approximately 85.
Conclusions:
- The proposed model successfully incorporates viscous effects into Turner's radius.
- The method allows for the determination of the drag coefficient of buoyant vortex rings.
- This approach is applicable to vortex rings at various Bond numbers.
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