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Updated: May 24, 2026
10:03
Uncoupling Coriolis Force and Rotating Buoyancy Effects on Full-Field Heat Transfer Properties of a Rotating Channel
Published on: October 5, 2018
Two-fluid confined flow in a cylinder driven by a rotating end wall
P T Brady1, M Herrmann, J M Lopez
1School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287, USA.
Summary
Numerical simulations reveal that vortex bending, not stretching, dominates fluid dynamics in rotating immiscible fluids. Surface tension significantly impacts interfacial deformation, making zero surface tension an invalid approximation.
Area of Science:
- Fluid Dynamics
- Computational Physics
Background:
- Studying the behavior of immiscible fluids in rotating systems is crucial for understanding various industrial and geophysical processes.
- Previous research often simplified fluid interfaces or neglected the interplay of forces like viscosity, surface tension, and inertia.
Purpose of the Study:
- To numerically investigate the flow dynamics of two immiscible fluids in a rotating cylinder.
- To analyze the influence of parameters such as rotation rate, viscosity ratio, surface tension, and gravity on the fluid interface and flow structure.
Main Methods:
- Numerical simulations of two-phase flow in a cylinder driven by bottom wall rotation.
- Parameter variation to isolate effects of inertia, surface tension, and gravity.
- Analysis of vortex dynamics (bending vs. stretching) and interfacial layer formation.
Main Results:
- Flow dynamics are dominated by vortex bending, even with significant interfacial deformation.
- The viscosity ratio critically influences interfacial layer structure and upper fluid equilibration.
- Surface tension effects are significant, reducing interfacial deformation; zero surface tension is not a valid simplification.
Conclusions:
- Vortex bending is the primary mechanism governing the flow, overriding vortex stretching in this regime.
- Interfacial layer dynamics, driven by vortex bending, dictate the upper fluid's flow.
- Accurate modeling of immiscible fluid flow requires considering significant surface tension effects.
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