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Updated: May 11, 2026
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Published on: May 9, 2021
Interaction of equal-size bubbles in shear flow
Jai Prakash1, Olga M Lavrenteva, Leonid Byk
1Department of Chemical Engineering Technion-Israel Institute of Technology, Haifa 32000, Israel. ceranjp@techunix.technion.ac.il
Summary
Inertial forces cause identical bubbles in shear flow to separate, forming ordered strings. Experiments confirm this theoretical prediction for bubble dynamics in viscous fluids.
Area of Science:
- Fluid dynamics
- Multiphase flow
- Rheology
Background:
- Understanding bubble interactions in shear flow is crucial for industrial processes.
- Previous models often simplified bubble dynamics, neglecting inertial effects at finite Reynolds numbers.
Purpose of the Study:
- To calculate inertia-induced forces between two identical spherical bubbles in a simple shear flow.
- To model the dynamics of injected air bubbles in a sheared viscous fluid within a Couette device.
- To investigate bubble ordering in Taylor vortices.
Main Methods:
- Utilized the reciprocal theorem to calculate inertia-induced forces.
- Employed a theoretical model incorporating bubble interaction forces.
- Conducted experimental observations of bubble dynamics in a sheared viscous fluid.
Main Results:
- Inertial interactions drive bubbles apart over time.
- Equal-sized bubbles form ordered strings with uniform separation.
- Theoretical predictions align well with experimental observations.
Conclusions:
- Inertial forces play a significant role in bubble ordering in shear flows.
- The developed model accurately predicts bubble dynamics and string formation.
- Experimental validation supports the theoretical framework for bubble-fluid interactions.
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