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Updated: Sep 13, 2025

Induction of Microstreaming by Nonspherical Bubble Oscillations in an Acoustic Levitation System
Published on: May 9, 2021
Acoustic standing wave driven bubble dynamics in Oldroyd-B fluids using a semi analytical approach.
Shervin Alirahimi1, Hatef Mohammadi Alashti1, Azadeh Jafari2
1School of Mechanical Engineering, College of Engineering, University of Tehran, P.O. Box 11155-4563, Tehran, Iran.
This study investigates bubble oscillation in viscoelastic fluids using a semi-analytical method. Bubble oscillations become chaotic at high Reynolds numbers, while lower numbers maintain periodic behavior.
Area of Science:
- Fluid Dynamics
- Non-Newtonian Fluid Mechanics
- Acoustics
Background:
- Bubble oscillation is crucial in medical and industrial fields.
- Understanding bubble dynamics in viscoelastic fluids is complex.
- Existing models often simplify fluid behavior.
Purpose of the Study:
- To investigate bubble oscillation in a viscoelastic fluid using a semi-analytical approach.
- To analyze the influence of dimensionless parameters on bubble dynamics.
- To determine the conditions leading to chaotic versus periodic bubble oscillations.
Main Methods:
- Utilized the Rayleigh-Plesset equation for bubble dynamics.
- Incorporated the Oldroyd-B constitutive equation for viscoelastic fluid behavior.
- Transformed the governing equation into a system of ODEs solvable numerically.
Main Results:
- Dimensionless parameters significantly influence bubble oscillation amplitude.
- Increased Reynolds number, acoustic pressure, and frequency enhance oscillation amplitude.
- Chaotic oscillations emerge around a Reynolds number of 1.1; periodic oscillations occur at lower values.
- A Deborah number of 2.4 was the highest observed for bubble oscillations.
- Elastic effects plateau in impact on oscillations beyond an elasticity number of 10.
Conclusions:
- The study provides insights into bubble dynamics in viscoelastic media.
- Reynolds number is a key determinant of oscillation behavior (chaotic vs. periodic).
- Fluid elasticity, quantified by Deborah and elasticity numbers, plays a critical role up to a certain threshold.
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