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Updated: Aug 11, 2026
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Fabrication, Operation and Flow Visualization in Surface-acoustic-wave-driven Acoustic-counterflow Microfluidics
Published on: August 27, 2013
Modelling of particle paths passing through an ultrasonic standing wave
R J Townsend1, M Hill, N R Harris
1School of Engineering Sciences, Electromechanical Research Group, University of Southampton, Southampton SO17 1BJ, UK.
Ultrasonics
|March 30, 2004
Summary
Acoustic radiation forces in ultrasonic standing waves enable particle manipulation. A new model optimizes fluid flow and acoustic forces for efficient particle separation in microfluidic devices.
Area of Science:
- Acoustic manipulation
- Microfluidics
- Particle dynamics
Background:
- Ultrasonic standing waves induce acoustic radiation forces, causing particle agglomeration at nodal planes.
- Controlling particle agglomeration requires balancing acoustic and fluid forces, especially in flow-through systems.
Purpose of the Study:
- To develop and validate a particle model for analyzing acoustic and fluid forces in microfluidic separators.
- To optimize particle separation efficiency by investigating acoustic and fluid dynamics.
Main Methods:
- A particle model was developed, integrating computational fluid dynamics (CFD) for fluid drag forces and MATLAB for numerical simulations.
- Particle paths and concentration distributions were calculated based on force components and velocity profiles.
Main Results:
- The model successfully analyzed a microfluidic flow-through separator, predicting particle convergence and separation into high and low concentration outlets.
- Analysis over a frequency range identified resonant frequencies and their impact on separation performance.
Conclusions:
- The developed model accurately predicts particle behavior and separation in microfluidic devices.
- This approach aids in optimizing device design and operational parameters for enhanced particle separation.
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