Radiation dominated acoustophoresis driven by surface acoustic waves

Area of Science:

• Microfluidics
• Acoustic manipulation
• Surface Acoustic Waves (SAWs)

Background:

• Acoustophoresis is a key technique in microfluidics for particle manipulation.
• Experimental studies are abundant, but numerical simulations of SAW-driven acoustophoresis remain underexplored.

Purpose of the Study:

• To develop and validate a numerical model for simulating acoustophoresis driven by surface acoustic waves (SAWs).
• To investigate particle manipulation and focusing phenomena in microfluidic devices utilizing SAWs.

Main Methods:

• Developed a numerical model incorporating acoustic-piezoelectric interactions to simulate SAW generation and acoustic pressure fields.
• Employed acoustic radiation-dominated particle tracing to simulate acoustophoresis for various particle sizes.
• Fabricated a microfluidic device with interdigital transducers (IDTs) for experimental validation.

Main Results:

• Numerical simulations accurately captured particle focusing to pressure nodes, consistent with experimental observations.
• Quantitative agreement was achieved between simulated and experimental particle trajectories by fitting applied voltage.
• Demonstrated particle switching, highlighting the potential for active particle sorting.

Conclusions:

• The developed numerical model effectively simulates SAW-driven acoustophoresis in microfluidics.
• The findings validate the use of numerical simulations for predicting particle behavior in SAW-based microfluidic devices.
• The study paves the way for designing advanced active particle sorting devices using acoustophoresis.