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06:51
Microparticle Manipulation by Standing Surface Acoustic Waves with Dual-frequency Excitations
Published on: August 21, 2018
Acoustic particle velocity horns.
Dimitri M Donskoy1, Benjamin A Cray
1Stevens Institute of Technology, Hoboken, New Jersey 07030, USA. ddonskoy@stevens.edu
The Journal of the Acoustical Society of America
|May 8, 2012
Summary
Acoustic velocity horns (AVHs) amplify particle velocity for vector sensing, unlike pressure horns. These compact, open-ended devices offer directional amplification, with performance controlled by length, throat radius, and flare rate.
Area of Science:
- Acoustics
- Signal Processing
- Transducer Design
Background:
- Conventional acoustic horns amplify pressure, limiting their use in vector sensing.
- Particle velocity amplification is crucial for advanced acoustic applications like vector sensing.
Purpose of the Study:
- To investigate acoustic velocity horns (AVHs) for particle velocity amplification.
- To explore AVH suitability for vector sensing applications.
- To analyze AVH performance independent of overall size relative to acoustic wavelength.
Main Methods:
- Derivation and analysis of Webster's one-dimensional horn equation for AVHs.
- Modeling of single conical, exponential, and double-horn configurations.
- Numerical verification of predicted horn amplification factors.
Main Results:
- AVHs provide significant velocity amplification in a compact form factor (much less than one acoustic wavelength).
- AVH performance is primarily governed by three geometric parameters: length, throat radius, and flare rate.
- Velocity amplification is largely frequency-independent below a specific resonance region.
Conclusions:
- Acoustic velocity horns are effective for particle velocity amplification and directional vector sensing.
- The open-ended configuration is key to AVH functionality, distinguishing them from pressure horns.
- AVHs offer predictable performance based on geometric design, enabling tailored applications.
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