Scanning acoustic Doppler microscopy and scanning acoustic correlation microscopy

Area of Science:

• Acoustic microscopy
• Microfluidics
• Fluid dynamics

Background:

• Understanding microfluidic flow is crucial for various applications.
• Traditional methods may lack the resolution or non-invasive nature required for microscopic flow analysis.

Purpose of the Study:

• To develop and demonstrate advanced acoustic microscopy techniques for microfluidic flow profiling.
• To analyze the velocity components of fluid flow in front of a microscopic orifice.

Main Methods:

• Utilizing 100 MHz vector contrast acoustic microscopy in a fluid with immersed particles (10 micrometer aluminum flakes).
• Applying scanning acoustic Doppler microscopy and scanning acoustic correlation microscopy.
• Analyzing time-dependent phase and amplitude signals from scattered sound waves using correlation procedures.

Main Results:

• Derived axial velocity profiles from phase contrast in vector contrast acoustic microscopy.
• Demonstrated the capability to resolve normal velocity components.
• Obtained velocity distributions from autocorrelation functions in scanning acoustic correlation microscopy.
• Showcased simultaneous application of both microscopy methods.

Conclusions:

• Vector contrast acoustic microscopy and scanning acoustic Doppler microscopy are effective for microfluidic flow analysis.
• These methods provide detailed insights into velocity profiles, including axial and normal components.
• The techniques offer a powerful tool for studying fluid dynamics at the microscale.