A 3-D PW ultrasonic Doppler flowmeter: theory and experimental characterization

Area of Science:

• Fluid Dynamics
• Biomedical Engineering
• Ultrasound Technology

Background:

• Quantitative fluid velocity measurement is crucial in various scientific and engineering fields.
• Existing methods may have limitations in spatial resolution or directional ambiguity.
• Accurate velocity vector field mapping requires advanced measurement techniques.

Purpose of the Study:

• To develop and validate a complete 3-D ultrasonic pulsed Doppler system.
• To enable quantitative measurement of fluid flow velocity vectors independent of probe position.
• To assess the accuracy of the developed 3-D Doppler technique.

Main Methods:

• A probe with four piezocomposite ultrasonic transducers (1 central transmitter, 3 receivers) was utilized.
• Velocity projections were measured along three distinct directions using Doppler shift.
• Analog phase/quadrature demodulation and digital processing extracted mean velocity from complex spectra.

Main Results:

• The system successfully measured the velocity vector field of fluid flow.
• Accuracy was tested on a moving string phantom.
• An error of approximately 4% in both amplitude and direction was achieved with a 100 ms acquisition window.

Conclusions:

• The developed 3-D ultrasonic pulsed Doppler system provides quantitative fluid velocity vector measurements.
• The system demonstrates high accuracy and independence from probe positioning.
• This technique offers a promising tool for fluid flow analysis.