Turbulence measurements using pulsed Doppler ultrasound
Abstract
A demodulating scheme is proposed by relating the statistical probability density functions of velocities inside the region of Doppler sensitivity (i.e., sample volume) to the Doppler shifted signal originating from this region. The first moment of the normalized power spectrum of the Doppler signal received from a sample volume is hypothesized to be the spatially-averaged velocity within it. This demodulator is realized through the use of digital methods and therefore is called the Digital First Moment (DFM) method. Through the use of this DFM method the spatially-averaged velocity can be sampled to obtain the time history from which relevant information about the turbulent flow may be derived. The validity of the proposed model is tested.
- Publication:
-
Ph.D. Thesis
- Pub Date:
- 1978
- Bibcode:
- 1978PhDT........80S
- Keywords:
-
- Flow Measurement;
- Measuring Instruments;
- Turbulent Flow;
- Velocity Measurement;
- Acoustics;
- Doppler Effect;
- Flow Distribution;
- Flow Velocity;
- Pipe Flow;
- Turbulence;
- Ultrasonics;
- Acoustics