Evaluation of a Laser Anemometer for Turbulence Measurements

This 1974 doctoral thesis examines four aspects of laser anemometry for measuring fluid turbulence. First, the effects of receiving optics on the perceived sample volume size, location, and power spectra widths are analyzed. Second, measurements by direct spectral analysis are made in laminar and turbulent pipe flow, with optical parameters adjusted for near-wall measurements. Third, the self-beat signal is analyzed and shown to contain no turbulence information. Finally, FM detection of the laser anemometer signal is demonstrated to yield the one-dimensional turbulent energy spectrum. The sample volume size and scattering particle density are shown to affect the measured spectrum. In each area, a complete theoretical analysis is presented, with emphasis on quality experimental measurements to determine the utility of the laser anemometer. Chemical Engineering Research Report No. 01-04-74. Thesis Advisor: Dr. Robert V. Edwards.