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 Title: Turbulent flow through a rectangular channel Author(s): Niederschulte, Mark Alan Doctoral Committee Chair(s): Hanratty, Thomas J. Department / Program: Chemical and Biomolecular Engineering Discipline: Chemical Engineering Degree Granting Institution: University of Illinois at Urbana-Champaign Degree: Ph.D. Genre: Dissertation Subject(s): Engineering, Chemical Engineering, Mechanical Abstract: Streamwise and normal turbulent velocity measurements were taken at 80 normal locations across a two-inch high rectangular water channel. A two polarization, three beam He-Ne Laser-Doppler Velocimetry system was used. The water channel was specifically designed and constructed to facilitate these optical measurements. It had negligible vibration and flow oscillation. Its length was 200 channel heights, sufficient to produce fully developed turbulent flow. The optical system had a specially designed optical table and traverse; optical glass windows were used as viewing ports.Measurements were made of the first four moments of the velocity fluctuation and the first three moments of Reynolds stress. The turbulence production and the correlation coefficient were calculated. Velocity spectra were measured for both the normal and streamwise velocity fluctuations at four to nine normal locations. Measurements were taken as close as y$\sp+$ = 0.6 viscous units away from the wall. The experiments were conducted at Reynolds numbers of 2457, 2777, and 18,339. The experimental results were compared to the computer simulation channel flow by Kim, Moin, and Moser. Very good agreement was found.Measurements were also made of the differential surface pressure over two sinusoidal waves. Wave amplitudes of 0.0123 and 0.03125 inches were used. Both waves had two inch wavelengths. Viscous fluid was used to extend the range of the measurements over a much larger range of Reynolds numbers than had been previously reported. Non-linearities were found at low Reynolds numbers in the differential pressure distribution over the 0.03125 inch amplitude wave, indicating a quasi-separated or separated flow. The differential pressure distribution over the 0.0123 inch amplitude wave demonstrated a linear, sinusoidal response. The experimental data were compared to computer models developed in this laboratory and were found to demonstrate only fair agreement. This is not unexpected, since the computer models predict a linear response over all experimental Reynolds numbers examined. Issue Date: 1989 Type: Text Language: English URI: http://hdl.handle.net/2142/21640 Rights Information: Copyright 1989 Niederschulte, Mark Alan Date Available in IDEALS: 2011-05-07 Identifier in Online Catalog: AAI8924913 OCLC Identifier: (UMI)AAI8924913
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