The 17-Meter Flume at the Coastal Research Laboratory. Part 2. Flow Characteristics
Abstract
This report summarizes the characteristics of the idealized one-dimensional turbulent channel flow for which the 17-Meter Flume was designed, and describes a measurement program designed to determine whether the flume can in fact produce such a flow. The measured quantities include mean velocities, Reynolds stresses, turbulence intensities and velocity spectra. Measured profiles on mean velocity, Reynolds stress and turbulence intensities are consistent with previous theoretical and empirical results. Measured spectra, although consistent with expectations over a wide range of frequencies, indicate a few unexpected features, including a constant spectral density at high frequencies (possibly due to aliasing or high frequency noise) motion at few well-defined high frequencies of order 10 hz (possibly due to structural vibrations), oscillations with time scales of order 30 s (possibly due to low-mode standing surface waves) and irregular motions with time scales of several minutes (possibly due to fluctuations in pump performance). The unexpected features indicated by the spectra at high and low frequencies do not have a significant effect of mean velocities and low-order statistics, but they may be important in some applications. Keywords; Turbulent channel flow; Boundary layer; Flow measurements; Fluid dynamics. (KT)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1989
- Accession Number
- ADA213288
Entities
People
- Cheryl A. Butman
- John H. Trowbridge
- Robert J. Chapman
- Wayne Rockwell Geyer
Organizations
- Woods Hole Oceanographic Institution