Velocity measurements for turbulent nonseparated flow over solid waves
Abstract
LaserDoppler velocimetry measurements have been made of nonseparated velocity fields over solid sinusoidal wavy surfaces. Timeaveraged velocity and turbulent intensity data are given. The measurements were conducted over waves on the bottom wall of a rectangular channel with a cross section of twenty four by two inches, the two inch dimension being vertical. Two sets of velocity data were obtained at conditions corresponding to flows where linear and nonlinear shear stress responses are observed. The conditions were wave steepnesses 2a lambda, and channel Reynolds numbers of 0.03125, 6400, and 0.05, 38,800 respectively. The wavelength of the waves was two inches. The viscous wall region was of particular interest. Sufficient measurements were taken to give an accurate representation of both the streamwise and normal variation of the viscous wall region. The data was Fourier analyzed to determine the extent of nonlinearities, the wavelength average flowfields, and the amplitudes and phases of the velocity responses. The physical meaning of the data is interpreted in terms of pressure gradient effects along the wave surfaces. Comparisons of the data with prediction from simple eddy viscosity models are also given.
 Publication:

Progress Report
 Pub Date:
 December 1985
 Bibcode:
 1985uill.rept.....F
 Keywords:

 Flow Distribution;
 Fourier Analysis;
 Laser Doppler Velocimeters;
 Turbulent Flow;
 Velocity Measurement;
 Viscous Flow;
 Vortices;
 Amplitudes;
 Computer Programs;
 Lasers;
 Pressure Gradients;
 Reynolds Stress;
 Shear Stress;
 Sine Waves;
 Stress Measurement;
 Surface Properties;
 Walls;
 Fluid Mechanics and Heat Transfer