Three-dimensional turbulent boundary layer flow over a spinning cylinder

摘要

Two sets of experiments are reported for a three-dimensional turbulent boundary-layer flow over a spinning cylinder, with and without a pressure gradient, which was produced by a forward-facing-step obstruction. Additional measurements are reported for two-dimensional flow over the same cylinder (nonspinning), with and without a pressure gradient. The data are presented in tables. The cylinder, which is axially aligned with the flow, contains three sections: an upstream stationary section, a central spinning section (where the flow develops a lateral component), and a downstream stationary section (where the flow's lateral component decays). Measurements were acquired primarily on the downstream stationary section and include all 3 components of mean velocity, all 6 Reynolds stresses, and 10 triple-velocity-product correlations. Surface pressure and skin friction were also measured. The data indicate that Reynolds shear stress is not simply proportional to mean-flow strain rate and that significant anisotropies develop in eddy viscosities. Also, the streamwise pressure gradient is seen to alter streamwise velocity and Reynolds stress without significantly affecting transverse velocity and Reynolds stress. Calculations using a Reynolds-stress equation model predict the mean flow reasonably well. Both corrected (for possible velocity biases) and uncorrected data are reported and stored on the floppy disk attached so that when future research on velocity bias is available an informed decision can be made as to which of the data sets to use.