Abstract
A damping characteristics of turbulence intensity were compared between the theoretical model and the experimental data with a laser Doppler anemometer (LDA). The effect of the surface-wave fluctuations was then considered, and the damping effect near the free surface was expressed as a function of the Froude number. Furthermore, Reynolds Stress Model (RSM) was used to calculate the turbulent statistics of open-channel flows in comparison with the experimental data. PIV (Particle-Image Velocimetry) was then used to measure evolutionary patterns of coherent vortices in the center of the channel. Finally, the mean bursting period was evaluated with LDA measurement. By using these methods, a relationship between the “bursting phenomena” and the “boils (surface renewal eddies)” was investigated intensively as a function of the Froude number.
