International Collaboration between Japan and Germany on Experimental and Numerical Studies of Turbulent Structure in Open-Channel Backward-Facing Step Flows

Abstract

An international collaboration on experimental and numerical studies of turbulent openchannel step flows has been conducted between Kyoto University and University of Erlangen-Nürnberg. The experiments were carried out with high accurate two-component Laser Doppler anemometer (LDA) in open-channel step flows, whereas the calculations were conducted using k-ε turbulence model with colocated (non-staggered) variable arrangement. Five test cases with different Reynolds and Froude numbers (see Table 1) were considered. The very good agreement of the calculations with the experimental data was obtained not only for mean velocity distributions, but also for turbulence characteristics such as the turbulent energy κ, Reynolds stress-uv and turbulent dissipation ε.The reattachment length could be predicted accurately.