開水路流れの壁面せん断力分布と縦渦に関する実験的検討 (1)

Abstract

Open-channel turbulent flows often present three dimensional aspects because of the exis-tence of the longitudinal eddies. The longitudinal eddies can be separated into those of the firstkind (originated from the shape of the cross-section) and those of the second kind (rerated to thebursting phenomenon in the boundary layer).In this paper the characteristics of the longitudinal eddies in the small width-to-depth ratiochannel are investigated using experimental results of the boundary shear stress distribution, sand-ridges visualized by Cameron effect and velocity vectors measured by laser doppler anemome-ter. Experimental results show that the shape of the cross-section has an effect on the arrange-ment, stability and scale of the longitudinal eddies.