Turbulence measurements in a shear layer region of a compound channel

Abstract

The paper describes some turbulence measurements carried out in the SERC Flood Channel Facility at Hydraulics Research Ltd., Wallingford, U.K. The facility represents a large scale model of a river system with floodplains, and is designed to produce fully developed boundary layer flows with transverse shear. This article presents some of the open channel flow data, including measurements of the primary velocity, Ū/u _∗, the distribution of turbulent intensities, u¹/u_∗ , v¹/u_∗ , and w¹/u_∗ , the kinetic energy, k/u2_∗ , and the Reynolds stresses τ_zx and τ_yx in the region of strong lateral shear induced by transverse variation in depth. Attention is focussed on the non linear nature of the Reynolds stresses in the shear layer, flow structures and the lateral variations in eddy viscosity and local friction factor.