Turbulence Characteristics in a Rock-Ramp-Type Fish Pass

Abstract

This paper presents the results of an investigation on the turbulence characteristics of a rock-ramp-type, nature-like fish pass with a staggered arrangement of boulders for slopes of 1.5 and 3% for different discharges. This study showed some major differences between the flow with cluster of boulders (wake-interference flow) and the flow with isolated boulders (isolated-roughness flow) in the decay rate of turbulence and turbulence magnitude. General correlations were derived for the turbulence intensity and turbulent kinetic energy (TKE) as a function of normalized streamwise distance in a rock-ramp fish pass. Turbulence statistics (skewness and kurtosis), energy dissipation rate, and dissipative eddy size in this fish pass were also discussed in relation to fish passage.