Comparison of turbulent intensity component of the stratified flow in the braided river with different upstream flowrates

摘要

The physical model experiment was carried out to study the effect of velocity ratio of two layers on the turbulence intensity of stratified flow in the typical braided rivers with two symmetrical anabranches. Two velocity ratios were selected, and the distributions of depth-averaged turbulent intensity component in the left anabranch were analyzed. When velocity ratio became smaller, the turbulent intensity increased and peak turbulent intensity zone transferred from the left area of centerline to the right area of centerline at the section before the bend apex of the anabranch. In the outlet section of the anabranch, turbulent intensity increased at the inner bank. The distributions of lateral-averaged turbulence intensity components in the vertical sections of left anabranch were also analyzed. Turbulence intensity component in the interface of hot and cold water was both high in two velocity ratios. As water flowed downstream, the difference of turbulent intensity component in the vertical direction decreased obviously.