Modelling the depth-averaged velocity in trapezoidal meandering channels

Abstract

This paper presents a practical method to predict lateral depth-averaged velocity distribution in trapezoidal meandering channels. Flow structure in meandering channels is more complex than straight channels due to three-dimentional nature of flow. Continuous variation of channel geometry along the flow path associated with secondary currents makes the depth-averaged velocity computation difficult. Design methods based on straight-wide channels incorporate large errors while estimating discharge in meandering channel. Hence, based on the present experimental results, a non-linear form of equation involving three parameters for estimating lateral depth-averaged velocity is formulated. The present experimental meandering channel is wide (aspect ratio = b/h > 5) and with high sinuosity of 2.04. The study serves for a better understanding of the flow and velocity patterns in trapezoidal meandering channel.

Keywords:

• depth-averaged velocity
• discharge
• meandering channels
• flow depth
• secondary currents

Acknowledgement

The writers gratefully acknowledge the Department of Science and Technology (DST), Government of India, for financial support for creating the research facilities in Fluid Mechanics and Hydraulics Laboratory at National Institute of Technology, Rourkela, India. The paper is part of the experimental outcomes created by DST support at the Institute.