Effects of vegetation on open channel flow

Abstract

The report describes the effects of vegetation on open channel flow. Due to the presence of vegetation, the flow is affected by the drag force. Therefore, the flow property becomes much different from the non-vegetated flow. It has been an interest of research for a long time, to which many scholars have contributed their initiatives in order to improve the description of those effects.

The study was carried out in Hydraulics Modeling Lab in School of Civil and Environmental Engineering (CEE), Nanyang Technological University (NTU). There were three different experimental instruments involved in the project, namely Stremflo Velocity Meter (SVM), Electromagnetic Current Meter (EMCM) and Laser Doppler Anemometer (LDA). Most of the data discussed in this report was collected using the LDA.

In the flume experiments, six kinds of simulated vegetation models were tested with a fixed flume bed slope. By analyzing four main parameters including flow discharge, hydraulic roughness, velocity distribution and turbulence structure, the effects of vegetation on uniform flows are identified and a number of conclusions are finally drawn.