Estimation of vegetative hydraulic resistance in an open channel flow (Ayesha and Busari)

Abstract

The Hydraulics of flow in an open channel/waterway with flexible vegetation is studied. Vegetation along waterway has an ecological advantage; it enhances biodiversity, reduces erosion, and traps sediment. However, it has a hydraulic impact on flow. This study reviews hydrodynamics of vegetation along waterways (a concept to promote a sustainable green environment). It applies a modified one-dimensional (1-D) hydraulic model to replicate the vegetative velocity profile and Reynolds stresses using several laboratories experimental and field dataset found in the literature as well as laboratory investigation from the authors. Using this concept, a synthetic velocity profile is generated under varying hydraulic conditions. Using the concept of dimensional similarity, the vegetative parameters and flow resistance equation which relates these vegetation parameters, flow depth, and the zero-displacement parameter is proposed. The findings gave clear and comprehensive deduction, that mathematical model could to an extent replace the rigorous experiments, as evaluations were parallel to the estimated laboratory values.