Evaluating the efficacy of particle image velocimetry to estimate surface flow velocity in vegetated rivers

评估粒子图像测速法估算植被河流表面流速的效果

• 批准号: 2740735
• 金额: --
• 依托单位: University of Reading
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2740735
• 关键词: Evaluating; efficacy; particle; image; velocimetry

Aquatic plants are prevalent in lowland rivers and they exert a dominant influence on river hydraulics. Flow resistance (via Manning's Roughness Coefficient) has been shown to change seasonally in response to macrophyte growth, were higher values for Manning's n tend to be recorded during periods when there is a greater abundance of aquatic plants in the water column (Naden et al 2006). The increase in flow resistance caused by an abundance of aquatic vegetation growing in the channel has the effect of decreasing the flow velocity of water, which in turn can increase the water's depth and enhance the chance of flooding. Particle Image Velocimetry (PIV) is a well-established technique for measuring velocity fields in macroscopic fluid systems and this image-based approach is considered a suitable method for estimating surface flow velocities (Sun et al 2010). However, very few attempts have been made to estimate surface flow velocities using PIV technology for heavily vegetated rivers. Given that aquatic plants have a significant influence on river hydraulics, it is necessary for flood control and water supply to measure surface flow velocities in vegetated rivers. This project aims to evaluate the efficacy of PIV to estimate surface flow velocities in vegetated rivers. The PIV results will be compared with those measured by an (in-situ) Acoustic Doppler Velocimeter (ADV), which is one of the most popular instruments for measuring flow velocities, to evaluate their accuracy

水生植物在低地河流中很普遍，它们对河流液压产生了主导的影响。流动电阻（通过曼宁的粗糙度系数）已显示出对大植物生长的季节性变化，在水柱中有更多丰富的水生植物时，曼宁的N往往会记录较高的值（Naden等人2006年） ）。通道中大量水生植被引起的流动阻力增加的作用是降低水的流速，进而可以增加水的深度并增加洪水的机会。粒子图像速度法（PIV）是一种良好的技术，用于测量宏观流体系统中的速度场，而这种基于图像的方法被认为是估计表面流速度的合适方法（Sun等，2010）。但是，很少有人尝试使用PIV技术来估算表面流速度，以进行大量的植被河流。鉴于水生植物对河流液压的影响很大，因此需要防洪和供水才能测量植被河流中的表面流速。该项目旨在评估PIV估计植被河流中表面流速的功效。 PIV结果将与通过（原位）原声多普勒赛车仪（ADV）测量的结果进行比较，这是测量流速最受欢迎的工具之一，以评估其准确性