Sonic Characterisation of Water Surface Waves, Turbulence, Mixing and Bed Friction in Shallow Water Flows

浅水流中水面波、湍流、混合和床层摩擦的声波表征

• 批准号: EP/G015341/1
• 负责人: Simon Tait
• 金额: $ 47.87万
• 依托单位: University of Bradford
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2009
• 资助国家: 英国
• 起止时间: 2009 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FG015341%2F1
• 关键词: Sonic; Characterisation; Water; Surface; Waves

Flows found in many situations including gravel bed rivers, overland flows, and in partially filled pipes are turbulent. Such depth-limited flows always have patterns of small waves on the air/water boundary. We believe that the dynamic behaviour of these small waves carries information about the turbulent mixing and energy losses within that flow. Normally in engineering calculations the water surface is assumed to be flat and so this source of potentially very valuable information is ignored. This project will use laboratory observations and a complex 3D numerical model to study and predict the turbulent flow structures that are created by turbulent flows over rough solid boundaries. These flow structures then rise to the water surface and cause it to oscillate and create a distinct pattern of small waves. The numerical model will be able to predict the generation, growth and transport of these flow structures in 3D, and capture their effect on the water surface pattern. It is believed that by measuring the wave pattern it will be possible to predict the mixing and energy losses within the flow. The numerical model will be used to simulate this process for a wide range of physical scales, bed roughness types and flow depth to width ratios, so that a very wide range of flow regimes will have been examined.The wave pattern on a water surface can be measured using a number of methods; e.g. optical, eletromagnetic and acoustic. Acoustic measurements are particularly suited to hydraulic applications because they are fast, low-cost, non-invasive, and can be easily used at both small and large scales. An airborne acoustic sensor that can project sound energy onto the moving water surface pattern will be placed above the water surface in a channel or pipe. By examining the acoustic reflections, the behaviour of the air-water boundary will be measured. New methods of acoustic signal analysis and sound propagation theory are needed to re-construct the fine detail of the water surface patterns from the measured acoustic reflections. The processed acoustic data will then be combined with the knowledge gained from the laboratory and 3D numerical studies to provide engineers with relationships to estimate energy losses and turbulent mixing solely from measurements of the air-water boundary. Information on energy losses and turbulent mixing is needed to predict water levels for flood studies and to predict the mixing of pollutants and sediments accidentally released into rivers and pipes. This system will be able to improve flood prediction and warning, so providing better protection for people and their property. Better assessment of turbulent mixing in water bodies will help to protect better the natural environment and sensitive habitats. In the final part of the project, a prototype sensor system will be manufactured and tested at full scale in the River Taff, at an Environment Agency test facility. The results will be used to demonstrate the practical applicability of the concept and the technology to end users.

在许多情况下，包括砾石河床河流、漫流和部分充满的管道中，流动都是湍流。这种深度有限的流动在空气/水边界上总是具有小波图案。我们相信，这些小波浪的动态行为携带了有关湍流混合和能量损失的信息。通常在工程计算中，假定水面是平坦的，因此忽略了这一潜在的非常有价值的信息来源。该项目将使用实验室观测和复杂的3D数值模型来研究和预测湍流在粗糙固体边界上产生的湍流结构。然后这些流动结构上升到水面，使其振荡并产生独特的小波浪图案。该数值模型将能够预测这些流动结构的生成、增长和运输，并捕捉它们对水面模式的影响。据信，通过测量波型，将有可能预测流内的混合和能量损失。数值模型将用于模拟这一过程的各种物理尺度，床粗糙度类型和流动的深宽比，以便检查非常广泛的流动状态。水面上的波型可以使用多种方法测量，例如光学，电磁和声学。声学测量特别适合于液压应用，因为它们快速，低成本，非侵入性，并且可以很容易地在小规模和大规模上使用。可以将声能投射到移动的水面图案上的机载声学传感器将被放置在通道或管道中的水面上方。通过检查声反射，将测量空气-水边界的行为。需要声信号分析和声传播理论的新方法来从测量的声反射重构水面图案的精细细节。然后，将处理后的声学数据与从实验室和3D数值研究中获得的知识相结合，为工程师提供仅从空气-水边界测量值估计能量损失和湍流混合的关系。需要关于能量损失和湍流混合的信息来预测洪水研究的水位，并预测意外释放到河流和管道中的污染物和沉积物的混合。该系统将能够改善洪水预测和预警，从而为人民及其财产提供更好的保护。更好地评估水体中的湍流混合将有助于更好地保护自然环境和敏感生境。在该项目的最后一部分，原型传感器系统将在塔夫河的环境署测试设施中进行全尺寸制造和测试。研究结果将用于证明该概念和技术对最终用户的实用性。

项目成果

A model of the free surface dynamics of shallow turbulent flows

• DOI: 10.1080/00221686.2016.1176607
• 发表时间: 2016-01-01
• 期刊: JOURNAL OF HYDRAULIC RESEARCH
• 影响因子: 2.3
• 作者: Nichols, Andrew;Tait, Simon J.;Shepherd, Simon J.
• 通讯作者: Shepherd, Simon J.

SPH modelling of depth-limited turbulent open channel flows over rough boundaries.

深度限制的湍流开放通道的SPH建模在粗糙的边界上流动。

• DOI: 10.1002/fld.4248
• 发表时间: 2017-01-10
• 期刊: International journal for numerical methods in fluids
• 影响因子: 1.8
• 作者: Kazemi E;Nichols A;Tait S;Shao S
• 通讯作者: Shao S

SPHysics simulation of laboratory shallow free surface turbulent flows over a rough bed

• DOI: 10.1080/00221686.2017.1410732
• 发表时间: 2018-01-01
• 期刊: JOURNAL OF HYDRAULIC RESEARCH
• 影响因子: 2.3
• 作者: Gabreil, Eslam;Tait, Simon J.;Nichols, Andrew
• 通讯作者: Nichols, Andrew

An eigenvalue correction due to scattering by a rough wall of an acoustic waveguide.

由于声波导的粗糙壁的散射而进行的特征值校正。

• DOI: 10.1121/1.4812757
• 发表时间: 2013
• 期刊: The Journal of the Acoustical Society of America
• 作者: Krynkin A

The pattern of surface waves in a shallow free surface flow

• DOI: 10.1002/jgrf.20117
• 发表时间: 2013-09-01
• 期刊: JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
• 影响因子: 3.9
• 作者: Horoshenkov, K. V.;Nichols, A.;Maximov, G. A.
• 通讯作者: Maximov, G. A.