Novel Acoustic Methods for Directly Monitoring Seabed Sediment Transport, Geohazards & Scour

该项目将开发和现场测试新的声学方法，用于直接监测和了解海底沉积物运输和冲刷过程，包括海上风电场周围。这些海底过程可能对海上风力设施及其海底电力电缆、电信电缆、石油和天然气管道以及其他战略海底基础设施造成重大地质危害。博士学位最初将基于一系列校准水槽实验，以了解海底沉积物运输或侵蚀过程发出的声学信号的性质。例如，它将确定辐射声的功率谱如何受到流速、推移质输运率和颗粒碰撞强度、存在的颗粒尺寸（砂或中粒）以及密集近床层（例如跳跃颗粒层或片流层）的存在和性质的影响。这些实验室实验（由Simmons在船体监督）将有助于解释声场数据，以更好地监测和了解海底沉积物运移。水听器和/或ADCP数据将用于监测沉积物输运过程和N.海这项工作将使用已经由纽卡斯尔的Neasham获得的水听器数据集。博士将最后分析一系列主要的现场数据集，包括主动沉积物输运过程的水听器记录。它们将包括西非近海、加州和不列颠哥伦比亚省的主要新的野外数据集。这项工作将显示如何利用水听器来了解危险的海底水流以及沉积物迁移和海底冲刷过程，这可能成为未来全球海底监听网络的基础。其目的是进一步测试量化海上风电设施周围沉积物运输所需的声学方法，并利用价值超过320万英镑的两个NERC资助项目提供的现有机会。这种规模的资金根本无法通过CDT本身获得（单个项目的预算最多不到2万英镑）。该项目还将允许学生参加两次大型海洋学巡航，这将使用各种海底测量和监测工具，从而提供出色的实地培训。这是一个很好的培训机会。它还将包括通过分析北海海上风电场附近位置的水听器数据进行培训。

This project will develop and field test novel acoustic methods for directly monitoring and understanding processes of seafloor sediment transport and scour, including around Offshore Wind Farms. These seabed processes can be a significant geohazard to offshore wind installations and their seabed power cables, telecommunication cables, oil and gas pipelines and other strategic seafloor infrastructure. The PhD will be based initially around a series of calibrated flume experiments to understand what determines the nature of acoustic signals emitted by seabed sediment transport or erosion processes. For example, it will determine how the power spectrum of radiated sound is affected by flow speed, bedload transport rates and intensity of grain collisions, grain sizes present (sand or mid), and presence and nature of dense near bed layers (e.g. layers of saltating grains or sheet-flow). These laboratory experiment (supervised by Simmons in Hull) will help to interpret acoustic field data to better monitor and understand seabed sediment transport. Hydrophone and/or ADCP data will then be used to monitor processes of sediment transport and seabed scour near Offshore Wind Facilities in the N. Sea. This work will use hydrophone data sets that are already acquired by Neasham in Newcastle. The PhD will finally analyse a series of major field data sets involving hydrophone records of active sediment transport processes. They will include major new field data sets offshore West Africa, California and British Columbia. This work will show how hydrophones can be used to understand hazardous seabed flows, and processes of sediment transport and seabed scour, which may underpin future global seabed listening networks. The aim here is to further test acoustic methods needed to quantify sediment transport around Offshore Wind Facilities, and make use of existing opportunities provided by two NERC funded projects worth over £3.2 Million. This scale of funding is simply not available through the CDT itself (where budgets for single projects are less than £20k at most). This project will also allow the student to take part in two major oceanographic cruises, which will use a wide range of seabed surveying and monitoring tool, thus providing outstanding field training. They are an outstanding training opportunity. It will also include training via analysis of hydrophone data from locations near Offshore Wind Farms in the North Sea.