SMARTY - Supergen MARrine TechnologY challenge

任何暴露在破碎波浪中的结构，无论是简单的防波堤还是复杂而昂贵的海洋能源机器，都将暴露在高波浪冲击载荷下，因为倾覆的波峰猛烈撞击它。波浪破碎时水面运动的剧烈程度对于寻求这种条件的冲浪者是众所周知的。海洋可再生能源设备将受到自然界可能产生的最猛烈的风暴的袭击，但它们需要在天气温和且海浪相对较小的情况下产生大量电力。这种二分法可能会导致昂贵的故障，例如位于苏格兰北海岸的2 MW波浪能原型设备Osprey在风暴中受损并沉没。如果海洋可再生能源要在满足联合王国的能源需求方面发挥重要作用，所有能源提取装置都必须能在许多年和许多大风暴中不受损坏。因此，需要准确的设计方法来估算此类风暴中发生的峰值水动力载荷。本项目探讨确保可再生能源设备在极端条件下生存所需的科学和工程，并寻求确定设备在不太恶劣的条件下运行的上限。在生存能力方面取得重大进展的关键是了解陡峭和猛烈的波浪如何在重要的水流中表现出来。波浪发电机和海流涡轮机都可能位于相对较浅的水域，具有相对较快的潮流，显然对于潮汐涡轮机来说，这是一个优点！如果水流很快，水很浅，靠近海床的水流会有相当大的阻力，而向上流到水面的阻力就小了。因此，电流很可能是高度剪切和非常动荡的。加上这股大规模的水流，猛烈地推翻了陡峭的波浪，很明显，水将在局部地区移动得非常快。该项目的第一部分是描述波浪的统计数据，以及这些数据在几十年到几十年的时间内如何变化。接着，波浪与剪切流结合。然后，海洋可再生能源设备的模型将暴露在这种剧烈的波浪和水流事件的组合下，并测量这些力。最后，我们的目标是开发和测试力计算机为基础的计算方法，评估负载。这一研究项目的总体产出将为消除限制和减缓大规模实施海洋可再生能源的障碍作出重要贡献。

Any structure exposed to breaking waves, be it a simple breakwater or a complex and expensive marine energy machine, will be exposed to high wave impact loads as overturning wave crests slam into it. The violence of the motion of the water surface as waves break are well-known to surfers who seek out such conditions. Marine renewable energy devices will be hit by the most violent storms that nature can produce, yet they are required to produce significant power when the weather is benign and the waves relatively small. This dichotomy can result in expensive failures such as that of the Osprey, a 2MW wave power prototype device located off the north coast of Scotland, which was damaged and sank in a storm. If marine renewable energy is to play a significant role in meeting the energy requirements of the the United Kingdom, all energy extraction devices must survive for many years and many large storms without damage. Hence accurate design methods are required to estimate the peak hydrodynamic loads occurring in such storms.This project explores the science and engineering required to ensure that renewable energy devices survive extreme conditions, and seeks to identify the upper limit of device operations in less severe conditions. Key to making a significant advance in survivability is understanding how steep and violent waves behave on significant currents. Both wave power machines and marine current turbines are likely to be located in relatively shallow water with relatively fast tidal currents, obviously for tidal turbines this is a virtue! If the current is fast and the water shallow, there will be considerable resistance to the flow close to the sea-bed and less further up towards the surface. Thus, the current is likely to be highly sheared and very turbulent. Add on top of this bulk flow violently overturning steep waves and it is clear that the water will be moving around very fast in local regions. The first part of this project is to characterize the statistics of waves and how this varies over time for decades to decades. Next the waves are combined with sheared currents. Then models of marine renewable energy devices will be exposed to such violent combined wave and current events and the forces measured. Finally we aim to develop and test force computer based computational methods for assessing loads. The overall output from this research project will make an important contribution to removing blocks limiting and slowing down the large-scale implementation of marine renewable energy.