【作者】 刘华兴；

【导师】 于定勇；

【作者基本信息】 中国海洋大学 ， 港口、海岸及近海工程， 2010， 博士

【摘要】 海浪是海洋中最常见的现象之一,是岸滩演变的重要动力和海岸工程结构物设计施工的主要考虑因素,对海洋经济、海洋资源的开发利用,海上军事活动,海洋工程的选址、规划、设计、施工和日常营运等均有重大影响。海浪的观测与计算不仅有助于了解海浪的生成、生长机制,搞清海浪的内部结构和外在特征,还可为港口与桥梁的设计及海洋石油平台的建造等海洋工程提供所必需的海浪参数。随着科技的不断发展,以及海洋环境的特殊性,对测波仪器的性能提出了更高的要求。根据传统测波方法的现状和现场监测的需要,基于水听器和同步压力传感器在波浪频率范围内带通滤波后的信号一致这一观测事实,本文提出了一种简便快捷和经济实用的被动声学测波方法。该方法通过对滤波后的声学信号进行谱估计,得到的声压谱经传递函数和补偿因子修正后,即可得到表面波谱,进而计算统计波浪要素。基于该原理,借助于虚拟仪器开发平台,通过软硬件的合理结合,设计开发出了一套准确高效、界面友好的便携式声学测波系统。在实验室初步验证后,先后两次分别将该系统应用于莱州湾及芝罘岛的海上监测,并对比压力测波法同步测量数据,表明被动声学测波方法所测的波浪要素是合理可靠的。该系统具有较强的可扩展移植性,满足海洋观测任务多样性的需求。结合水听器测量波面破碎的原理,本文扩展了该被动声学测波系统,使之可同时获得波面破碎和波群信息；根据现有观测资料,对前人提出的破碎和群性之间的定性关系进行了验证。由于破碎和波群信息均由同一个水听器获得,保证了测量信息的同步性,使二者关系的分析更加可靠,结果更加可信。基于风浪破碎统计特征的理论模式,结合水听器测量波浪破碎的原理,本文进一步将该被动声学测波系统应用至海面天气的探测。通过水听器测量平均周期和破碎率等参数,合理的反演出海面局地风速；通过水听器信号的方差分析,估计海面的降雨信息。该系统充分发挥了其水下无接触测量的优势,具有安全、隐蔽和易于移动的优越性,尤其适合于海洋军事的需要。更多还原

【Abstract】 Surface waves are one of the most common phenomena in the sea, which act as important dynamics in beach evolution and must be properly addressed in both design and construction of coastal structures. It also plays a principle role in marine economy, marine resources exploitation and utilization, marine military affairs, as well as location, planning, designing, construction and daily operations of ocean engineering. The observation and computation of ocean waves not only helps to understand its formation and growth mechanism, find out its internal structures and external characteristics, but provides essential parameters for ocean engineering, such as designing of ports & bridges, construction of oil platforms, etc. Nowadays, the developing of science & technology and particularity of marine environments give rise to higher aspiration for the performance of wave measurement instruments.Based on the current development of wave measurements and requirements of in situ observations, as well as the truth that a hydrophone has unanimous signals with a simultaneous pressure sensor after bandpass filtering with the passband of wave frequency, a new wave measurement using underwater passive acoustics is proposed, which is quick, convenient, economic, and practical. It estimates the spectrum of filtered signals, and amend it with a transfer function and a compensation factor to get the surface spectrum, then obtain statistical wave parameters like significant wave height and period. A portable wave measurement system is then specially designed and developed by use of virtual instrumentation, which is efficient and user friendly. After the laboratory validation, the system is used in field measurements in Laizhou Bay and Zhifu Island, respectively. It shows a good result comparing to the simultaneous pressure sensor data. The system is easily extendable, which meets the variability of ocean measurements. It is then extended to explore the relation between wave breaking and groupiness, since it can get breaking events and envelopes simultaneously by using only one hydrophone, which makes the results more reliable and reasonable.The system is also applied to detection of surface weather from underwater, based on the theoretical model of wave breaking statistics:to predict wind speed at sea surface by measuring the mean wave period and breaking probability using a hydrophone; to predict the precipitation by analyzing the variance of sound spectrum level. Taking its advantage of operating safe and non-intrusively, the system is concealed and easy to move, especially suitable for submarines.更多还原