An experimental study of large waves in intermediate and shallow water depths. Part I: Wave height and crest height statistics
An experimental study of large waves in intermediate and shallow water depths. Part I: Wave height and crest height statistics
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DOI：
10.1016/j.coastaleng.2012.09.007
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发表时间：
2013-03
影响因子：
4.4
通讯作者：
V. Katsardi;L. D. Lutio;C. Swan
中科院分区：
文献类型：
--
作者：
V. Katsardi;L. D. Lutio;C. Swan
本文介绍了一系列的实验室观测进行了专门建造的波浪水槽。这项研究的目的是模拟一系列现实的海洋光谱，这些光谱在一些温和的海床坡度（m）上演变;所选择的海况允许对当地水深、光谱峰值周期、有效波高、光谱带宽和海床坡度的作用进行系统调查。本文的重点在于波高（H）和波峰高程（ηc）的统计分布;实验室数据用于理解各种参数的重要性，并评估通常采用的设计分布。研究结果表明，波高和峰高分布主要取决于有效水深（kpd）和海况陡度（1/2 Hskp），其中kp是谱峰对应的波数，d是水深，Hskp是有效波高。相反，这些分布与平缓的河床坡度（m1≤/100）和光谱带宽无关;后者的结果与深水中出现的结果非常不同。经过详细的比较，在很宽的参数范围内，深水深度（kpd>1.0）的波高分布与（Forristall，1978）和（Glukhovskii，1966）分布相当一致;随着破碎波比例的增加，后者变得更加重要。随着水深的减小，（Mendez等人，2004）分布以及（Battjes & Groenendijk，2000）复合威布尔分布（CWD）变得越来越适用。然而，不同的陡度，但与所有其他参数保持不变的海况之间的比较表明，后一种解决方案所依据的经验参数可能不是普遍适用的。最后，在最浅的水深（kpd ≥ 0.5），现有的分布没有提供一个很好的描述的测量数据，所有导致高估的最大波高。
This paper describes a series of laboratory observations undertaken in a purpose-built wave flume. The objective of the study was to simulate a range of realistic ocean spectra evolving over a number of mild bed slopes (m); the chosen sea states allowing a systematic investigation of the role of local water depth, spectral peak period, significant wave height, spectral bandwidth and bed slope. The focus of the present paper lies in the statistical distribution of both the wave height (H) and the wave crest elevation (ηc); the laboratory data being used to provide both an understanding of the importance of the various parameters and an assessment of the commonly adopted design distributions. The results of the study have shown that both the wave height and the crest height distributions are primarily dependent upon the effective water depth (kpd), where kpis the wave number corresponding to the spectral peak and d the water depth, and the sea state steepness (1/2Hskp), where Hsis the significant wave height. Conversely, the distributions are independent of the mild bed slope (for m1≤/100) and the spectral bandwidth; the latter result being very different to that which arises in deep water. Following detailed comparisons, across a wide parameter range, the wave height distributions in the deeper water depths (kpd>1.0) are shown to be in reasonable agreement with the (Forristall, 1978) and (Glukhovskii, 1966) distributions; the latter becoming more important as the proportion of breaking waves increases. As the water depth reduces, the (Mendez et al., 2004) distribution as well as the (Battjes & Groenendijk, 2000) composite Weibull distribution (CWD) become increasingly applicable. However, comparisons between sea states of varying steepness, but with all other parameters held constant, suggest that the empirical parameters on which the latter solution is based may not be universally applicable. Finally, in the shallowest water depths (kpd≈0.5), none of the existing distributions provide a good description of the measured data; all leading to an over-estimate of the largest wave heights.