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1.
台湾海峡及其邻近海域灾害性海浪的时空分布 总被引：3，自引：0，他引：3
据１９６６～１９９３年台湾海峡及其邻近海域灾害性海浪观测资料的统计分析得出,东海灾害性海浪平均每年出现１１．４６次,台湾海峡为７．２９次,台湾以东洋面及巴士海峡为１０．１１次;该区灾害性海浪出现次数有显著的年际和月际变化。这些结果可为台湾海峡区域海洋学的发展提供有意义的素材,也为防灾减灾,做好灾害性海浪短期预报和中、长期预测提供一条有效途径。 相似文献
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3.
Circulation and hydrology of Manukau Harbour 总被引：1，自引：1，他引：0
Abstract Current meter and current drogue measurements made over tidal periods show that the circulation in Manukau Harbour is mainly tidal, with strongest flows within the inner harbour in the four main channels. In the entrance channel, peak tidal speeds reach 2.25 m.s?1 at the surface, and 0.6 m.s?1 near the bottom. Salinity and temperature observations show that the water is nearly homogeneous with depth in summer. A residence time of 22 d is calculated, assuming the small horizontal salinity contrast is maintained by freshwater inflow and evaporation. 相似文献
4.
The joint distribution of wave heights and periods of individual waves is usually approximated by the joint distribution of apparent wave heights and periods. However there is difference between them. This difference is addressed and the theoretical joint distributions of apparent wave heights and periods due to Longuet-Higgins and Sun are modified to give more reasonable representations of the joint distribution of wave heights and periods of individual waves. The modification has overcome an inherent drawback of these joint PDFs that the mean wave period is infinite. A comparison is made between the modified formulae and the field data of Goda, which shows that the new formulae consist with the measurement better than their original counterparts. 相似文献
5.
采用TOMAWAC模型模拟近岸40年的波浪要素。波谱计算采用36个方向,模拟波周期范围为1.5～29 s,并对极值波况进行分析。统计了1979—2018年间有效波高的年极值,算得百年一遇的有效波高,发现百年一遇波高由北往南总体呈现增大趋势:渤海和黄海的百年一遇的波高不超过10 m;东海百年一遇的波高在15～22 m之间;南海北部百年一遇波高的范围比较大,靠近台湾部分最大达到了22 m,海南岛西部较小,在10～15 m之间。引用SET值相关指标对极端波浪的发生次数、持续时间和强度进行分析,发现渤海、黄海北部、台湾海峡以及南海西北部极端事件频繁发生,平均每年有5～7次,台湾岛西南部极端事件的平均历时最大,达到了32 h。 相似文献
6.
综述第27届国家海岸工程会议（ICCE2000）上有关海浪特性及其传播变形研究的新进展，内容包括海浪的时域特性，海浪的特征，海浪的传播变形和波浪的破碎，反射等四部分。 相似文献
7.
总结分析了2012年中国近海有效波高≧4 m的灾害性海浪过程及灾情概况,并对2012年度的预测结果进行了检验评估。依据1968—2012年有效波高≧4 m的灾害性海浪的统计资料,结合2013年副热带高压及热带风暴的分析预测资料,预测了2013年中国近海灾害性海浪过程的出现次数,以及分海区的出现天数,预测结果可为今年的海洋防灾减灾提供技术支持。 相似文献
8.
中国近海2011年灾害性海浪分析及2012年预测 总被引：1，自引：0，他引：1
总结分析了2011年中国近海有效波高为4 m以上的灾害性海浪过程及灾情概况,并对本年度的预测结果进行了检验评估。依据1968—2011年有效波高≧4 m的灾害性海浪的统计资料,结合2012年副热带高压及热带风暴的分析预测资料,预测了2012年中国近海灾害性海浪过程的出现次数,以及分海区的出现天数,预测结果可为今年的海洋防灾减灾提供技术支持。 相似文献
9.
Hsien-KuoCHANG Jin-ChengLIOU 《中国海洋工程》2004,18(3):371-380
This investigation examines long wave reflection and transmission induced by a sloping step. Bellman and Kalaba‘s (1959) invariant imbeddlng is introduced to find wave reflection. An alternative method matching both the surface elevation and its surface slope of each region at the junction is applied to the determination of wave reflection and transmission.The proposed methods are compared with the accurate numerical results of Porter and Porter (2000) and those of Mei (1983) for a vertical step. The wave reflection obtained for a mildly sloping step differs significantly from the result of Mei. The wave reflection is found to fluctuate owing to wave trapping for the ntild sloping step. The height and the face slope of the step are important for determining wave reflection and transmission coefficients. 相似文献
10.
斜向不规则波对直墙作用的实验研究 总被引：5，自引：1，他引：5
通过长峰不规则波和方向波谱对直墙作用的实验研究 ,分别给出了每延米斜向不规则波波浪力与正向力之比 ,方向波谱波浪力与斜向长峰不规则波波浪力之间的关系 ,通过与规则波实验结果的比较给出了斜向规则波与不规则波波浪力之间的相对关系 ;并对斜向不规则波的反射系数与正向波时的变化作出了分析 相似文献
11.
本文以南麂海洋站１９８３～１９９０年风、浪的实测资料为依据，建立了南麂海城春、夏、秋、冬季定常波风浪波高与风速的经验关系式。检验结果表明，曲线回归显著，计算值与实测值吻合良好。文中还对偏ＮＮＥ向和偏ＳＳＷ向计算波高随风速增大的快慢，同一方向在同一风速作用下计算波高的季节变化及其机理作了初浅的讨论。 相似文献
12.
Weng Keqin
Associate Professor Hydraulic Hydro-Power Engineering Dept. Tsinghua University Beijing 《中国海洋工程》1995,(2)
This paper reveals that the long-period statistic distribution of the characteristic heights of deep-water waves assumes the lognormal distribution. Thereafter, the largest wave-height which may occur in the service life of coastal structures is derived in this paper. 相似文献
13.
The physical simulation method of wave groups in a wave flume is proposed and verified by the exper- iments. The experimental results demonstrate that random waves with desired wave groupiness, which simultaneously includes the wave group height and length, can be generated satisfactorily at the specified position in a wave flume using the proposed method. Furthermore, the transformation properties of the wave groupiness along the fiat-bottomed wave flume are investigated based on the physically simulated waves. Associated proposals with the physical simulation of wave groups are given. 相似文献
14.
Wave radiation stress is the main driving force of wave-induced near-shore currents. It is directly related to the hydrodynamic characteristics of near-shore current whether the calculation of wave radiation stress is accurate or not. Irregular waves are more capable of reacting wave motion in the ocean compared to regular waves.Therefore, the calculation of the radiation stress under irregular waves will be more able to reflect the wave driving force in the actual near-shore current. Exact solution and approximate solution of the irregular wave radiation stress are derived in this paper and the two kinds of calculation methods are compared. On the basis of this, the experimental results are used to further verify the calculation of wave energy in the approximate calculation method. The results show that the approximate calculation method of irregular wave radiation stress has a good accuracy under the condition of narrow-band spectrum, which can save a lot of computing time, and thus improve the efficiency of calculation. However, the exact calculation method can more accurately reflect the fluctuation of radiation stress at each moment and each location. 相似文献
15.
Gu Jialong Shen Xianrong
Professor Hohai University Nanjing
Engineer The Investigation Design Institute Bureau of Communications of Zhejiang Province Hangzhou 《中国海洋工程》1991,(2)
In accordance with the similarity between breaking waves and hydraulic jumps, the expressions for estimating wave decay and wave energy dissipation in the surf zone are derived based on the fundamental equations of fluid mechanics. Using the numerical solution of cnoidal wave theory, the various kinematic properties of waves in the surf zone, including the relative wave crest height, wave energy, and radiation stress are discussed. The values calculated with the method proposed in this paper are in good agreement with the experimental data gained by other researchers. The present expressions can be used in the studies of sediment transport on gently sloping beaches, especially on muddy beaches. 相似文献
16.
W. J. Hastie 《新西兰海洋与淡水研究杂志》2013,47(4):507-515
Wave data are presented for Timaru, New Zealand, based on instrumental records collected between October 1981 and October 1982. Significant wave height ranged from 0.32–3.33 m with a mean value of 0.97 m. Significant wave period ranged from 5–17 s with a mean value of 10 s. The maximum wave height recorded was 6.30 m. A marked variation was found between summer and winter conditions. Winter months displayed a much greater range of wave conditions, significant heights were generally higher and significant periods longer. 相似文献
17.
Saleh Abdalla 《Marine Geodesy》2015,38(3):365-380
SARAL/AltiKa surface wind speed (WS) and significant wave height (SWH) measurements are monitored and validated against operational European Centre for Medium-Range Weather Forecasts (ECMWF) atmospheric and wave model results in addition to available in-situ observations to access their suitability for various applications, especially SWH data assimilation. The quality of SWH is very high while that of WS is very good except for an underestimation of high wind speeds. The impact of assimilating SWH in the ECMWF Integrated Forecast System was assessed using several numerical experiments. The results show positive impact. Operational assimilation of SWH at ECMWF model is part of the forthcoming model change. 相似文献
18.
再论台风波浪的波型及其与海岸工程设计波浪要素的关系 总被引：3，自引：0，他引：3
本文以实测台风波浪资料对台风影响过程中固定点波浪能量集中度的变化和有效波陡的变化进行分析，得出华南近岸浅水区台风波浪的波型与台风中心位置的统计关系，并进一步阐明了台风过程中固定点出现较大台风波浪的波型是风浪以及用于海岸工程设计的台风波浪亦为风浪的结论。文中还讨论了台风波浪波型对海岸工程建设中的设计波高、周期等要素取值的影响。 相似文献
19.
In this paper, the modified Bayesian method for the analysis of directional wave spectra and reflection coefficients is verified by numerical and physical simulation of waves. The results show that the method can basically separate the incident and reflected directional spectra. In addition, the effect of the type of wave gage arrays, the number of measured wave properties, and the distance between the wave gage array and the reflection line on the resolution of the method are investigated. Some suggestions are proposed for practical application. 相似文献
20.
Xu Shikai Wang Hongchuan Hong Guangwen
Engineer Nanjing Hydraulic Research Institute Nanjing .
Professor Research Institute of Coastal Ocean Engineering Hohai University Nanjing 《中国海洋工程》1996,(4)
To solve problems concerning wave elements and wave propagation, an effective way is the wave energy balance equation, which is widely applied in oceanography and ocean dynamics for its simple computation. The present papaer advances wave energy balance equations considering lateral energy transmission and energy loss as the governing equation for the study of wave refraction-diffraction. For the mathematical model, numerical simulation is made by means of difference method, and the result is verified with two examples. 相似文献