海堤上波浪爬高与越浪计算分析     

王鹏  孙大鹏  吴浩 《海洋工程》2011,29(4):97-102

基于线性波理论,采用VOF法、RNG k-ε的湍流模型,通过FLUENT软件平台的二次开发功能实现了质量源造波。利用多孔介质模型,在动量方程里添加多孔介质源项,对斜坡堤上铺设异型块体时的爬高与越浪进行了数值模拟,并通过模拟爬高值率定出FLUENT中多孔阻力系数与多种异形块体糙渗系数之间的关系,进而建立了可供实际应用的海堤上波浪爬高与越浪数值模型。  相似文献   

Coastal ridge constructive processes at a multi-decadal scale in Barreta Island (southern Portugal)     

Xabier Herrero  Susana Costas  Katerina Kombiadou 《地球表面变化过程与地形》2020,45(2):411-423

Multiple ridges across prograding coasts may display variable geometries, commonly expressed through varying elevations. Changes in ridge elevation have been traditionally related to the occurrence of fluctuating progradation rates, which might, in turn, be driven by shifting environmental conditions. Here, we explore the geometry and growth mechanisms of multiple ridges, generated at Barreta Island (Ria Formosa, southern Portugal), as a consequence of the rapid progradation of the island over the last 70 years, following the artificial fixation of the downdrift Faro-Olhão inlet with jetties in 1955. The variability in the morphology of these features was analysed in combination with available wind and wave data, in order to better distinguish growth mechanisms and understand the main parameters determining the final geometry of the observed ridges. The results suggest that (1) most of the identified ridges fall in the beach ridge classification, as they have been mostly built by marine processes, and (2) the parameters derived from, or closely related to wave climate variability (e.g. progradation rates, storm occurrence) can jointly explain most of the observed morphological changes, while aeolian processes played a secondary role. Indeed, ridge geometry appears mainly controlled by progradation rates, with higher ridges associated with lower progradation rates. Progradation rate, in turn, is mostly related to longshore wave power, storminess, and the occurrence storm groups. Yet, the final configuration of ridges can also be affected by runup levels and onshore winds. Therefore, establishing the relation between ridge geometry and wave climate is not a straightforward task, because of the complex processes and interactions that control coastal morphodynamics. © 2019 John Wiley & Sons, Ltd.  相似文献   

Long Waves Associated with Bichromatic Waves   总被引：1，自引：0，他引：1  

DONG Guohai 《中国海洋工程》2001,(2):281-289

A numerical model of low frequency waves is presented. The model is based on that of Roelvink (1993), but the nu-merical techniques used in the solution are based on the so-called Weighted-Average Flux (WAF) method with Time-Operator-Splitting (TOS) used for the treatment of the source terms. This method allows a small number of computational points to be used, and is particularly efficient in modeling wave setup. The short wave (or primary wave) energy equation is solved with a traditional Lax-Wendroff technique. A nonlinear wave theory is introduced. The model described in this paper is found to be satisfactory in modeling low frequency waves associated with incident bichromalic waves.  相似文献   

Second order wave diffraction forces and runup by finite—infinite element method     

B.Y. Li  S.L. Lau  C.O. Ng 《Applied Ocean Research》1991,13(6):270-286

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Wave runup on a concentric twin perforated circular cylinder     

K. Vijayalakshmi  S. Neelamani  R. Sundaravadivelu  K. Murali 《Ocean Engineering》2007,34(2):327-336

The regular wave interaction with a twin concentric porous circular cylinder system consisting of an inner impermeable cylinder and an outer perforated cylinder was studied through physical model and numerical model studies. The experiments were carried out on the twin concentric cylinder model in a wave flume to study the wave runup and rundown at the leading and trailing edges of the perforated cylinder. It was found that the maximum wave runup on the perforated cylinder is almost same as the incident wave height. The experimental results were used to develop the predictive formulae for the wave runup and rundown on the perforated cylinder, which can be easily used for design applications. The wave runup profiles around the perforated cylinder for different values of ka and porosities were studied numerically using Green's Identity Method. The results of the numerical study are presented and compared with the experimental measurements.  相似文献   

浙江省海塘塘顶高程的确定   总被引：10，自引：1，他引：10  

黄世昌  周骥等 《海洋工程》2001,19(4):67-71

介绍了浙江省海塘塘顶高程确定时所涉及的波浪爬高，越浪量等的计量，同时分析了1997年后浙江省海塘塘顶高程确定的方法，由已建海塘的塘顶高程分析可见，在背水坡和塘顶有保护措施的情况下，采用允许最大越波流量来控制海塘塘顶高程，可适当降低塘身高度。  相似文献   

基于RDBMS的积件技术的应用研究     

李毅心 《成都信息工程学院学报》2006,21(2):206-209

积件技术是教学软件发展的方向，探讨了用Power Builder前台结合SQL Server关系数据库后台进行多媒体教学积件管理的应用模式，并结合具体教学示例，进行了分析说明。  相似文献   

非开挖导向钻进实际轨迹的控制设计   总被引：4，自引：0，他引：4  

张德龙  蒋荣庆 《吉林大学学报(地球科学版)》2003,33(2):246-248

非开挖导向钻进技术，具有施工速度快、适用范围广等优点，得到了广泛的应用。在实际钻进中，由于钻进在地下的不确定性，影响了导向钻进的顺利进行。到得钻进中当前点的顶角、方位角和孔深，通过均角全距法原理，可以近似地描绘出当前钻孔的空间实际轨迹，并确定钻头的位置。应用这一原理，同时运用VisualBasic语言和AutoCAD绘图工具相结合的方法，编制一套应用程序，可以直接绘制出当前钻孔轨迹，并可实现对钻孔轨迹的调控，从而保证导向钻进的顺利进行。  相似文献   

Field survey of the 1994 Mindoro Island,Philippines tsunami   总被引：2，自引：0，他引：2  

Fumihiko Imamura  Costas E. Synolakis  Edison Gica  Vasily Titov  Eddie Listanco  Ho Jun Lee 《Pure and Applied Geophysics》1995,144(3-4):875-890

This is a report of the field survey of the November 15, 1994 Mindoro Island, Philippines, tsunami generated by an earthquake (M=7.0) with a strike-slip motion. We will report runup heights from 54 locations on Luzon, Mindoro and other smaller islands in the Cape Verde passage between Mindoro and Luzon. Most of the damage was concentrated along the northern coast of Mindoro. Runup height distribution ranged 3–4 m at the most severely damaged areas and 2–4 in neighboring areas. The tsunami-affected area was limited to within 10 km of the epicenter. The largest recorded runup value of 7.3 m was measured on the southwestern coast of Baco Island while a runup of 6.1 m was detected on its northern coastline. The earthquake and tsunami killed 62 people, injured 248 and destroyed 800 houses. As observed in other recent tsunami disasters, most of the casualties were children. Nearly all eyewitnesses interviewed described the first wave as a leading-depression wave. Eyewitnesses reported that the main direction of tsunami propagation was SW in Subaang Bay, SE in Wawa and Calapan, NE on Baco Island and N on Verde Island, suggesting that the tsunami source area was in the southern Pass of Verde Island and that the wave propagated rapidly in all directions. The fault plane extended offshore to the N of Mindoro Island, with its rupture originating S of Verde Island and propagating almost directly south to the inland of Mindoro, thereby accounting for the relatively limited damage area observed on the N of Mindoro.  相似文献   

Modeling of the runup heights of the Hokkaido-Nansei-Oki tsunami of 12 July 1993     

Katsuyuki Abe 《Pure and Applied Geophysics》1995,144(3-4):735-745

The Hokkaido-Nansei-Oki earthquake (M _w 7.7) of July 12, 1993, is one of the largest tsunamigenic events in the Sea of Japan. The tsunami magnitudeM _t is determined to be 8.1 from the maximum amplitudes of the tsunami recorded on tide gauges. This value is larger thanM _w by 0.4 units. It is suggested that the tsunami potential of the Nansei-Oki earthquake is large forM _w . A number of tsunami runup data are accumulated for a total range of about 1000 km along the coast, and the data are averaged to obtain the local mean heightsH _n for 23 segments in intervals of about 40 km each. The geographic variation ofH _n is approximately explained in terms of the empirical relationship proposed byAbe (1989, 1993). The height prediction from the available earthquake magnitudes ranges from 5.0–8.4 m, which brackets the observed maximum ofH _n , 7.7 m, at Okushiri Island.  相似文献