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Theoretical & Applied Mechanics Letters 2021年第3期11卷 151-156页

作者： I.Magdalena N.Karima H.Q.Rif’atin Faculty of Mathematics and Natural Sciences Bandung Institute of TechnologyBandungIndonesia

seiches are long-period standing waves with a unique period called a natural resonant period,during which the phenomenon of resonance occurs.The occurrence of resonance in coastal areas can cause destruction to surrounding natural and man-made structures.By determining the resonant period of a given basin,we can pinpoint the conditions that allow waves to achieve resonance.In this study,a mathematical model is developed from the shallow water equations to examine seiches and resonances in various types of closed basin.The developed model is solved analytically using the separation of variables method to determine the seiches’fundamental resonant periods.Comparisons between the analytical solutions and experimental measurements for resonant periods are also provided.It is shown that the analytical resonant period confirms the experimental data for closed basin of various geometric profiles.Using a finite volume method on a staggered grid,the model is solved numerically to simulate the wave profile when resonance phenomenon occurs.Through those numerical simulations,we also obtain the fundamental resonant period for each basin which agrees with the derived analytical period.

关键词： seiches Fundamental resonant period Closed basin Shallow water equations Finite volume method

Numerical Investigations on Harbor Oscillations Induced by Falling Objects

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China Ocean Engineering 2023年第3期37卷 458-470页

作者： GAO Jun-liang BI Wen-jing ZHANG Jian ZANG Jun School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China Key Laboratory of Port Waterway and Sedimentation Engineering of MOTNanjing Hydraulic Research InstituteNanjing 210029China Key Laboratory of Water Security Guarantee in Guangdong-Hong Kong-Marco Greater Bay Area of Ministry of Water Resources Guangzhou 510611China Centre for Infrastructure Geotechnical and Water Engineering(IGWE)Department of Architecture and Civil EngineeringUniversity of BathBA27AYUK

In this paper,the open-sourced computational fluid dynamics software,OpenFOAM~?,is used to study the fluctuation phenomenon of the water body inside a horizontally one-dimensional enclosed harbor basin with constant water depth triggered by falling wedges with various horizontal falling positions,initial falling velocities and masses.Based on both Fourier transfo rm analysis and wavelet spectrum analysis for the time series of the free surface elevations inside the harbor basin,it is found for the first time that the wedge falling inside the harbor can directly trigger harbor resonance.The influences of the three factors(including the horizontal falling position,the initial falling velocity,and the mass)on the response amplitudes of the lowest three resonant modes are also investigated.The results show that when the wedge falls on one of the nodal points of a resonant mode,the mode would be remarkably suppressed.Conversely,when the wedge falls on one of the anti-nodal points of a resonant mode,the mode would be evidently triggered.The initial falling velocity of the wedge mainly has a remarkable effect on the response amplitude of the most significant mode,and the latter shows a gradual increase trend with the increase of the former.While for the other two less significant modes,their response amplitudes fluctuate around certain constant values as the initial falling velocity rises.In general,the response amplitudes of all the lowest three modes are shown to gradually increase with the mass of the wedge.

关键词： harbor oscillations seiches falling objects resonant mode response amplitude

Preliminary Research on the Characteristics and Causes of Formation of seiches in the Bays

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Marine Science Bulletin 2000年第1期2卷 88-94页

作者：吴少华王喜年戴明瑞 National Marine Environmental Forecast Center Beijing 100081

The Haizhou and Daya bays are chosen as basins for seiche research in this paper. By reducing the astronomical tide, we obtain residuals which include seiches from the original observed tide curve of two representative gauges of the Haizhou and Daya bays, with a time resolution of 1min. We have further made a statistical analysis of the characteristics of the seasonal distribution of seiches and by making a comparative analysis of the seiches and the corresponding weather system, studied the origin of seiches. The research findings are of important reference value for the ocean engineering design and the storm surge forecast.

关键词： seiches cause of formation spectral analysis Daya Bay Haizhou Bay seasonal variation

Theoretical Analysis of Harbor Resonance in Harbor with An Exponential Bottom Profile

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China Ocean Engineering 2015年第6期29卷 821-834页

作者：王岗郑金海梁秋华张蔚黄诚 State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University College of Harbor Coastal and Offshore Engineering Hohai University State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology School of Civil Engineering & Geosciences Newcastle University China Petroleum Pipeline Bureau No. 6 Construction Company

The general features of oscillations within a rectangular harbor of exponential bottom are investigated analytically. Based on the linear shallow water approximation, analytical solutions for longitudinal oscillations induced by the incident perpendicular wave are obtained by the method of matched asymptotics. The analytic results show that the resonant frequencies are shifted to larger values as the water depth increases and the oscillation amplitudes are enhanced due to the shoaling effect. Owing to the refraction effect, there could be several transverse oscillation modes existing in when the width of the harbor is on the order of the oscillation wavelength. These transverse oscillations are similar to standing edge waves, and there are m node lines in the longshore direction and n node lines running in the offshore direction corresponding to mode（n, m）. Furthermore, the transverse eigen frequency is not only related to the width of the harbor, but also to the boundary condition at the backwall and the bottom shape.

关键词： harbor resonance oscillations seiches long-waves shallow water equations

Tide variation and signals during 2000-2004 in the northern Gulf of Aqaba, Red Sea

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Natural Science 2013年第12期5卷 1264-1271页

作者： Riyad Manasrah Department of Coastal Environment Faculty of Marine Sciences The University of Jordan-Aqaba Aqaba Jordan

Variations of tide and mean sea level (MSL) were studied during the period August 2000-March 2004 in the northern Gulf of Aqaba to detect the seasonal differences of tide records and tide components signals. The study revealed seasonal cycle of the MSL in the northern Gulf, which was lower during summer than in winter due to the relative strong wind and higher evaporation during summer. The MSL during the year of 2003 Fwas the lowest comparing to the other years duing the study period which might be related to wind driven force and mixed layer depth. The statistical comparison analysis of the MSL among winters, springs and summers of the years 2000- 2004 exhibited significant difference values (p K1) and a lunar terdiurnal constituent (M3), respectively.

关键词： Sea Level seiches Semi-Enclosed Seas Gulf of Aqaba Red Sea