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Journal of Hydrodynamics 2011年第5期23卷 625-636页

作者： SHAN Tie-bing YANG Jian-min LI Xin XIAO Long-fei State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200240 China

This article mainly concentrates on a large-volume drilling semi-submersible platform, aiming to reveal wave run-up characteristics along square columns and give the relationship between air gap distributions and wave parameters. The tests with fixed model were conducted firstly on its encountering a series of monochromatic waves. A wide range of wave slope （H/L ） were selected to investigate the air gap response in detail. As can be seen, larger wave steepness will generally cause smaller air gap in the same wave period, which indicates nonlinear effects of incoming wave can amplify wave elevation. Model tests with mooring condition were also conducted in the same wave conditions. As was expected, the maximum relative wave elevation reduces obviously compared with the fixed one. However, wave shape close to columns show higher harmonic characteristics due to interaction between waves and the columns of semi-submersible platform. Meaningful conclusions from the model tests are drawn in this article, which is helpful in air gap design of floating offshore platform to a certain extent. In addition, the experimental results will provide an important reference for further research on validation and update of theoretical models of air gap.

关键词： wave run-up air gap diffraction-radiation effects wave steepness

Experimental Investigation of wave Load and run-up on the Composite Bucket Foundation Influenced by Regular waves

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Journal of Ocean University of China 2021年第2期20卷 271-284页

作者： YU Tongshun ZHAO Zishuai SHI Zhongyu XU Yu College of Engineering Ocean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Ocean Engineering Qingdao 266100China State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China

In the design of wind turbine foundations for offshore wind farms, the wave load and run-up slamming on the supporting structure are the quantities that need to be considered. Because of a special arc transition, the interaction between the wave field and the composite bucket foundation(CBF) becomes complicated. In this study, the hydrodynamic characteristics, including wave pressure, load, upwelling, and run-up, around the arc transition of a CBF influenced by regular waves are investigated through physical tests at Shandong Provincial Key Laboratory of Ocean Engineering, Ocean University of China. The distributions of the wave pressures and upwelling ratios around the CBF are described, and the relationship between the wave load and the wave parameters is discussed. New formulae based on the velocity stagnation head theory with linear wave theory and the second-order Stokes wave theory for wave kinematics are proposed to estimate the wave run-up. Moreover, the multiple regression method with nonlinear technology is employed to deduce an empirical formula for predicting run-up heights. Results show that the non-dimensional wave load increases with the increase in the values of the wave scattering parameter and relative wave height. The wave upwelling height is high in front of the CBF and has the lowest value at an angle of 135? with the incoming wave direction. The performance of the new formulae proposed in this study is compared using statistical indices to demonstrate that a good fit is obtained by the multiple regression method and the analytical model based on the velocity stagnation head theory is underdeveloped.

关键词： physical experiment composite bucket foundation wave load wave run-up regular waves

Impedance Analytical Method of wave run-up and Reflection from A Slotted-Wall Caisson Breakwater

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China Ocean Engineering 2010年第3期24卷 453-465页

作者：朱大同 Southeast Traffic Engineering Consultation and Supervision Co. Ltd.Southeast University River and Harbor Engineering Department Nanjing Hydraulic Research Institute

An impedance analytical method （IAM） is developed to study the interaction of plane water wave with a slotted-wall caisson breakwater. The non-linear boundary condition at the slotted-wall is expressed in terms of flow resistance. A set of algebraic expressions are obtained for free surface elevation inside and outside chamber, and reflection coefficient. The prediction of the reflection coefficients shows that the relative widths of the chamber inducing the minimum reflection coefficient for a slotted-wall caisson breakwater are in a range of 0.10～0.20, which are smaller than that （0.15～0.25） for a perforated-wall caisson breakwater. The reflection coefficients and free surface elevation obtained by the present model are compared with that of laboratory experiments carried out by previous researchers.

关键词： plane wave slotted-wall caisson wave reflection wave run-up impedance analytical method （IAM）

wave run-up on A Vertical Seawall Protected by An Offshore Submerged Barrier

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China Ocean Engineering 2009年第3期23卷 553-564页

作者：张景新刘桦 School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University

Submerged barriers are constructed in coastal zones for shoreline or harbor protection or to prevent the beach erosion. In the present study, the wave run-up on a vertical seawall protected by a submerged barrier is analyzed. The physical configurations include a rigid barrier and a long channel of finite depth. For linear water waves, by matching the velocity along the barrier and along the gap, the systems of linear equations about the velocity potentials are obtained. The wave rim-up is further analyzed for various settings of barrier height and distance between the barrier and the wall, i.e. the chamber length. For nonlinear waves and random sea waves, a numerical model is extended to investigate the effect parameters of the barrier on the wave rim-up against the seawall. Not only the numerical simulations, but also the analytical results illustrate that the wave run-up on the seawall depends very much on the distance between the barrier and the vertical seawall.

关键词： submerged barrier standing wave wave run-up

Experimental Study on 2-D Focusing wave run-up on A Vertical Cylinder

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China Ocean Engineering 2010年第3期24卷 499-512页

作者：柳淑学孙一艳李金宣臧军 State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Department of Architecture and Civil Engineering Science University of Bath

In this paper,the focused wave groups with different parameters and their actions on a vertical cylinder are experimentally studied. The harmonic wave characteristics of the focusing waves are analyzed by the addition and subtraction of the crest and trough focusing waves. The analyzed results show that higher order harmonics can be generated because of the interaction of component waves. Nonlinearity increases with the inputted wave amplitude and the frequency width increment. Further, the wave run-up around the vertical circular cylinder is experimentally studied. It increases with the wave steepness and the relative cylinder diameter increase. However, the variations of wave run-up around the circular cylinder are different. The researches provide a reference for further numerical studies.

关键词： wave focusing nonlinearity vertical circular cylinder wave run-up

Prediction on Irregular wave run-up and Overtopping

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China Ocean Engineering 2010年第3期24卷 481-498页

作者：陈国平严士常周益人 Key Laboratory of Coastal Disaster and Defence Ministry of EducationHohai University Nanjing Hydraulic Research Institute

A series of hydraulic model tests are carried out to investigate random wave run-up and overtopping on smooth, impermeable single slope and composite slope. Based on the analysis of the influences of wave steepness, structure slope, incident wave angle, width of the berm and water depth on the berm and the wave run-up, empirical formulas for wave run-up on dike are proposed. Moreover, empirical formula on estimating the wave run-up on composite slope with multiple berms is presented for practical application of complex dike cross-section. The present study shows that the influence factors for wave overtopping are almost the same as those for wave run-up and the trend of the wave overtopping variation with main influence parameters is also similar to that for wave run-up. The trend of the wave overtopping variations can be well described by two main factors, i.e. the wave run-up and the crest freeboard of the structure. A new prediction method for wave overtopping is proposed for random waves. The proposed prediction formulas are applied to case study of over forty cases and the results show that the prediction methods are good enough for practical design purposes.

关键词： wave run-up overtopping oblique wave composite slope

wave run-up on A Coaxial Perforated Circular Cylinder

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China Ocean Engineering 2011年第2期25卷 201-214页

作者：朱大同 Jiangsu Key Laboratory of Engineering Mechanics Southeast University River and Harbor Engineering Department Nanjing Hydraulic Research Institute

This paper describes a plane regular wave interaction with a combined cylinder which consists of a solid inner column and a coaxial perforated outer cylinder. The outer perforated surface is a thin porous cylinder with an annular gap between it and the inner cylinder. The non-linear boundary condition at the perforated wall is a prime focus in the study; energy dissipation at the perforated wall occurs through the resistance to the fluid across the perforated wall. Explicit analytical formulae are presented to calculate the wave run-up on the outer and inner surfaces of the perforated cylinder and the surface of the inner column. The theoretical results of the wave run-up are compared with previous experimental data. Numerical results have also been obtained： when the ratio of the annular gap between the two cylinders to incident wavelength （b-a）/L≤0. 1, the wave run-up on the inner surface of the perforated cylinder and the surface of inner column can partially or completely exceed the incident wave height.

关键词： plane water wave coaxial perforated cylinder wave run-up flow resistance

THE VOF METHOD FOR STUDY OF wave run-up AND BREAKING ON A SLOPING STRUCTURE

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Journal of Hydrodynamics 1997年第4期9卷 88-96页

作者： Wan De-chengShanghai Institute of Applied Mathematics, and Mechanics Shanghai University,Shanghai200072, P. R. China.Miao Guo-pingDepartment of Naval Architecture and Ocean Engineering, Shanghai Jiao Tong University,Shanghai 200030,P. R. China.Dai Shi-qiangShanghai Institute of Applied Mathematics and Mechanics, Shanghai University,Shanghai200072, P. R. China.

The volume of fluid method (VOF method) for numerical simulations describing wave run-up on a sloping structure including the overturning. breaking and merging phenomena is presented. The flow motions are governed by the classical, two-dimensional Navier-Stokes equation for incompressible fluid. Computational results concerning the time evolution of the free surface and pressure distribution along water bed and slope boundary are given, showing how an initial solitary wave undergoes run-up, overturning, breaking and merging on the slope. It is found that most of the wave energy is lost after the wave breaking and merging.

关键词： VOF method wave run-up wave breaking sloping structure

Benchmark experimental study on wave run-ups of fixed four-rounded-square-column array in regular waves

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Journal of Ocean Engineering and Science 2022年第5期7卷 419-430页

作者： Jing Liu Longfei Xiao Lijun Yang Jun Li Yufeng Kou State key laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai200240China SJTU-Sanya Yazhou Bay Institute of Deepsea Technology Hainan 572024China

wave run-up on surface-piercing columns is an important phenomenon in offshore engineering.Previous studies have mainly focused on a single column and circular column arrays.This study is concerned with the wave run-up ratio and the wave force on a fixed array of four rounded square columns.A series of regular wave tests were conducted,and the effects of wave periods and steepness were investigated.The nonlinearity of the wave run-up under incident waves with a small period is more sensitive to wave steepness.Utilizing empirical mode decomposition(EMD)and fast Fourier transform(FFT)methods,the measured signals were separated into three components representing characteristics of the incident wave component(IMF1),near-field interference(IMF2),and far-field low frequency reflected wave(IMF3),respectively.The proposed methods are helpful for studying the mechanism of near-field interference,and the experimental data are essential benchmarks for validating further numerical simulations of wave runups on rounded square columns.

关键词： wave run-up Square columns wave force Near-field interference

Comparative Experimental and Numerical Study of wave Loads on A Monopile Structure Using Different Turbulence Models

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China Ocean Engineering 2021年第4期35卷 554-565页

作者： ZENG Xin-meng SHI Wei Constantine MICHAILIDES WANG Kai LI Xin DeepWater Engineering Research Centre Dalian University of TechnologyDalian 116024China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China Civil Engineering and Geomatics Cyprus University of TechnologyLimassol 2026Cyprus School of Marine Engineering and Technology Sun Yat-Sen UniversityZhuhai 51900China

This study numerically and experimentally investigates the effects of wave loads on a monopile-type offshore wind turbine placed on a 1:25 slope at different water depths as well as the effect of choosing different turbulence models on the efficiency of the numerical model.The numerical model adopts a two-phase flow by solving Unsteady Reynolds-Averaged Navier−Stokes(URANS)equations using the Volume Of Fluid(VOF)method and three differentk-􀀀ωturbulence models.Typical environmental conditions from the East China Sea are studied.The wave run-up and the wave loads applied on the monopile are investigated and compared with relevant experimental data as well as with mathematical predictions based on relevant theories.The numerical model is well validated against the experimental data at model scale.The use of different turbulence models results in different predictions on the wave height but less differences on the wave period.The baseline k-􀀀ωturbulence model and Shear-Stress Transport(SST)k-􀀀ωturbulence model exhibit better performance on the prediction of hydrodynamic load,at a model-scale water depth of 0.42 m,while the laminar model provides better results for large water depths.The SST turbulence model performs better in predicting wave run-up for water depth 0.42 m,while the laminar model and standard k-􀀀ωmodel perform better at water depth 0.52 m and 0.62 m,respectively.

关键词： hydrodynamic loads turbulence models Morison equation wave run-up numerical wave tank monopile structure