Статті в журналах: "Offshore structures – Hydrodynamics"

1

Faulkner, D. "Hydrodynamics of offshore structures." Marine Structures 1, no. 1 (January 1988): 81–83. http://dx.doi.org/10.1016/0951-8339(88)90012-3.

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2

Sarpkaya, T. "Offshore Hydrodynamics." Journal of Offshore Mechanics and Arctic Engineering 115, no. 1 (February 1, 1993): 2–5. http://dx.doi.org/10.1115/1.2920085.

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In this paper, we present several applied as well as fundamental research problems related to the future needs of the offshore engineering. The paper starts out with a detailed discussion of the current uncertainties and constraints. Then, specific research issues on environmental input conditions, on the role of computational fluid dynamics, and on damping and dynamic response are presented. It is suggested that an appreciation of the input parameters, acquisition of extensive data to properly characterize the ocean environment, development of new methods and tools to acquire relevant data, extensive use of the computational methods, basic/applied research on the dynamic response and damping of structures, use of new materials, science-and-technology transfer from sister disciplines (e.g., aerospace industry, keeping in mind the complexities brought about by the presence of the air-water interface), and other related research will significantly enhance our ability to design and build a variety of safer and economical offshore structures in deeper waters as well as over marginal fields in the next few decades. This herculean effort will require several decades of complementary experimental, numerical and analytical studies of ocean-structure interaction which will serve to elucidate the basic as well as applied fluid mechanics phenomena relevant to the offshore mechanics.

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3

Isaacson, Michael. "Wave and current forces on fixed offshore structures." Canadian Journal of Civil Engineering 15, no. 6 (December 1, 1988): 937–47. http://dx.doi.org/10.1139/l88-125.

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The Canadian Standards Association standard S471 "General requirements, design criteria, environment, and loads, Part 1 of the CSA code for the design, construction and installation of fixed offshore structures" contains an appendix "Wave and current loads." To compliment this appendix, the present paper provides a more detailed survey of this topic with a review of the recent literature and recommendations of hydrodynamic data needed in offshore design. In addition, hydrodynamic considerations in the calculation of earthquake and ice loads are mentioned. Key words: currents, current forces, hydrodynamics, ocean engineering, offshore structures, waves, wave forces.

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4

Faltinsen, O. M. "Hydrodynamics of marine and offshore structures." Journal of Hydrodynamics 26, no. 6 (December 2014): 835–47. http://dx.doi.org/10.1016/s1001-6058(14)60092-5.

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5

Tomasicchio, Giuseppe Roberto, Elvira Armenio, Felice D'Alessandro, Nuno Fonseca, Spyros A. Mavrakos, Valery Penchev, Holger Schuttrumpf, Spyridon Voutsinas, Jens Kirkegaard, and Palle M. Jensen. "DESIGN OF A 3D PHYSICAL AND NUMERICAL EXPERIMENT ON FLOATING OFF-SHORE WIND TURBINES." Coastal Engineering Proceedings 1, no. 33 (December 14, 2012): 67. http://dx.doi.org/10.9753/icce.v33.structures.67.

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The knowledge of the behavior of floating offshore wind turbines (W/T) under wave and/or wind action remains one of the most difficult challenges in offshore engineering which is mostly due to the highly non-linear response of the structure. The present study describes the design process of a 3D physical experiment to investigate the behavior of the most promising structure technology of floating W/T: spar buoy (SB) and tension leg platform (TLP) under different meteo conditions. In order to properly design the two W/T models, the following topics have been analyzed: mooring lines, mass distribution, appropriate scaling factor and data relative to the geometrical characteristics, wave basin dimensions and wind and waves conditions. In addition, the Smoothed Particle Hydrodynamics method (SPH) (Monaghan 1994) has been considered to simulate the 3D behavior of a floating offshore W/T. In particular, the SPH, calibrated and verified on the basis of the experimental observations, may represent a reliable tool for preliminary test of changes in the floater geometry.

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6

Tao, L., B. Molin, Y. M. Scolan, and K. Thiagarajan. "Spacing effects on hydrodynamics of heave plates on offshore structures." Journal of Fluids and Structures 23, no. 8 (November 2007): 1119–36. http://dx.doi.org/10.1016/j.jfluidstructs.2007.03.004.

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7

Isaacson, Michael, and John Baldwin. "Wave–current effects on large offshore structures." Canadian Journal of Civil Engineering 16, no. 4 (August 1, 1989): 543–51. http://dx.doi.org/10.1139/l89-084.

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The various effects that influence loads acting on a large offshore structure due to the combination of waves and currents are reviewed. These may be broadly associated with potential flow effects and viscous effects. The potential flow effects are nonlinear and may generally be investigated by perturbation or time-stepping methods. Viscous effects include the onset of flow separation, which affects the validity of the assumed potential flow, as well as steady and oscillatory forces. The fluid mechanics of the complete wave–current–structure interaction problem are not yet well understood and areas in need of additional research are identified. Key words: currents, drag, drift forces, hydrodynamics, ocean engineering, offshore structures, waves, wave forces.

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8

Benitz, M. A., M. A. Lackner, and D. P. Schmidt. "Hydrodynamics of offshore structures with specific focus on wind energy applications." Renewable and Sustainable Energy Reviews 44 (April 2015): 692–716. http://dx.doi.org/10.1016/j.rser.2015.01.021.

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9

Isaacson, Michael de St Q. "Recent advances in the computation of nonlinear wave effects on offshore structures." Canadian Journal of Civil Engineering 12, no. 3 (September 1, 1985): 439–53. http://dx.doi.org/10.1139/l85-052.

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The present paper provides a review of recent research on various nonlinearities that arise in ocean wave interactions with offshore structures. These include nonlinearities associated with the incident waves alone, the response of slender structural members to waves, and the nonlinear diffraction problem involving wave interactions with large structures. Emphasis is given to areas of current research into two particular nonlinear problems. One concerns an investigation into alternative approximations to the Morison equation for flexible structures and the other concerns the numerical simulation of nonlinear wave diffraction around large structures. Key words: diffraction, hydrodynamics, nonlinear flow, ocean engineering, offshore structures, waves.

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10

Foschi, Ricardo, Michael Isaacson, Norman Allyn, and Steven Yee. "Combined wave – iceberg loading on offshore structures." Canadian Journal of Civil Engineering 23, no. 5 (October 1, 1996): 1099–110. http://dx.doi.org/10.1139/l96-917.

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The Canadian Standards Association has developed and published a code for the design and construction of fixed offshore structures. This code has been subjected to a comprehensive verification process which has identified several issues warranting further study. One of these relates to the combined effects of wave and iceberg collision loading. At present, this combination is treated by the use of a load combination factor specified in the Code. The present paper describes a recent study which was undertaken to determine the appropriateness of the recommended value of the load combination factor. The study involves a numerical analysis in which loads due to waves alone, an iceberg alone, and an iceberg and waves in combination have been calculated for a range of iceberg and wave parameters. These results have been applied to a first-order reliability analysis in order to study the force levels corresponding to an annual probability of 10−4 or to the onset of global sliding with an annual probability of 10−4. The paper thereby makes recommendations for load combination factors applicable to combined wave–iceberg loading. Key words: hydrodynamics, icebergs, ocean engineering, offshore structures, wave forces, waves.

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11

Isaacson, Michael, and Kevin McTaggart. "Influence of hydrodynamic effects on iceberg collisions." Canadian Journal of Civil Engineering 17, no. 3 (June 1, 1990): 329–37. http://dx.doi.org/10.1139/l90-040.

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This paper examines various hydrodynamic effects which should be considered when analyzing iceberg collisions with a fixed structure. Iceberg added mass is among the hydrodynamic parameters that must be known to evaluate collision severity. Effective added mass is shown to vary with collision duration and recommendations are made for the selection of added masses to be used in iceberg collision design. Iceberg impact velocities are influenced by waves and currents, which can both be significantly influenced by the presence of a large structure. Wave-driven iceberg drift motions are shown to be more sensitive than current-driven motions to the presence of a structure. The contribution of wave-induced oscillatory motions to impact velocity is also discussed. Key words: added mass, hydrodynamics, ice impact, icebergs, ocean engineering, offshore structures.

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12

Schulz, Karl W., and Yannis Kallinderis. "Numerical Prediction of the Hydrodynamic Loads and Vortex-Induced Vibrations of Offshore Structures." Journal of Offshore Mechanics and Arctic Engineering 122, no. 4 (June 22, 2000): 289–93. http://dx.doi.org/10.1115/1.1315302.

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An incompressible Navier-Stokes flow algorithm is coupled with an elastic body structural response to numerically investigate the hydrodynamics of several relevant offshore applications. These applications include the effects of surface roughness on a bare cylinder and the study of vortex-induced vibrations (VIV) for a cylinder at high Reynolds numbers. The Reynolds number for the roughness cases was Re=4×106, while the Reynolds number for the VIV cases ranged from 2.25×105⩽Re⩽4.75×105. Additional VIV cases were also performed for two common suppression devices: strakes and fairings. The results from both the roughness and bare cylinder VIV applications were compared to experimental data in order to further validate the numerical scheme and illustrate the effectiveness of applying Navier-Stokes technologies to offshore applications. [S0892-7219(00)00604-X]

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13

Dao, M. H., H. Xu, E. S. Chan, and P. Tkalich. "Numerical modelling of extreme waves by Smoothed Particle Hydrodynamics." Natural Hazards and Earth System Sciences 11, no. 2 (February 11, 2011): 419–29. http://dx.doi.org/10.5194/nhess-11-419-2011.

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Abstract. The impact of extreme/rogue waves can lead to serious damage of vessels as well as marine and coastal structures. Such extreme waves in deep water are characterized by steep wave fronts and an energetic wave crest. The process of wave breaking is highly complex and, apart from the general knowledge that impact loadings are highly impulsive, the dynamics of the breaking and impact are still poorly understood. Using an advanced numerical method, the Smoothed Particle Hydrodynamics enhanced with parallel computing is able to reproduce well the extreme waves and their breaking process. Once the waves and their breaking process are modelled successfully, the dynamics of the breaking and the characteristics of their impact on offshore structures could be studied. The computational methodology and numerical results are presented in this paper.

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14

Isaacson, Michael, Thomas Mathai, and Carol Mihelcic. "Hydrodynamic coefficients of a vertical circular cylinder." Canadian Journal of Civil Engineering 17, no. 3 (June 1, 1990): 302–10. http://dx.doi.org/10.1139/l90-037.

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The added mass and the damping coefficient of a large surface-piercing circular cylinder extending to the seabed and undergoing horizontal oscillations are described. A closed-form solution to the corresponding linear radiation problem is obtained by the use of eigenfunction expansions. Attention is given to the vertical distribution of these coefficients and to their high-frequency asymptotic behaviour. Comparisons are made with experimental measurements. The application to typical offshore structures is discussed. Key words: added mass, cylinders, damping, hydrodynamics, ocean engineering.

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15

Filipot, J. F., P. Guimaraes, F. Leckler, J. Hortsmann, R. Carrasco, E. Leroy, N. Fady, et al. "La Jument lighthouse: a real-scale laboratory for the study of giant waves and their loading on marine structures." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 377, no. 2155 (August 19, 2019): 20190008. http://dx.doi.org/10.1098/rsta.2019.0008.

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This paper presents results from an experiment designed to improve the understanding of the relationship between extreme breaking waves and their mechanical loading on heritage offshore lighthouses. The experiment, conducted at La Jument, an iconic French offshore lighthouse, featured several records of wave, current and structure accelerations acquired during severe storm conditions, with individual waves as high as 24 m. Data analysis focuses on a storm event marked by a strong peak in the horizontal accelerations measured inside La Jument. Thanks to stereo-video wave measurements synchronized to the acceleration record we were able to identify and describe the breaking wave responsible for this intense loading. Our observations suggest that this giant wave (19 m high) had a crest elevation high enough to directly hit the lighthouse tower, above the substructure. This paper reveals the potential for conducting ambitious field experiments from offshore lighthouses in order to collect valuable storm waves and wave loading observations. This offers a possible second service life for these heritage structures as in situ laboratories dedicated to the study of the coastal hydrodynamics and its interaction with marine structures. This article is part of the theme issue ‘Environmental loading of heritage structures’.

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16

Nielsen, Jan K., S. Helama, D. Rodland, and Jasper K. Nielsen. "Eemian marine mollusks and barnacles from Ristinge Klint, Denmark: hydrodynamics and oxygen deficiency." Netherlands Journal of Geosciences - Geologie en Mijnbouw 86, no. 2 (July 2007): 95–115. http://dx.doi.org/10.1017/s0016774600023118.

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AbstractTaphonomic analysis of Eemian marine mollusks and barnacles at Ristinge Klint on the island of Langeland (Denmark) provides a distinct record of a temporal succession in preservation states. Four different states of preservation are recognized and related to a decreasing hydrodynamic regime in the depositional setting of the Eemian Baltic Sea. The states show a deepening-upward transition from shallow bay environment towards deeper offshore environment. The depositional setting changed significantly in hydrodynamics about 620 and 1550 years into the Eemian (130,000 to 115,000 years BP), according to biostratigraphic correlation with the varves of the Bispingen succession. The taxonomic composition of the paleofauna supports such a deepening-upward interpretation with a contemporaneous change from brackish water to nearly full marine conditions. The sea bottom was affected by at least one period of oxygen deficiency. The analysis also shows that the preservation of shells varies according to differences in shell structures and life habits. Here we show how these differences should be considered in paleoenvironmental reconstructions based on taphonomic analyses. Taphonomy may play an important role in understanding the hydrodynamic conditions within the Eemian Baltic Sea.

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17

Isaacson, Michael, Norman Allyn, and Gary Loverich. "Development of a net pen system for aquaculture farming." Canadian Journal of Civil Engineering 20, no. 2 (April 1, 1993): 189–200. http://dx.doi.org/10.1139/l93-024.

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The present paper describes a study carried out to verify a new net pen system which has been developed for aquaculture farming at exposed coastal sites. The structure is based on the use of spar buoys rather than rigid floats to support the net. A prototype structure has been deployed in Juan de Fuca Strait, and a verification of the system is described. This has involved an assessment of the environmental conditions and hydrodynamic loading for the structure, strength and fatigue analyses, and a calibration of wave conditions and mooring line forces with respect to prototype measurements. Overall, the system has been found to perform very well. Recommendations are made for monitoring the prototype system and for carrying out a refined verification of the system based on additional data. Key words: aquaculture, fish farms, hydrodynamics, ocean engineering, offshore structures, waves, wave forces.

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18

Paik, Jeom Kee. "Toward Limit State Design of Ships and Offshore Structures Under Impact Pressure Actions: A State-of-the-Art Review." Marine Technology and SNAME News 43, no. 03 (July 1, 2006): 135–45. http://dx.doi.org/10.5957/mt1.2006.43.3.135.

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In design of ships and ship-shaped offshore units, issues related to impact pressure actions arising from sloshing, slamming, green water, or explosion are of particular concern. The structural response under impact pressure actions is quite different from that under static or quasistatic actions. It has been recognized that the limit state approach is a more rational basis for structural design and safety assessment where both "demand" (loads) and "capacity" (strength) must be accurately defined. For impact pressure action cases, the demand is associated with hydrodynamics areas, taking into account the characteristics of impact pressure-time history, and the structural capacity is associated with structural mechanics areas, considering geometric and material nonlinearities together with strain rate sensitivity. This paper reviews recent advances and trends toward future limit state design of ships and offshore structures under impact pressure actions.

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19

Nakajima, K., Y. Kallinderis, I. Sibetheros, R. W. Miksad, and K. Lambrakos. "A Numerical Study of the Hydrodynamics of Reversing Flows Around a Cylinder." Journal of Offshore Mechanics and Arctic Engineering 116, no. 4 (November 1, 1994): 202–8. http://dx.doi.org/10.1115/1.2920152.

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A numerical study of the nonlinear and random behavior of flow-induced forces on offshore structures and experimental verification of the results are presented. The numerical study is based on a finite-element method for the unsteady incompressible Navier-Stokes equations in two dimensions. The momentum equations combined with a pressure correction equation are solved employing fourth-order artificial dissipation with a nonstaggered grid, instead of the more commonly used staggered meshes. The solution is advanced in time with a combined explicit and implicit marching scheme. Emphasis is placed on study of reversing flows around a cylinder. Comparisons with experimental data evaluate accuracy and robustness of the method.

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20

Roddier, Dominique, and Joshua Weinstein. "Floating Wind Turbines." Mechanical Engineering 132, no. 04 (April 1, 2010): 28–32. http://dx.doi.org/10.1115/1.2010-apr-2.

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This article discusses the functioning of floating wind turbines. The engineering requirements for the design of floating offshore wind turbines are extensive. Wind turbine design tools usually consist of an aerodynamic model (for flow around the blades) coupled with a structural code. Aero-elastic models used in the design of fixed turbines calculate all the necessary loading parameters, from turbine thrust and power generation, to blade and tower deflections. The design of floating structures usually involves hydrodynamics tools such as WAMIT Inc.’s software for studying wave interactions with vessels and platforms, or Principia’s DIODORE, to predict the hydrodynamic quantities, such as added mass, damping and wave exciting forces, which are used as a kernel in the time domain simulations. In marine projects, design tools typically need to be validated against model tests in a wave tank or basin. Such work is performed frequently, and scaling laws are very well defined.

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21

Isaacson, Michael, and Kwok Fai Cheung. "Influence of added mass on ice impacts." Canadian Journal of Civil Engineering 15, no. 4 (August 1, 1988): 698–708. http://dx.doi.org/10.1139/l88-090.

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The present paper applies potential theory to describe the variation of the added mass of an iceberg and its coupling effects on an offshore structure for various separation distances up to the point of contact. The strengths and weaknesses of the proposed model are discussed together with its practical application in ice mass impact problems. An impact model based on dynamic analysis is developed to calculate the impact force and response of a structure for head-on collisions. Both the contact-point added mass estimated in the present study and the traditionally assumed far-field added mass are used in the impact model separately. The results are compared and the crucial roles played by the ambient fluid during impact are discussed. Key words: added mass, hydrodynamics, ice impact, ocean engineering, offshore structures.

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22

Huan, Vo Nguyen Phu, Indra Sati H. Harahap, and Wesam Salah Alaloul. "Modelling of Tsunami Due to Submarine Landslide by Smoothed Particle Hydrodynamics Method." MATEC Web of Conferences 203 (2018): 01001. http://dx.doi.org/10.1051/matecconf/201820301001.

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Submarine landslide is the most serious threat on both local and regional scales. By way of addition to destroying directly offshore structures, slope failures may also generate destructive tsunami waves. This study has developed a numerical model based on the Smoothed Particle Hydrodynamics (SPH) method to predict four stages of generation, propagation, run-up, and impact of tsunami phenomenon. The numerical predictions in the research were validated with results in the literature and experimental tests. The results of the physical and numerical results presented in this study effort to develop these rule of thumbs to clearly understand some of the mechanics that may play a role in the assessment of tsunami waves.

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23

Isaacson, Michael, and Kwok Fai Cheung. "Correction factors for nonlinear runup and wave forces on a large cylinder." Canadian Journal of Civil Engineering 21, no. 5 (October 1, 1994): 762–69. http://dx.doi.org/10.1139/l94-082.

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A recently developed numerical method for second-order wave diffraction is summarized and is used to develop a simplified approach to predicting nonlinear runup and maximum wave loads for large coastal and offshore structures subjected to regular waves. The perturbation method on which the method is based is extended to provide correction factors for the runup and maximum loads. These correction factors apply directly to the predictions of linear diffraction theory, and are independent of the wave height. The correction factors for runup, maximum force and maximum overturning moment are provided for a range of geometric parameters relating to the case of a large circular cylinder extending from the seabed to the free surface. Nonlinear runup and load maxima calculated by the correction factors are compared with the results of previous experimental studies; in general, favourable agreement is obtained. An example application of the proposed procedure is provided, the importance of nonlinear effects in the evaluation of runup and wave loads is discussed, and the limitations of the results are indicated. Key words: coastal structures, diffraction, hydrodynamics, ocean engineering, offshore structures, wave runup, wave force, waves.

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24

Li, Qian, Yu Cao, Boyang Li, David M. Ingram, and Aristides Kiprakis. "Numerical Modelling and Experimental Testing of the Hydrodynamic Characteristics for an Open-Frame Remotely Operated Vehicle." Journal of Marine Science and Engineering 8, no. 9 (September 7, 2020): 688. http://dx.doi.org/10.3390/jmse8090688.

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The remotely operated vehicles (ROVs) are important to provide the technology support for both the traditional offshore structures and rapidly-growing renewable energy facilities during their full-lifecycles, such as site survey, installation, inspection, maintenance and repair. Regarding the motion and performance of a ROV, the understanding of its hydrodynamic properties is essential when exposing to the disturbances of wave and current. In this study, a numerical model is proposed within the frame of an open-source platform OpenFOAM. The hydrodynamics of the adopted ROV (BlueRov2) in its four principal degrees of freedoms (DOFs) is numerically simulated by a Reynolds-Averaged Navier-Stokes (RANS) solver. Meanwhile, an experimental test is carried out by using a novel technique on measuring the hydrodynamic forces and moments. To validate the numerical prediction methodologies, a set of systematic simulations of the ROV subjected to the disturbances caused by various flow conditions are performed. Comparing to the model test measurement, the numerical model proved to be reliable in offering a good estimation of the hydrodynamic parameters. This also indicates that the presented numerical methodologies and experimental techniques can be applied to other types of open-frame ROVs in quantifying the hydrodynamic parameters, capturing the physics of the fluid-structure interaction (FSI) and feature of the turbulent vorticity which are all essential for the effective control of the ROVs under the nonlinear flow disturbances.

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25

Yang, Yilin, and Jinzhao Li. "SPH-FE-Based Numerical Simulation on Dynamic Characteristics of Structure under Water Waves." Journal of Marine Science and Engineering 8, no. 9 (August 20, 2020): 630. http://dx.doi.org/10.3390/jmse8090630.

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Offshore structures are prone to produce a dynamic response under the effect of large wave load. In this paper, the smoothed particle hydrodynamics coupled with finite element (SPH-FE) method is used to investigate the dynamic characteristics of structure induced by the water waves. The dam break model is assumed to generate water wave. Firstly, the parameter of particle spacing included in the SPH method is examined and the appropriate value is proposed. Subsequently, the present numerical model is validated by comparing with the available results from the literature. Furthermore, the influence of several parameters on the wave load of the structure and the induced dynamic characteristics is studied, including the water column height, the distance between the water column and structure, and the structure stiffness. The results show that the amplification of the wave load on the bottom of structure is greater than that on the upper part of the structure. The increase of structure stiffness results in a decrease in the displacement at the top of structure, but an increase in the hydrodynamic force at the bottom of structure.

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26

He, Jiayi, Huiyu Wu, Ren-Chuan Zhu, Chen-Jun Yang, and Francis Noblesse. "Practical flow-representations for arbitrary singularity-distributions in ship and offshore hydrodynamics, with applications to steady ship waves and wave diffraction-radiation by offshore structures." European Journal of Mechanics - B/Fluids 83 (September 2020): 24–41. http://dx.doi.org/10.1016/j.euromechflu.2020.04.001.

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27

Isaacson, Michael, and Qi-Hua Zuo. "Nonlinear wave forces on a circular cylinder." Canadian Journal of Civil Engineering 16, no. 2 (April 1, 1989): 182–87. http://dx.doi.org/10.1139/l89-033.

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Nonlinear wave forces on a surface-piercing vertical circular cylinder are considered using a time-stepping method previously developed which is based on Green's theorem. Possible improvements in the efficiency, accuracy, and stability of the method are considered. Results based on this method are compared with those obtained previously using perturbation methods as well as with experimental results. It is found that the time-stepping method adopted here is quite reasonable. Wave force coefficients are given as functions of the governing parameters of the problem and the importance of nonlinear wave effects on the forces is assessed. Key words: hydrodynamics, ocean engineering, offshore structures, waves, wave forces.

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28

Huan, Vo Nguyen Phu, and Indra Sati Hamonangan Harahap. "Simulation of Tsunami Wave Generated by Submarine Slide: Generation, Propagation, Run-Up and Impact." Applied Mechanics and Materials 752-753 (April 2015): 1269–74. http://dx.doi.org/10.4028/www.scientific.net/amm.752-753.1269.

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Submarine slides can trigger tsunamis with high affecting offshore structures, subsea facilities and human lives along the shoreline. Unfortunately, slide-generated tsunami is a difficult problem due to the source of sliding of mass failure by itself or by the other earthquakes. There are no effective numerical model that could simulate simultaneously all stages of generation, propagation, run-up and impact of tsunami phenomena. Physical understanding of slide tsunami hazards is very poor. We must understand substance of tsunami clearly and how to find methods to reduce damage from tsunami wave. This paper will present a parallel computing based on ParallelSPHysics, it can simulate a comprehensive model of tsunami wave by using Smooth Particle Hydrodynamics method.

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29

Isaacson, Michael, and Thomas Mathai. "High frequency hydrodynamic coefficients of vertical cylinders." Canadian Journal of Civil Engineering 19, no. 4 (August 1, 1992): 606–15. http://dx.doi.org/10.1139/l92-070.

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Alternative methods of calculating high frequency added masses and damping coefficients of vertical cylinders of arbitrary section are described. Damping coefficients are calculated by a short-wave approximation relating to the local form of waves generated by the oscillating structure. As an alternative, they are also obtained from the exciting forces of the related scattering problem, with these forces obtained by a geometrical optics approximation. Added masses are obtained by discarding the propagating mode and using only the evanescent modes which are free of irregular frequencies. They are also obtained by an application of the Kramers–Kronig relations, which require the infinite frequency added masses and the damping coefficients at all frequencies. Numerical results obtained by the various methods are compared with corresponding analytical results for vertical circular and elliptic cylinders. The practical application of the proposed approach is indicated. Key words: added mass, cylinders, damping, hydrodynamics, ocean engineering, offshore structures, waves.

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30

McKiver, W. J., G. Sannino, F. Braga, and D. Bellafiore. "Investigation of model capability in capturing vertical hydrodynamic coastal processes: a case study in the north Adriatic Sea." Ocean Science 12, no. 1 (January 15, 2016): 51–69. http://dx.doi.org/10.5194/os-12-51-2016.

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Abstract. In this work we consider a numerical study of hydrodynamics in the coastal zone using two different models, SHYFEM (shallow water hydrodynamic finite element model) and MITgcm (Massachusetts Institute of Technology general circulation model), to assess their capability to capture the main processes. We focus on the north Adriatic Sea during a strong dense water event that occurred at the beginning of 2012. This serves as an interesting test case to examine both the models strengths and weaknesses, while giving an opportunity to understand how these events affect coastal processes, like upwelling and downwelling, and how they interact with estuarine dynamics. Using the models we examine the impact of setup, surface and lateral boundary treatment, resolution and mixing schemes, as well as assessing the importance of nonhydrostatic dynamics in coastal processes. Both models are able to capture the dense water event, though each displays biases in different regions. The models show large differences in the reproduction of surface patterns, identifying the choice of suitable bulk formulas as a central point for the correct simulation of the thermohaline structure of the coastal zone. Moreover, the different approaches in treating lateral freshwater sources affect the vertical coastal stratification. The results indicate the importance of having high horizontal resolution in the coastal zone, specifically in close proximity to river inputs, in order to reproduce the effect of the complex coastal morphology on the hydrodynamics. A lower resolution offshore is acceptable for the reproduction of the dense water event, even if specific vortical structures are missed. Finally, it is found that nonhydrostatic processes are of little importance for the reproduction of dense water formation in the shelf of the north Adriatic Sea.

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31

Chemisky, Bertrand, Fabio Menna, Erica Nocerino, and Pierre Drap. "Underwater Survey for Oil and Gas Industry: A Review of Close Range Optical Methods." Remote Sensing 13, no. 14 (July 15, 2021): 2789. http://dx.doi.org/10.3390/rs13142789.

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In both the industrial and scientific fields, the need for very high-resolution cartographic data is constantly increasing. With the aging of offshore subsea assets, it is very important to plan and maintain the longevity of structures, equipment, and systems. Inspection, maintenance, and repair (IMR) of subsea structures are key components of an overall integrity management system that aims to reduce the risk of failure and extend the life of installations. The acquisition of very detailed data during the inspection phase is a technological challenge, especially since offshore installations are sometimes deployed in extreme conditions (e.g., depth, hydrodynamics, visibility). After a review of high resolution mapping techniques for underwater environment, this article will focus on optical sensors that can satisfy the requirements of the offshore industry by assessing their relevance and degree of maturity. These requirements concern the resolution and accuracy but also cost, ease of implementation, and qualification. With the evolution of embedded computing resources, in-vehicle optical survey solutions are becoming increasingly important in the landscape of large-scale mapping solutions and more and more off-the-shelf systems are now available. The issues raised in this review are mainly related to the qualification of the results produced by optical systems and their limitations to cover all the needs expressed by the oil and gas industry field. Interesting qualification works of these solutions are presented in this paper as well as the use of online processing tools such as visual odometry or VSLAM to guide the data acquisition and pre-qualified survey. Finally, it seems interesting to combine acoustic and optical technologies in order to extend the field of application of these methods to low visibility conditions, which remains one of the main limiting factors in the generalization of the use of optical sensors in high resolution underwater cartography applications.

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32

Renilson, M., J. E. Soholt, and G. Macfarlane. "RECENT DEVELOPMENTS IN OCEAN ENGINEERING EDUCATION." APPEA Journal 41, no. 1 (2001): 783. http://dx.doi.org/10.1071/aj00047.

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Ocean engineering is a broad branch of engineering covering all aspects of engineering associated with the design, construction and operation of fixed and floating structures in the marine environment. It differs from naval architecture which traditionally focusses on ships and related ocean vehicles, and is of relevance to engineers in the offshore oil and gas industry.The Australian Maritime College (AMC) commenced running Australia’s first Bachelor of Engineering (Ocean Engineering) degree in 1997, with the first students graduating in 2000. The program was designed to meet the growing need of the Australian offshore oil and gas industry for graduate engineers skilled in the analysis and design of structures and facilities capable of operating in ever-increasing water depths. It builds on the already successful naval architecture degree offered by AMC, and has the first year completely in common.AMC makes use of its uniquely maritime focus and its wide variety of specialist facilities to produce graduates with a strong hands-on approach to complement their theoretical studies. The program features a unique blend of traditional marine and ocean-related subjects with a thorough grounding in hydrodynamics, wave theories, reservoir engineering, drilling technology, well design, offshore operations, oil and gas production technology and sub-sea engineering. As such, it is believed that the syllabus has a composition that is basically unique in the world.To support this new degree, AMC has commissioned the construction of a new Model Test Basin to complement its existing towing tank. This will have a plan form of 35 x 12 m and will be equipped with multi-directional wavemakers, making it ideal for student use, as well as consulting and staff research.The aim of the program is to produce engineering graduates with a broad theoretical background and a practical approach to problem solving. The ocean engineering graduates from AMC will be exceptionally well equipped to pursue successful careers within the international oil and gas industry.This paper describes briefly the various subjects that are unique to the ocean engineering degree and shows how the subject syllabi come together into a coherent program which will produce systems engineers rather than specialists. The course has just recently received Full Accreditation from The Institution of Engineers, Australia (IEAust).

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33

Kümmerer, Vincent, Teresa Drago, Cristina Veiga-Pires, Pedro F. Silva, Vitor Magalhães, Anxo Mena, Ana Lopes, et al. "Exploring Offshore Sediment Evidence of the 1755 CE Tsunami (Faro, Portugal): Implications for the Study of Outer Shelf Tsunami Deposits." Minerals 10, no. 9 (August 19, 2020): 731. http://dx.doi.org/10.3390/min10090731.

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Outer shelf sedimentary records are promising for determining the recurrence intervals of tsunamis. However, compared to onshore deposits, offshore deposits are more difficult to access, and so far, studies of outer shelf tsunami deposits are scarce. Here, an example of studying these deposits is presented to infer implications for tsunami-related signatures in similar environments and potentially contribute to pre-historic tsunami event detections. A multidisciplinary approach was performed to detect the sedimentary imprints left by the 1755 CE tsunami in two cores, located in the southern Portuguese continental shelf at water depths of 58 and 91 m. Age models based on 14C and 210Pbxs allowed a probable correspondence with the 1755 CE tsunami event. A multi-proxy approach, including sand composition, grain-size, inorganic geochemistry, magnetic susceptibility, and microtextural features on quartz grain surfaces, yielded evidence for a tsunami depositional signature, although only a subtle terrestrial signal is present. A low contribution of terrestrial material to outer shelf tsunami deposits calls for methodologies that reveal sedimentary structures linked to tsunami event hydrodynamics. Finally, a change in general sedimentation after the tsunami event might have influenced the signature of the 1755 CE tsunami in the outer shelf environment.

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34

Scandura, Pietro, Carla Faraci, and Enrico Foti. "A numerical investigation of acceleration-skewed oscillatory flows." Journal of Fluid Mechanics 808 (November 4, 2016): 576–613. http://dx.doi.org/10.1017/jfm.2016.641.

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Numerical simulations of wall-bounded acceleration-skewed oscillatory flows are here presented. The relevance of this type of boundary layer arises in connection with coastal hydrodynamics and sediment transport, as it is generated at the bottom of sea waves in shallow water. Because of the acceleration skewness, the bed shear stress during the onshore half-cycle is larger than in the offshore half-cycle. The asymmetry in the bed shear stress increases with increasing acceleration skewness, while an increase of the Reynolds number from the laminar regime causes the asymmetry first to decrease and then increase. Low- and high-speed streaks of fluid elongated in the streamwise direction emerge near the wall, shortly after the beginning of each half-cycle, at a phase that depends on the flow parameters. Such flow structures strengthen during the first part of the accelerating phase, without causing a significant deviation of the streamwise wall shear stress from the laminar values. Before the occurrence of the peak of the free stream velocity, the low-speed streaks break down into small turbulent structures causing a large increase in wall shear stress. The ratio of the root-mean-square (r.m.s.) of the fluctuations to the mean value (relative intensity) of the wall shear stress is approximately 0.4 throughout a relatively wide interval of the flow cycle that begins when breaking down of the streaks has occurred in the entire fluid domain. The acceleration skewness and the Reynolds number determine the phase at which this time interval begins. Both the skewness and the flatness coefficients of the streamwise wall shear stress are large when elongated streaks are present, while values of approximately 1.1 and 5.4 respectively occur just after breaking has occurred. The trend of both the relative intensity and the flatness of the spanwise wall shear stress are qualitatively similar to those of the wall shear in the streamwise direction. As a result of the acceleration skewness, the period-averaged Reynolds stress does not vanish. Consequently, an offshore directed steady streaming is generated which persists into the irrotational region.

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35

Bouvier, Clément, Bruno Castelle, and Yann Balouin. "Modeling the Impact of the Implementation of a Submerged Structure on Surf Zone Sandbar Dynamics." Journal of Marine Science and Engineering 7, no. 4 (April 25, 2019): 117. http://dx.doi.org/10.3390/jmse7040117.

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Coastal defense strategies based on structures are increasingly unpopular as they are costly, leave lasting scars on the landscape, and sometimes have limited effectiveness or even adverse impacts. While a clear improvement concerning aesthetic considerations using soft submerged breakwater is undeniable, their design has often focused on wave transmission processes across the crest of the structure, overlooking short- to medium-term morphodynamic responses. In this study, we used a time- and depth-averaged morphodynamic model to investigate the impact of the implementation of a submerged breakwater on surf zone sandbar dynamics at the beach of Sète, SE France. The hydrodynamic module was calibrated with data collected during a field experiment using three current profilers deployed to capture rip-cell circulation at the edge of the structure. The model showed good agreement with measurements, particularly for the longshore component of the flow (RMSE = 0.07 m/s). Results showed that alongshore differential wave breaking at the edge of the submerged breakwater drove an intense (0.4 m/s) two-dimensional circulation for low- to moderate-energy waves. Simulations indicated that inner-bar rip channel development, which was observed prior to the submerged reef implementation, was inhibited in the lee of the structure as rip-cell circulation across the inner bar disappeared owing to persistently low-energy breaking waves. The cross-shore sandbar dynamics in the lee of the structure were also impacted due to the drastic decrease of the offshore-directed flow over the inner-bar during energetic events. This paper highlights that implementation of a submerged breakwater results in larges changes in nearshore hydrodynamics that, in turn, can affect overall surf zone sandbar behavior.

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36

McKiver, W. J., G. Sannino, F. Braga, and D. Bellafiore. "Investigation of model capability in capturing vertical hydrodynamic coastal processes: a case study in the North Adriatic Sea." Ocean Science Discussions 12, no. 4 (August 3, 2015): 1625–68. http://dx.doi.org/10.5194/osd-12-1625-2015.

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Abstract. In this work we consider a numerical study of hydrodynamics in the coastal zone using two different models, SHYFEM and MITgcm, to assess their capability to capture the main processes. We focus on the North Adriatic Sea during a strong dense water event that occurred at the beginning of 2012. This serves as an interesting test case to examine both the models strengths and weaknesses, while giving an opportunity to understand how these events affect coastal processes, like upwelling and downwelling, and how they interact with estuarine dynamics. Using the models we examine the impact of setup, surface and lateral boundary treatment, resolution and mixing schemes, as well as assessing the importance of nonhydrostatic dynamics in coastal processes. Both models are able to capture the dense water event, though each displays biases in different regions. The models show large differences in the reproduction of surface patterns, identifying the choice of suitable bulk formulas as a central point for the correct simulation of the thermohaline structure of the coastal zone. Moreover, the different approaches in treating lateral freshwater sources affect the vertical coastal stratification. The results indicate the importance of having high horizontal resolution in the coastal zone, specifically in close proximity to river inputs, in order to reproduce the effect of the complex coastal morphology on the hydrodynamics. A lower resolution offshore is acceptable for the reproduction of the dense water event, even if specific vortical structures are missed. Finally, it is found that nonhydrostatic processes are of little importance for the reproduction of dense water formation in the shelf of the North Adriatic Sea.

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37

Franz, Guilherme, Matthias T. Delpey, David Brito, Lígia Pinto, Paulo Leitão, and Ramiro Neves. "Modelling of sediment transport and morphological evolution under the combined action of waves and currents." Ocean Science 13, no. 5 (September 7, 2017): 673–90. http://dx.doi.org/10.5194/os-13-673-2017.

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Abstract. Coastal defence structures are often constructed to prevent beach erosion. However, poorly designed structures may cause serious erosion problems in the downdrift direction. Morphological models are useful tools to predict such impacts and assess the efficiency of defence structures for different scenarios. Nevertheless, morphological modelling is still a topic under intense research effort. The processes simulated by a morphological model depend on model complexity. For instance, undertow currents are neglected in coastal area models (2DH), which is a limitation for simulating the evolution of beach profiles for long periods. Model limitations are generally overcome by predefining invariant equilibrium profiles that are allowed to shift offshore or onshore. A more flexible approach is described in this paper, which can be generalised to 3-D models. The present work is based on the coupling of the MOHID modelling system and the SWAN wave model. The impacts of different designs of detached breakwaters and groynes were simulated in a schematic beach configuration following a 2DH approach. The results of bathymetry evolution are in agreement with the patterns found in the literature for several existing structures. The model was also tested in a 3-D test case to simulate the formation of sandbars by undertow currents. The findings of this work confirmed the applicability of the MOHID modelling system to study sediment transport and morphological changes in coastal zones under the combined action of waves and currents. The same modelling methodology was applied to a coastal zone (Costa da Caparica) located at the mouth of a mesotidal estuary (Tagus Estuary, Portugal) to evaluate the hydrodynamics and sediment transport both in calm water conditions and during events of highly energetic waves. The MOHID code is available in the GitHub repository.

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38

Sokolov, Andrei, and Boris Chubarenko. "Case-Study Modelling Analysis of Hydrodynamics in the Nearshore of the Baltic Sea Forced by Extreme Along-shore Wind in the Case of a Cross-shore Obstacle." Archives of Hydro-Engineering and Environmental Mechanics 65, no. 3 (December 1, 2018): 163–76. http://dx.doi.org/10.1515/heem-2018-0011.

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AbstractIn the current study we use a three-dimensional model with hydrodynamic and spectral wave modules operating in a coupled mode to simulate the response of currents and wind wave fields to winds of 20–25 m/sec offshore of the protective structure of the Saint Petersburg Flood Prevention Facility Complex. The model was calibrated against field data, which allowed us to obtain a tool describing storm situations in the eastern part of the Gulf of Finland with a satisfactory accuracy. The numerical modeling showed that the protective dam did not have a noticeable effect on the levels of stormsurge, significantwave height, or current speed in areas seaward of the dam. The increase in erosion processes on the southern shore of the easternmost part of the Gulf of Finland in recent past has most probably been related to other factors. We found that if a west or south-west wind of at least 25 m/s blows over the Baltic Sea for at least 16 hours, the level of storm surges seaward of the dam may reach 3 or more meters. An artificial strengthening of the coastline and the creation of shore protection structures are recommended.

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39

Yeh, Harry, and Nobuo Shuto. "Tsunami Forces and Effects on Structures." Journal of Disaster Research 4, no. 6 (December 1, 2009): 375–76. http://dx.doi.org/10.20965/jdr.2009.p0375.

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The 2004 Indian Ocean Tsunami claimed more than 220,000 lives. It was a low-probability high-consequence event. A similar disaster could strike elsewhere, particularly in the Pacific but also in Caribbean, Atlantic, and Mediterranean regions. Unlike in seismic ground shaking, there is usually a short lead-time precedes tsunami attack: from a few minutes for a local source to several hours for a distant source. Because mega-tsunamis are rare and because forewarning of these events is possible, the primary mitigation tactic to date has been evacuation. Hence, most efforts have focused on the development of effective warning systems, inundation maps, and tsunami awareness. This strategy makes sense from the standpoint of saving human lives. However, it does not address the devastating damage to buildings and critical coastal infrastructure, such as major coastal bridges, oil and LNG storage facilities, power plants, and ports and harbors. Failure in critical infrastructure creates enormous economic setbacks and collateral damage. The accelerating construction of critical infrastructure in the coastal zone demands a better understanding of design methodology in building tsunamiresistant structures. In some coastal areas such as low-elevation coastal spits or plains, evacuating people to higher ground may be impractical because they have no time to reach safety. In these situations, the only feasible way to minimize human casualties is to evacuate people to the upper floors of tsunami-resistant buildings. Such buildings must be designed and constructed to survive strong seismic ground shaking and subsequent tsunami impacts. The primary causes of structural failure subject to tsunami attack can be categorized into three groups: 1) hydrodynamic force, 2) impact force by water-born objects, and 3) scour and foundation failure. Tsunami behaviors are quite distinct, however, from other coastal hazards such as storm waves; hence the effects cannot be inferred from common knowledge or intuition. Recent research has addressed tsunami forces acting on coastal structures to develop appropriate design guidelines, and mechanisms leading to tsunamigenerated scour and foundation failures. This special issue is a compilation of 14 papers addressing tsunami effects on buildings and infrastructure. The four main groupings begin with two papers on tsunami force acting on vertical walls. Arikawa experimentally investigates the structural performance of wooden and concrete walls using a large-scale laboratory tank in Japan. Also using a similar large-scale tsunami flume but in the US, Oshnack et al. study force reduction by small onshore seawalls in front of a vertical wall. The second grouping focuses on tsunami force on 3-D structures. Arnason et al. present a basic laboratory study on the hydrodynamics of bore impingement on a vertical column. Fujima et al. examine the two types of formulae for tsunami force evaluation: the one calculated from flow depth alone and the other based on the Euler number. Lukkunaprasit et al. demonstrate the validity of force computation recommended in a recently published design guideline (FEMA P646) by the US Federal Emergency Management Agency. The other two papers look into the specific types of structures: one is for light-frame wood buildings by van de Lindt et al, and the other is for oil storage tanks by Sakakiyama et al. The topic of debris impact force is the focus of the third grouping. Matsutomi summarizes his previous research on impact force by driftwoods, followed by the collision force of shipping containers by Yeom et al. Yim and Zhang numerically simulate tsunami impact on a vertical cylinder; this paper is included in this grouping because their numerical approach is similar to that of Yeom et al. As for the fourth grouping, Shuto presents field observations on foundation failures and scours, and Fujii et al. discuss the erosion processes of soil embankments. There are two more papers: those are the application of fragility analysis to tsunami damage assessment by Koshimura et al. and evaluation of an offshore cabled observatory by Matsumoto and Kaneda. The topics presented here are undoubtedly in progress, and many revisions and improvements are still needed in order to achieve better predictability for tsunami effects on buildings and infrastructure. We hope you find the papers in this issue intriguing and the information useful, and become further interested in this important natural hazard. Lastly, we wish to express our appreciation to the authors for their timely contributions, and to the reviewers for their diligent and time-consuming efforts.

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40

Orszaghova, J., H. Wolgamot, S. Draper, R. Eatock Taylor, P. H. Taylor, and and A. Rafiee. "Transverse motion instability of a submerged moored buoy." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 475, no. 2221 (January 2019): 20180459. http://dx.doi.org/10.1098/rspa.2018.0459.

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Wave energy converters and other offshore structures may exhibit instability, in which one mode of motion is excited parametrically by motion in another. Here, theoretical results for the transverse motion instability (large sway oscillations perpendicular to the incident wave direction) of a submerged wave energy converter buoy are compared to an extensive experimental dataset. The device is axi-symmetric (resembling a truncated vertical cylinder) and is taut-moored via a single tether. The system is approximately a damped elastic pendulum. Assuming linear hydrodynamics, but retaining nonlinear tether geometry, governing equations are derived in six degrees of freedom. The natural frequencies in surge/sway (the pendulum frequency), heave (the springing motion frequency) and pitch/roll are derived from the linearized equations. When terms of second order in the buoy motions are retained, the sway equation can be written as a Mathieu equation. Careful analysis of 80 regular wave tests reveals a good agreement with the predictions of sub-harmonic (period-doubling) sway instability using the Mathieu equation stability diagram. As wave energy converters operate in real seas, a large number of irregular wave runs is also analysed. The measurements broadly agree with a criterion (derived elsewhere) for determining the presence of the instability in irregular waves, which depends on the level of damping and the amount of parametric excitation at twice the natural frequency.

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41

Jin, Weixia, and Michael McCarthy. "BOLSA CHICA WETLANDS RESTORATION INLET DESIGN." Coastal Engineering Proceedings 1, no. 32 (February 2, 2011): 46. http://dx.doi.org/10.9753/icce.v32.management.46.

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Bolsa Chica Wetlands is one of a few recently restored large wetlands in Southern California of the United States. The project required restoration of tidal flooding of some isolated wetlands while minimizing impacts to the shoreline adjacent to the new inlet and maintenance costs, preserving endangered species on site, and maintaining oil field operations along the periphery of the project. The project created a direct connection to the ocean through wetland basins that included a full tidal basin, muted tidal basins and seasonal ponds linked by a series of ocean jetties, levees, water control structures, culverts, and channels. The inlet is a key project feature and has been the focus of numerous technical studies and numerical modeling tasks. As part of theses analyses, a pre-filled ebb bar was designed and about 1 million cubic yards of clean sand from the lowlands dredging was placed offshore to minimize the anticipated impacts of the inlet opening to the shoreline. This paper presents the inlet location selection, inlet and wetland hydrodynamics, inlet dimension optimization, inlet stability analyses, and jettied inlet entrance design. It also discusses findings of comparison between model predictions and field measurements of tidal elevations and sediment accumulations in the wetland basin since the completion of the project in August 2006. This project received the first Project Excellence Award from COPRI (Coasts, Oceans, Ports and Rivers Institute) of the American Society of Civil Engineers in 2008.

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42

Fujino, Masataka, Hiroshim Kagemoto, Takashi Nakatubo, and Shinobu Nakatuka. "Hydrodynamic Characteristics of Permeable Offshore Structures." Journal of the Society of Naval Architects of Japan 1992, no. 172 (1992): 93–103. http://dx.doi.org/10.2534/jjasnaoe1968.1992.172_93.

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43

Rahman, M. "Nonlinear Hydrodynamic Loading on Offshore Structures." Theoretical and Computational Fluid Dynamics 10, no. 1-4 (January 1, 1998): 323–47. http://dx.doi.org/10.1007/s001620050067.

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44

Clauss, G. F., and L. Birk. "Hydrodynamic shape optimization of large offshore structures." Applied Ocean Research 18, no. 4 (August 1996): 157–71. http://dx.doi.org/10.1016/s0141-1187(96)00028-4.

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45

Chen, Xiaobo. "Offshore hydrodynamics and applications." IES Journal Part A: Civil & Structural Engineering 4, no. 3 (August 2011): 124–42. http://dx.doi.org/10.1080/19373260.2011.595903.

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46

Kim, Mun Sung, Kwang Hyo Jung, and Sung Boo Park. "WAVE INDUCED COUPLED MOTIONS AND STRUCTURAL LOADS BETWEEN TWO OFFSHORE FLOATING STRUCTURES IN WAVES." Brodogradnja 69, no. 3 (July 1, 2018): 149–73. http://dx.doi.org/10.21278/brod69309.

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As oil or gas field moves deeper offshore area, offshore offloading operations such as Tandem or Side-by-Side arrangement between two floating structures take place in many locations throughout the world and also have many hydrodynamic problems. Therefore, the researches on the motion response and hydrodynamic force including first and second order between two floating structures are needed to have the more safe offloading operability in waves. In this paper, prediction of wave induced motion responses and structural loads at mid-ship section with hydrodynamic interaction effect between two offshore floating structures in various heading waves are studied by using a linearized three-dimensional potential theory. Numerical calculations using three-dimensional pulsating source distribution techniques have been carried out for hydrodynamic pressure distribution, wave exciting force, twelve coupled linear motion responses, relative motions and wave loads of the barge and the ship in oblique waves. The computational results give a good correlation with the experimental results and also with other numerical results. As a result, the present computational tool can be used effectively to predict the wave induced motions and structural loads of multiple offshore floating structures in waves.

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47

Gudmestad, Ove T., and Geir Moe. "Hydrodynamic coefficients for calculation of hydrodynamic loads on offshore truss structures." Marine Structures 9, no. 8 (September 1996): 745–58. http://dx.doi.org/10.1016/0951-8339(95)00023-2.

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48

Sun, Keming, and Toyoaki Nogami. "Earthquake induced hydrodynamic pressure on axisymmetric offshore structures." Earthquake Engineering & Structural Dynamics 20, no. 5 (1991): 429–40. http://dx.doi.org/10.1002/eqe.4290200504.

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49

Zhou, Jifu, Ling Chen, and Xu Wang. "Hydrodynamic scaling and wave force estimation of offshore structures." Acta Mechanica Sinica 36, no. 6 (October 28, 2020): 1228–37. http://dx.doi.org/10.1007/s10409-020-01007-5.

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50

Avilés, Javier, and Xiangyue Li. "Hydrodynamic pressures on axisymmetric offshore structures considering seabed flexibility." Computers & Structures 79, no. 29-30 (November 2001): 2595–606. http://dx.doi.org/10.1016/s0045-7949(01)00125-0.

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