On the radiation and diffraction of linear water waves by a rectangular structure over a sill. Part I. Infinite domain of finite water depth

Shen, Y.M.; Zheng, Yh H.; You, Yan

doi:10.1016/j.oceaneng.2004.07.011

Cited by 36 publications

(16 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…He presented added mass and damping coefficient and free surface elevation in the moon pool for a range of wave numbers, with singular results in the resonant regime. Shen et al [14] analyzed the effect of a bottom sill on the hydrodynamic coefficients, wave force, and reflection and transmission coefficients of a rectangular structure floating on the free surface. Zhou et al [15] derived the radiation and diffraction of water waves by a rectangular body with an opening in its bottom in water of finite depth.…”

Section: Introductionmentioning

confidence: 99%

Hydrodynamic coefficients in surge for a radiating hollow cylinder placed above a coaxial cylinder at finite ocean depth

Hassan

Bora

2014

J Mar Sci Technol

View full text Add to dashboard Cite

Hydrodynamic coefficients due to horizontal oscillation in surge motion for a floating, hollow cylinder placed above a fixed, coaxial, bottom-mounted cylinder are investigated within the framework of linear, water wave theory. This problem of radiation by this specific pair of two cylinders can be considered as a wave energy device consisting of two coaxial cylinders: the upper one hollow and the lower one solid. The energy that is created and transferred by this device finds use in a number of practical applications. We use the method of separation of variables to obtain the analytical expressions for the corresponding radiated potentials in clearly identified regions. By using the matching conditions which ensure the continuity of velocity and pressure along the virtual vertical boundaries of the regions, a system of linear equations for the unknown coefficients is derived and solved. The analytical expressions of the radiated potentials allow us to obtain the hydrodynamic coefficients, namely, the added mass and damping coefficients, which play a vital role for a structure in motion, however small. A set of values of added mass and damping coefficients is obtained for different radii of the fixed cylinder and for different gaps between the cylinders (i.e., also for different drafts of the floating cylinder) for the same fixed radii of the cylinders. It is observed that changes in values in radius and the gap have significant effect on the hydrodynamic coefficients. We also compute the coefficients due to different gaps between the cylinders with the radii of both taken to be different. The behaviour of both the added mass and damping coefficients is observed to be steady in the lower frequency range.However, fluctuations are observed for both coefficients due to resonance in the neighbourhood of a specific frequency. These results are depicted graphically and compared with available results. Comparison is carried out with numerical data presented by other investigators by considering the case of a hollow cylinder floating over an even sea bottom, i.e., without the coaxial cylindrical caisson underneath. Good agreement is observed from this comparison. A numerical verification is also carried out for the body boundary condition satisfied at the boundary of both the cylinders.

show abstract

Section: Introductionmentioning

confidence: 99%

Hydrodynamic coefficients in surge for a radiating hollow cylinder placed above a coaxial cylinder at finite ocean depth

Hassan

Bora

2014

J Mar Sci Technol

View full text Add to dashboard Cite

show abstract

“…From the above discussions, we have seen that to get hydrodynamic forces, we have to determine the associated} unknown coefficients appearing in the above expressions of radiated potentials given by the equations (15-19) with the help of matching conditions (10)(11)(12)(13)(14). As every expression of potential is found to be a series with infinite terms, therefore to calculate the corresponding values, we must be truncated appropriately after some terms.…”

Section: Resultsmentioning

confidence: 99%

“…Let us consider the total radiated potential due to surge motion be r  . Therefore the radiated potential r  is given by ( [10]…”

Section: B Governing Equation and Boundary Conditionsmentioning

confidence: 99%

Radiated Force due to Surge Motion by a Pair of Submerged Cylinder in Water

Borah¹,

Konch²

2019

IJITEE

View full text Add to dashboard Cite

Evaluation of hydrodynamic coefficients due to surge of submerged structure is great significant to designing a device which can be consider as a device of wave energy. In the present work, a theoretical approach is developed to describe radiation of water wave by fully submerged cylinder placed above a submerged circular plate in water of finite depth which is based on linear water wave theory The radiation problem due to surge motion by this pair of cylinders have investigated with the suspicion of linear water wave theory. To determine the radiated potentials in every area, we utilize the eigenfunction expansion method and variables separation method. Finally, we derived the analytical expressions of Hydrodynamic coefficients i. e. added mass and damping coefficient due to surge and associated unknown coefficients are calculated by utilizing the matching conditions between the physical and virtual boundaries. A set of added mass and damping coefficient have presented graphically for various radius of the submerge cylinder.

show abstract

“…Zheng et al [15,16] studied the diffraction and radiation of a square floating structure under the condition of three-dimensional wave incidence, and analyzed the influence of different incident wave directions on the force and hydrodynamic performance of the WEC by using the eigenfunction expansion matching method. Shen et al [17] used a semi-analytical method to solve the parameters of the wave excitation force and additional mass of the cylindrical WEC. Vantorre et al [18] employed a software named AQUA+ to study floating structures with cylindrical, conical and hemispherical shapes at the bottom.…”

Section: Introductionmentioning

confidence: 99%

Study on the Optimal Wave Energy Absorption Power of a Float in Waves

Luan

Zhang

et al. 2019

JMSE

View full text Add to dashboard Cite

The utilization of ocean renewable energy, especially wave energy, is of great significance in ocean engineering. In this study, a three-dimensional numerical wave tank was established to simulate the wave-float interaction based on the Reynolds-averaged Navier–Stokes equations and the Realizable K-Epsilon Two-Layer turbulence model was applied. Firstly, convergence studies with respect to the mesh and time step were carried out and confirmed by the published analytical and numerical data. Then, the resonance condition of a particular float was solved by both numerical and analytical methods. The numerical and the analytical results are mutually verified in good agreements, which verify the reliability of the analytical process. Furthermore, a wave energy converter (WEC) consisting of a single float without damping constant was adopted, and its hydrodynamic performance in different wave conditions was investigated. It was found that the damping factor can affect the motion response of the float and the wave force it receives. Under a certain wavelength condition, the WEC resonates with the wave, at which the wave force on the float, displacement of the float and other parameters reach a maximum value. Finally, the influence of linear damping constant on the power take-off (PTO) was studied. The results show that the damping factor does not affect the wave number turning point of the optimal damping constant.

show abstract

On the radiation and diffraction of linear water waves by a rectangular structure over a sill. Part I. Infinite domain of finite water depth

Cited by 36 publications

References 16 publications

Hydrodynamic coefficients in surge for a radiating hollow cylinder placed above a coaxial cylinder at finite ocean depth

Hydrodynamic coefficients in surge for a radiating hollow cylinder placed above a coaxial cylinder at finite ocean depth

Radiated Force due to Surge Motion by a Pair of Submerged Cylinder in Water

Study on the Optimal Wave Energy Absorption Power of a Float in Waves

Contact Info

Product

Resources

About