1. Introduction 2. Mathematical description of oscillations 3. Interaction between oscillations and waves 4. Gravity waves on water 5. Wave-body interactions 6. Wave-energy absorption by oscillating bodies 7. Wave interactions with oscillating water columns Bibliography Index.

https://assets.cambridge.org/97805217/82111/copyright/9780521782111_copyright.pdf

Ocean waves and oscillating systems : linear interactions including wave-energy extraction

This paper deals with three-dimensional water-wave diffraction and radiation by a structure consisting of a number of separate (vertically) non-overlapping members in the context of linearised potential flow. An interaction theory is developed which solves the complete problem, predicting wave exciting forces, hydrodynamic coefficients and second-order drift forces, but is based algebraically on the diffraction characteristics of single members only. This method, which includes also the diffraction interaction of evanescent waves, is in principle exact (within the context of linearised theory) for otherwise arbitrary configurations and spacings. This is confirmed by a number of numerical examples and comparisons involving two or four axisymmetric legs, where full three-dimensional diffraction calculations for the entire structures are also performed using a hybrid element method. To demonstrate the efficacy of the interaction theory, it is applied to an array of 33 (3 by 11) composite cylindrical legs, where experimental data are available. The comparison with measurements shows reasonable agreement. The present method is valid for a large class of arrays of arbitrary individual geometries, number and configuration of bodies with non-intersecting vertical projections. Its application should make it unnecessary to perform full diffraction computations for many multiple-member structures and arrays.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022112086000101

Interactions among multiple three-dimensional bodies in water waves: an exact algebraic method

During the past few decades, wave energy has received significant attention for harnessing ocean energy. Industry has proposed many technologies and, based on their working principle, these technologies generally can be categorized into oscillating water columns, point absorbers, overtopping systems, and bottom-hinged systems. In particular, many researchers have focused on modeling the point absorber, which is thought to be the most cost-efficient technology to extract wave energy. To model such devices, several modeling methods have been used such as analytical methods, boundary integral equation methods and Navier–Stokes equation methods. The first two are generally combined with the use of empirical solution to represent the viscous damping effect, while the last one is directly included in the solution. To assist the development of wave energy conversion (WEC) technologies, this paper extensively reviews the methods for modeling point absorbers.

/pdf/a-synthesis-of-numerical-methods-for-modeling-wave-energy-2fstcj9wlt.pdf

A synthesis of numerical methods for modeling wave energy converter-point absorbers

State-space modelling of a vertical cylinder in heave

Optimal configurations of wave energy device arrays

The phenomenon of negative added mass is studied by considering the heave oscillations of a submerged vertical cylinder. Free-surface effects are shown to be important for the occurrence of negative added mass. Rapid changes in the added mass and damping, as functions of frequency of oscillation, often associated with this phenomenon are explained in terms of near-resonant standing waves above the body.

The occurrence of negative added mass in free-surface problems involving submerged oscillating bodies

Previous work on the scattering of an incident wave field by an array of fixed vertical cylinders is extended to calculate the added-mass and damping coefficients for an array of floating axisymmetric bodies. The method is based upon a large spacing approximation where diverging waves are replaced by plane waves. It is shown that, given the scattering and radiation properties of a single body, the interaction effects within an array can be calculated both simply and accurately.

P. Mciver

Papers

The occurrence of negative added mass in free-surface problems involving submerged oscillating bodies

Wave forces on arrays of floating bodies