Impact of wave interactions effects on energy absorption in large arrays of wave energy converters

Abstract

This paper presents a parametric study on arrays of wave energy converters (WECs). Its goal is to assess the influence of interactions between bodies on the overall yearly energy production of the array. Generic WECs (heaving cylinder and surging barge) are considered. Nine to twenty-five WECs are installed along regular square and triangular grids; the influence of the separating distance between the WECs is investigated. Results show that constructive and destructive interactions compensate each other over the considered range of wave periods. The influence of the separating distance can be limited, especially if the damping of the power takeoff is tuned properly, and if the WECs have a large bandwidth. It is found that grouping the devices into arrays have generally a constructive effect. Diffracted and radiated waves in the array lead to a sufficient increase in the energy absorption which overcomes the reduction due to masking effects.

Experimental Validation of a Wave Energy Converter Array Hydrodynamics Tool

“…In the laboratory, the PTO was required to behave as a linear damper, i.e., the moment exerted by the electric motor was targeted to be directly proportional to the angular velocity (see Section 3). Even though more sophisticated control strategies may be used to improve performance of WECs, the simple implementation of linear damping control makes it suitable for full scale WECs and also applicable to most WEC designs; therefore, it has been generally used in numerical models as the control strategy for a generic WEC and for WEC arrays, such as in [8][9][10][11][12][13] and in [16]. Additionally, and unlike other types of PTO systems, such as Coulomb dampers, linear dampers allow the physical model parameters and results to be scaled, as mentioned before, through Froude's scaling law.…”

“…control strategy for a generic WEC and for WEC arrays, such as in [8][9][10][11][12][13] and in [16]. Additionally, and unlike other types of PTO systems, such as Coulomb dampers, linear dampers allow the physical model parameters and results to be scaled, as mentioned before, through Froude's scaling law.…”

“…Figure 9 shows the predicted (blue line) and measured (red line) resultant moment amplitude for the radiation test and for each WEC. The first is obtained through Equation (11) and the second through Equation (10).…”

Optimal Configurations of Wave Energy Converter Arrays with a Floating Body

“…The interaction factor is found to be equal to unity over all the incident wave directions 0~2 π. The most recent studies on the interactions correspond to researchers [5][6][7][8][9][10][11][12] Weller et al [6] examined the interaction factors of the floaters array through experiment measurement in regular and irregular waves and found that whether the interaction is positive depends on the displacements of the floaters, incident wave periods and the performance of adjacent devices. Child and Venugopal [7] optimized a generic point absorbers array by adjusting the incident wave directions and the array layouts through two different methods (parabolic intersection and genetic algorithm methods).…”

Modeling Link for Ocean Wave Energy of Point Absorbers: A Mathematical Framework

“…This way, f becomes √ 11.25r, keeping the bodies more stretched in the x-direction than in the y one. The reason for choosing latter cases relies on the results determined by [39,40], which refer to that triangular and squared/diamond array layouts as fairly suited for Ocean Wave Energy extraction [41].…”