Assessment of the Power Output of a Two-Array Clustered WEC Farm Using a BEM Solver Coupling and a Wave-Propagation Model
Abstract
:1. Introduction
2. Theoretical Background
2.1. Linear Potential Flow
- the fluid is inviscid;
- the fluid is incompressible; and
- the flow is irrotational.
2.2. Boundary Element Method Solver
2.3. Mild-Slope Wave Propagation Model
3. Coupling Methodology
3.1. Modeled WECs
3.2. WEC Array and WEC Farm Layout
3.3. Coupling of NEMOH to MILDwave
3.4. Calculating the Total Wave Field of the Perturbed Sea State—Demonstration for a Regular Wave
3.5. Coupling Irregular Waves
4. Determining the Power Output of a Nine-WEC Array
5. Regular Wave Results
5.1. Wave Field around two WEC Arrays within a WEC Farm in Regular Waves
5.2. Power Output of a WEC Farm Composed of Two WEC Arrays in Regular Waves
5.2.1. Wave Incidence at = 0
5.2.2. Wave Incidence at = 22.5 and 45
5.3. Quantifying Percent Difference between Pfarm and Pisolated
6. Irregular Wave Results
6.1. Wave Field around Two WEC Arrays within a WEC Farm in Irregular Waves
6.2. Power Output of a WEC Farm Composed of Two WEC Arrays in Irregular Waves
7. Defining ’Hydrodynamic Independence’ in a WEC Farm Composed of Two WEC Arrays
8. Discussion
9. Conclusions
Author Contributions
Funding
Conflicts of Interest
Abbreviations
DoF | Degree of Freedom |
PTO | Power Take-Off |
RAO | Response Amplitude Operator |
WEC | Wave Energy Converter |
angle of incidence of the incoming wave to the x-axis () | |
, | intra-array WEC separation distances in the x and y direction (m) |
linear power-take-off damping coefficient (kg/s) | |
interarray centre-to-centre separation distance (m) | |
M | number of bodies in the WEC array |
N | number of frequencies in irregular sea state discretization |
free-surface elevation (m) | |
absolute value of the wave amplitude (m) | |
perturbed wave of order j for array i (-) | |
mechanical power produced by the WEC for a given frequency and wave direction (kW) | |
coupling radius (m) | |
P | 2 × total power output of an isolated WEC array (kW) |
P | total power output of a WEC farm (kW) |
resonance or natural period of an oscillating body (s) | |
complex amplitude of heave velocity of body j (m/s) | |
complex wave amplitude i (m) | |
array effects = hydrodynamic effects of WECs in an array that produce a perturbation in the incident wave field | |
perturbed wave = radiated + diffracted wave |
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Balitsky, P.; Verao Fernandez, G.; Stratigaki, V.; Troch, P. Assessment of the Power Output of a Two-Array Clustered WEC Farm Using a BEM Solver Coupling and a Wave-Propagation Model. Energies 2018, 11, 2907. https://doi.org/10.3390/en11112907
Balitsky P, Verao Fernandez G, Stratigaki V, Troch P. Assessment of the Power Output of a Two-Array Clustered WEC Farm Using a BEM Solver Coupling and a Wave-Propagation Model. Energies. 2018; 11(11):2907. https://doi.org/10.3390/en11112907
Chicago/Turabian StyleBalitsky, Philip, Gael Verao Fernandez, Vasiliki Stratigaki, and Peter Troch. 2018. "Assessment of the Power Output of a Two-Array Clustered WEC Farm Using a BEM Solver Coupling and a Wave-Propagation Model" Energies 11, no. 11: 2907. https://doi.org/10.3390/en11112907