# Optimization on Hydrodynamic Performance for First Level Energy-Capturing Enhancement of a Floating Wave Energy Converter System with Flapping-Panel-Slope

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## Abstract

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## 1. Introduction

## 2. A Floating Flapping-Panel WEC

## 3. Model Test

## 4. Results & Discussion

#### 4.1. Relationship between Slope Angle and Power

#### 4.2. Relationship between PTO Damping Coefficients and Power

_{P}= 10 m and T = 5 s, which was not conducive to structural stability. The floating flapping-panel worked well when ${L}_{P}=10$ m and $T=6\mathrm{s}$. When ${L}_{P}=10\mathrm{m}$ and $T=7\mathrm{s}$, the floating flapping-panel returned to the origin and continued to move downward, which would result in a waste of wave energy. In summary, long flapping-panel caused a long time of wave action. However, since the floating flapping-panel contacted wave surface earlier when moving downward, it cannot return to the initial position. In the case of short flapping-panel length, the floating flapping-panel would return to the initial position as expected to achieve resonance.

#### 4.3. Physical Model Preliminary Test

## 5. Conclusions & Future work

- The simulation test study showed that the angle between the slope and the horizontal plane significantly influenced the efficiency of the wave energy converter. The optimal slope angle is 35 degrees, and the wave energy captured in the experimental sea conditions is the largest.
- Meanwhile, from the output characteristics under different PTO damping coefficients for the linear damping, an optimal coefficient was obtained to give maximum captured energy. The wave energy converter became more efficient as PTO damping coefficients fell.
- The length of the flapping-panel will affect the efficiency and resonance of the wave energy converter. With the increase of incident wave height, the wave energy converter can capture more energy.
- In the follow-up work, we will continue to carry out in-depth research around it, optimize the design and achieve high-efficiency capture of wave energy.

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## References

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$\mathit{T}/\mathbf{s}$ | ${\mathit{E}}_{\mathit{m}}/\mathbf{k}\mathbf{J}$ | ${\mathit{W}}_{\mathit{P}\mathit{T}\mathit{O}}/\mathbf{k}\mathbf{J}$ | ${\mathit{P}}_{\mathit{P}\mathit{T}\mathit{O}}/\mathbf{K}\mathbf{W}$ | ${\mathit{c}}_{\mathit{f}}/\mathbf{\%}$ |
---|---|---|---|---|

5 | 100 | 66.2 | 47.6 | 66.2 |

6 | 144 | 86.1 | 64.3 | 59.8 |

7 | 196 | 83.6 | 62.6 | 42.7 |

$\mathit{T}/\mathbf{s}$ | ${\mathit{L}}_{\mathit{P}}/\mathbf{m}$ | ${\mathit{P}}_{\mathit{P}\mathit{T}\mathit{O}}/\mathbf{K}\mathbf{W}$ | ${\mathit{W}}_{\mathit{P}\mathit{T}\mathit{O}}/\mathbf{k}\mathbf{J}$ | ${\mathit{c}}_{\mathit{f}}/\mathbf{\%}$ |
---|---|---|---|---|

5 | 8 | 47.3 | 65.8 | 65.8 |

10 | 48.6 | 75.4 | 75.4 | |

6 | 8 | 64 | 85.8 | 60 |

10 | 63.7 | 94.9 | 66 | |

7 | 8 | 62.3 | 83 | 42.3 |

10 | 61.3 | 93 | 47.4 |

Wave tank width/m | 0.5 |

Water depth/m | 0.6 |

Water density/${10}^{3}\mathrm{kg}\xb7{\mathrm{m}}^{-3}$ | 1.025 |

Gravity acceleration/$\mathrm{m}\xb7{\mathrm{s}}^{-2}$ | 9.81 |

Flapping-panel width/m | 0.4 |

Slope angle/° | 30 |

Bracket quality/kg | 0.81 |

Single weight quality/kg | 1 |

Water period/s | 1.2, 1.4, 1.6, 1.9,2.5, |

Wave height/m | 0.06 |

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## Share and Cite

**MDPI and ACS Style**

Song, T.; Li, Z.; Zheng, H.; Liang, C.; Wan, Z.
Optimization on Hydrodynamic Performance for First Level Energy-Capturing Enhancement of a Floating Wave Energy Converter System with Flapping-Panel-Slope. *J. Mar. Sci. Eng.* **2023**, *11*, 345.
https://doi.org/10.3390/jmse11020345

**AMA Style**

Song T, Li Z, Zheng H, Liang C, Wan Z.
Optimization on Hydrodynamic Performance for First Level Energy-Capturing Enhancement of a Floating Wave Energy Converter System with Flapping-Panel-Slope. *Journal of Marine Science and Engineering*. 2023; 11(2):345.
https://doi.org/10.3390/jmse11020345

**Chicago/Turabian Style**

Song, Tianyu, Ze Li, Honghao Zheng, Chujin Liang, and Zhanhong Wan.
2023. "Optimization on Hydrodynamic Performance for First Level Energy-Capturing Enhancement of a Floating Wave Energy Converter System with Flapping-Panel-Slope" *Journal of Marine Science and Engineering* 11, no. 2: 345.
https://doi.org/10.3390/jmse11020345