# The Influence of Ramp Shape Parameters on Performance of Overtopping Breakwater for Energy Conversion

^{1}

^{2}

^{3}

^{4}

^{*}

## Abstract

**:**

## 1. Introduction

## 2. Materials and Methods

#### 2.1. Experimental Setup

#### 2.2. Simulation Setup

## 3. Results and Discussion

_{reservoir}) by dividing to the time domain as shown in Equation (4);

_{reservoir}is taken from the results between the 30th and 50th s, which is considered stable for analysis as shown in Figure 11.

^{3}for 60 s running time. This discovery is believed to be due to the accumulation of wave run-up energy, which provided a large platform for gathering the volume of water and, therefore, indirectly increasing the mass momentum of the run-up wave above the ramp shape as expected by European group manual assessment [18], who gave the same reason for the effect of curved dike ramp on wave overtopping.

^{*}is a non-dimensional average overtopping discharge in the reservoir, g is gravity, H

_{s}is significant wave height in (m), R

^{*}is relative crest freeboard and Rr is crest freeboard of front reservoir (m).

^{2}of both shapes shows slightly lower with 52% variation with the trend line. It indicates that more experimental data are required to fit the regression lines of the exponential equation as presented by most of the previous overtopping prediction formulas [18].

## 4. Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 17.**Image showing that ramp shapes (concave, convex, cubic (-)) and angle at the crest will influence the overtopping discharge on OBREC devices.

**Figure 19.**Comparison of non-dimensional overtopping discharge between cubic and linear shape to the previous studies.

Illustration | References | Name | Ramp Shapes |
---|---|---|---|

[1,19] | Tapered Channel (TAPCHAN) | Linear | |

BLOW JET | |||

[6] | Wave Plane (WP) | Prismatic | |

(V shape) | |||

Linear | |||

[4,20] | Wave Dragon (WD) | Linear | |

Concave | |||

Concave | |||

Ellipse | |||

[3,21] | Sea Slot Cone Generator (SSG) | Linear | |

Concave | |||

Convex | |||

[7] | Wave Catamaran (WAVECAT) | Hull | |

[5,22,23] | Spiral Reef Overtopping Wave Energy Converter (OWEC) | Parabolic | |

[2] | Composite Sea Wall for Energy Conversion (CSWEC) | Linear | |

Wall/Vertical | |||

[13] | Overtopping Breakwater for Energy Conversion (OBREC) | Linear | |

Curve |

Ramp Shape Name | Polynomial Equation | 2D Illustrate | 3D Illustration |
---|---|---|---|

Linear | $\mathrm{f}\left(\mathrm{x}\right)=-0.34\mathrm{x}+3$ | ||

Convex | $\mathrm{f}\left(\mathrm{x}\right)=-0.037{\mathrm{x}}^{2}-0.009\mathrm{x}+3$ | ||

Concave | $\mathrm{f}\left(\mathrm{x}\right)=0.037{\mathrm{x}}^{2}-0.66\mathrm{x}+3$ | ||

Cubic | $\mathrm{f}\left(\mathrm{x}\right)=-0.015{\mathrm{x}}^{3}+0.191{\mathrm{x}}^{2}-0.924\mathrm{x}+3$ | ||

Cubic (-ve) | $\mathrm{f}\left(\mathrm{x}\right)=0.015{\mathrm{x}}^{3}-0.191{\mathrm{x}}^{2}+0.27\mathrm{x}+3$ | ||

Quantic | $\mathrm{f}\left(\mathrm{x}\right)=-0.0025{\mathrm{x}}^{5}+0.0543{\mathrm{x}}^{4}-0.415{\mathrm{x}}^{3}+1.29{\mathrm{x}}^{2}-1.729\mathrm{x}+3$ | ||

Quantic(-ve) | $\mathrm{f}\left(\mathrm{x}\right)=0.0025{\mathrm{x}}^{5}-0.0543{\mathrm{x}}^{4}+0.415{\mathrm{x}}^{3}-1.29{\mathrm{x}}^{2}+1.05\mathrm{x}+3$ |

Data Period | Period T_{p} (s) | Significant Wave Height H_{s} (m) |
---|---|---|

Average wave per year (R2) | 6.67 | 1.245 |

Average Northeast monsoon (R4) | 7.74 | 1.76 |

Average Southeast monsoon (R1) | 4.99 | 0.79 |

Average max wave per year (R3) | 7.13 | 1.53 (H_{max}) |

Shape Type | Simulation | Experiment | Descriptions |
---|---|---|---|

Linear | Medium overtopping | ||

Concave | Medium overtopping | ||

Convex | Medium overtopping | ||

Cubic(-ve) | Higher overtopping | ||

Cubic | Low overtopping | ||

Quantic(-ve) | Low overtopping | ||

Quantic | Low overtopping |

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**MDPI and ACS Style**

Musa, M.A.; Roslan, M.F.; Ahmad, M.F.; Muzathik, A.M.; Mustapa, M.A.; Fitriadhy, A.; Mohd, M.H.; Rahman, M.A.A.
The Influence of Ramp Shape Parameters on Performance of Overtopping Breakwater for Energy Conversion. *J. Mar. Sci. Eng.* **2020**, *8*, 875.
https://doi.org/10.3390/jmse8110875

**AMA Style**

Musa MA, Roslan MF, Ahmad MF, Muzathik AM, Mustapa MA, Fitriadhy A, Mohd MH, Rahman MAA.
The Influence of Ramp Shape Parameters on Performance of Overtopping Breakwater for Energy Conversion. *Journal of Marine Science and Engineering*. 2020; 8(11):875.
https://doi.org/10.3390/jmse8110875

**Chicago/Turabian Style**

Musa, M. A., M. F. Roslan, M. F. Ahmad, A. M. Muzathik, M. A. Mustapa, A. Fitriadhy, M. H. Mohd, and M. A. A. Rahman.
2020. "The Influence of Ramp Shape Parameters on Performance of Overtopping Breakwater for Energy Conversion" *Journal of Marine Science and Engineering* 8, no. 11: 875.
https://doi.org/10.3390/jmse8110875