# Performance Assessment of a Semi-Circular Breakwater through CFD Modelling

^{1}

^{2}

^{3}

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^{*}

## Abstract

**:**

## 1. Introduction

## 2. Methods

#### 2.1. Flow Model

#### 2.2. Breakwater Geometry

#### 2.3. Numerical Model

#### 2.4. Simulated Scenarios

## 3. Results

## 4. Discussion

_{i}

^{2}, where γ is the fluid specific weight), and the dimensionless incident wave parameter (H

_{i}/gT

^{2}) were inserted (red dots) in the monogram (Figure 7).

_{i}/gT

^{2}) increases, the stability parameter (W/γH

_{i}

^{2}) decreases. This behaviour can be explained by the fact that the longer period waves exert greater forces on the structure, when compared to short waves period. This was already concluded by [22].

## 5. Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**Cross-section of the semicircular breakwater model with a rubble mound foundation (data from [22]).

**Figure 4.**Results of pressure and dimensionless free surface elevation (Z*) along the dimensionless channel length (Y*) at the instant when the horizontal component of the pressure force is maximum (left) and variation of the horizontal pressure force over the simulation time (right).

**Figure 5.**Turbulent kinetic energy: perforated semicircular breakwater (left) and non-perforated semicircular breakwater (right).

**Figure 6.**Turbulent kinetic energy dissipation: perforated semicircular breakwater (left) and non-perforated semicircular breakwater (right).

**Figure 7.**Monogram of experimental results (data from [22])—gray dots) and results obtained from numerical simulations of scenarios 1 to 5 (red dots).

**Figure 8.**Water surface elevation at different probes for scenarios 2, 5, 7, 8, 9 and 11 (the elevations were dimensioned using the maximum value at probe 1 for scenario 2).

Type of Breakwater | Scenarios | d (m) | L (m) | H_{i} (m) | T (s) | Boundary Wave Type | (d/L) |
---|---|---|---|---|---|---|---|

Perforated | 1 | 1.75 | 13.5 | 0.3 | 3.58 | Stokes | Intermediate |

2 | 2.00 | 18.7 | 0.6 | 4.52 | Stokes | Intermediate | |

3 | 2.00 | 12.3 | 0.6 | 3.19 | Stokes | Intermediate | |

4 | 2.00 | 15.8 | 0.6 | 3.91 | Stokes | Intermediate | |

5 | 1.75 | 12.7 | 0.8 | 3.41 | Stokes | Intermediate | |

6 | 1.20 | 24.30 | 0.5 | 7.20 | Solitary | Shallow | |

7 | 1.00 | 24.0 | 0.3 | 7.60 | Cnoidal | Shallow | |

Non perforated | 8 | 2.00 | 18.7 | 0.6 | 4.52 | Stokes | Intermediate |

9 | 1.75 | 12.7 | 0.8 | 3.41 | Stokes | Intermediate | |

10 | 1.20 | 24.3 | 0.5 | 7.20 | Solitary | Shallow | |

11 | 1.00 | 24.0 | 0.3 | 7.60 | Cnoidal | Shallow |

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**MDPI and ACS Style**

Gomes, A.; Pinho, J.L.S.; Valente, T.; Antunes do Carmo, J.S.; V. Hegde, A. Performance Assessment of a Semi-Circular Breakwater through CFD Modelling. *J. Mar. Sci. Eng.* **2020**, *8*, 226.
https://doi.org/10.3390/jmse8030226

**AMA Style**

Gomes A, Pinho JLS, Valente T, Antunes do Carmo JS, V. Hegde A. Performance Assessment of a Semi-Circular Breakwater through CFD Modelling. *Journal of Marine Science and Engineering*. 2020; 8(3):226.
https://doi.org/10.3390/jmse8030226

**Chicago/Turabian Style**

Gomes, Ana, José L. S. Pinho, Tiago Valente, José S. Antunes do Carmo, and Arkal V. Hegde. 2020. "Performance Assessment of a Semi-Circular Breakwater through CFD Modelling" *Journal of Marine Science and Engineering* 8, no. 3: 226.
https://doi.org/10.3390/jmse8030226