# Comparison and Validation of Hydrodynamic Theories for Wave Energy Converter Modelling

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## Abstract

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## 1. Introduction

## 2. Wave Energy Converter Numerical Modelling Theory

#### 2.1. Baseline WEC Modelling Theory

#### 2.1.1. Excitation Force

#### 2.1.2. Hydrostatic Force

#### 2.1.3. Radiation Force

#### 2.1.4. Power Take-Off (PTO) Force

#### 2.1.5. Viscous Drag Force

#### 2.1.6. Cable Force

#### 2.2. Refined Numerical Theories

#### 2.2.1. Weakly Nonlinear Froude-Krylov and Hydrostatic Forces

#### 2.2.2. Body-to-Body Interactions

#### 2.2.3. Dynamic Cables

## 3. Numerical Theory Implementations

#### 3.1. ProteusDS

#### 3.2. WEC-Sim

## 4. Case Study WEC and Field Campaign

#### 4.1. Wave Energy Buoy That Self-Deploys (WEBS)

#### 4.2. Field Campaign Details

#### Wave Reconstruction Methods

## 5. Results and Discussion

#### 5.1. Code-to-Code Comparison

#### 5.2. Code-to-Field Campaign Comparison

## 6. Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 2.**Nonlinear Froude-Krylov and Hydrostatic force meshing dependency. (

**a**) Linear calculations with constant coefficients, (

**b**) Weakly nonlinear calculations with instantaneous surface elevation dependent coefficients.

**Figure 3.**WEC numerical modelling procedure from creating a geometric build to implementating into a time-domain multibody dynamic model.

**Figure 4.**Wave Energy Buoy that Self-deploys WEC device as deployed (tether length not to scale) [47].

**Table 1.**Wave Energy Buoy that Self-deploys Viscous Drag Coefficients for a z-vertical coordinate system.

Rigid Body | C_{Dx} | C_{Dy} | C_{Dz} |
---|---|---|---|

Aft Float | 1 | 1.9 | 1 |

Fore Float | 1 | 1.9 | 1 |

Nacelle | 1 | 1 | 1 |

Heave Plate | 1.4 | 1.4 | 4.5 |

Modelling Scenario | Theory | ||
---|---|---|---|

Weakly Nonlinear (NL) | Body-to-Body Interactions (B2B) | Dynamic Cables (DM) | |

WSM Base | |||

WSM NL | X | ||

WSM B2B | X | ||

WSM B2B and NL | X | X | |

PDS DM | X | ||

PDS DM and NL | X | X |

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**MDPI and ACS Style**

Leary, M.; Rusch, C.; Zhang, Z.; Robertson, B. Comparison and Validation of Hydrodynamic Theories for Wave Energy Converter Modelling. *Energies* **2021**, *14*, 3959.
https://doi.org/10.3390/en14133959

**AMA Style**

Leary M, Rusch C, Zhang Z, Robertson B. Comparison and Validation of Hydrodynamic Theories for Wave Energy Converter Modelling. *Energies*. 2021; 14(13):3959.
https://doi.org/10.3390/en14133959

**Chicago/Turabian Style**

Leary, Matthew, Curtis Rusch, Zhe Zhang, and Bryson Robertson. 2021. "Comparison and Validation of Hydrodynamic Theories for Wave Energy Converter Modelling" *Energies* 14, no. 13: 3959.
https://doi.org/10.3390/en14133959