# Numerical Investigation of Aerodynamic Performances for NREL 5-MW Offshore Wind Turbine

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## Abstract

**:**

## 1. Introduction

## 2. Materials and Methods

#### 2.1. Aerodynamic Features

#### 2.2. General Solution Procedure

#### 2.3. Turbine Blade Geometry Modeling

#### 2.4. Mesh Generation

#### 2.5. Aerodynamic Models

## 3. Results

#### 3.1. Mesh Independent Study

#### 3.2. Computational Domain and Boundary Settings

#### 3.3. Model Validation Study

#### 3.4. Wake Vortex Development

#### 3.5. Near Wake Flow Features

#### 3.6. Wind Flow Features near Turbine Blades

#### 3.7. Pressure and Pressure Coefficient Distribution

#### 3.8. Torque and Thrust

#### 3.9. Power Coefficient and Tip Speed Ratio

## 4. Discussion

## Author Contributions

## Funding

## Data Availability Statement

## Conflicts of Interest

## References

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**Figure 3.**Geometry of the NREL 5-MW wind turbine. (

**a**) Airfoils at different cross-sections; (

**b**) Geometry of the turbine blade; (

**c**) Wind turbine geometry.

**Figure 7.**Iso-surfaces of Q = 0.008 under different uniform inlet velocities. (

**a**) U = 5 m/s; (

**b**) U = 9 m/s; (

**c**) U = 11.4 m/s; (

**d**) U = 15 m/s; (

**e**) U = 20 m/s; (

**f**) U = 25 m/s.

**Figure 8.**Downstream wind velocity profile at y/R = 1, 2, 3, 4, 5, 6 under different inlet velocities. (

**a**) U = 5 m/s; (

**b**) U = 11.4 m/s; (

**c**) U = 15 m/s; (

**d**) U = 20 m/s; (

**e**) U = 25 m/s.

**Figure 9.**Limiting streamline on the suction side. (

**a**) U = 5 m/s; (

**b**) U = 11.4 m/s; (

**c**) U = 15 m/s; (

**d**) U = 20 m/s; (

**e**) U = 25 m/s.

**Figure 10.**Limiting streamline on the pressure side. (

**a**) U = 5 m/s; (

**b**) U = 11.4 m/s; (

**c**) U = 15 m/s; (

**d**) U = 20 m/s; (

**e**) U = 25 m/s.

**Figure 11.**Pressure distribution at r/R = 0.3, 0.63, 0.95. (

**a**) U = 5 m/s; (

**b**) U = 8 m/s; (

**c**) U = 20 m/s; (

**d**) U = 25 m/s.

**Figure 12.**Pressure coefficient distribution under U = 5, 8, 15, 20 and 25 m/s. (

**a**) U = 5 m/s; (

**b**) U = 8 m/s; (

**c**) U = 15 m/s; (

**d**) U = 20 m/s; (

**e**) U = 25 m/s.

Simulation Cases | Inlet Velocity (m/s) | Rotational Speed (rpm) |
---|---|---|

case 1 | 4.00 | 7.18 |

case 2 | 5.00 | 7.39 |

case 3 | 8.00 | 9.16 |

case 4 | 9.00 | 10.30 |

case 5 | 11.40 | 11.89 |

case 6 | 15.00 | 12.10 |

case 7 | 20.00 | 12.10 |

case 8 | 25.00 | 12.10 |

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**MDPI and ACS Style**

Zhang, Q.; Wang, X.
Numerical Investigation of Aerodynamic Performances for NREL 5-MW Offshore Wind Turbine. *Wind* **2023**, *3*, 191-212.
https://doi.org/10.3390/wind3020012

**AMA Style**

Zhang Q, Wang X.
Numerical Investigation of Aerodynamic Performances for NREL 5-MW Offshore Wind Turbine. *Wind*. 2023; 3(2):191-212.
https://doi.org/10.3390/wind3020012

**Chicago/Turabian Style**

Zhang, Qiqing, and Xiuling Wang.
2023. "Numerical Investigation of Aerodynamic Performances for NREL 5-MW Offshore Wind Turbine" *Wind* 3, no. 2: 191-212.
https://doi.org/10.3390/wind3020012