# Numerical and Computational Analysis of a New Vertical Axis Wind Turbine, Named KIONAS

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## Abstract

**:**

## 1. Introduction

## 2. Numerical Computation

#### 2.1. Mathematical Study

#### 2.2. Computational Fluid Dynamics Study

## 3. Results and Discussion

#### 3.1. Mathematical Results

#### 3.2. Computational Fluid Dynamics Results

## 4. Conclusions

## Acknowledgments

## Author Contributions

## Conflicts of Interest

## References

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**Figure 1.**(

**a**) The front view; (

**b**) the top view of the basic geometry of a three-stage wind turbine KIONAS. Units in mm.

**Figure 2.**Analysis of the half top view of the stator, in order to calculate the magnitude of velocity inlet and the resultant velocity at various stator sections.

**Figure 4.**Total power at each blade’s position for wind velocity (

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

**b**) 10 m/s for various numbers of blades.

**Figure 5.**Total power at each blade’s position, for eleven rotor blades made of aluminum or galvanized sheet metal.

**Figure 6.**Total power at each blade’s position for wind velocity 5 m/s, various numbers of blades and rotor’s diameter (

**a**) 1.37 m; (

**b**) 2.02 m.

**Figure 7.**Total power at each blade’s position for eleven rotor blades with 25° inclination and without inclination and wind velocity (

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

**b**) 10 m/s.

**Figure 12.**Static pressure (Pa) distribution (

**a**) on the contested surface; (

**b**) on the non-contested surface of a one-stage KIONAS, rotor blade angle of 45 degrees and stator with flat guide vanes.

**Figure 13.**Static pressure (Pa) distribution (

**a**) on the contested surface; (

**b**) on the non-contested surface of one-stage KIONAS, rotor blade angle of 25 degrees and stator with flat guide vanes.

**Figure 14.**Static pressure (Pa) distribution (

**a**) on the contested surface; (

**b**) on the non-contested surface of one-stage KIONAS, rotor blade angle of 25 degrees and stator with curved guide vanes.

**Figure 15.**Static pressure (Pa) distribution (

**a**) on the contested surface; (

**b**) on the non-contested surface of two-stage KIONAS, rotor blade angle of 25° and stator with curved guide vanes.

**Figure 16.**(

**a**) Velocity vectors (m/s); (

**b**) contours of velocity (m/s) on xy plane and the center of the rotor for two-stage KIONAS, rotor blade angle of 25° and stator with curved guide vanes.

**Figure 17.**(

**a**) Velocity vectors (m/s); (

**b**) contours of velocity (m/s) on xy plane and the center of the rotor for two-stage KIONAS, rotor blade angle of 30° and stator with curved guide vanes.

**Figure 18.**(

**a**) Velocity vectors (m/s); (

**b**) contours of velocity (m/s) on xy plane and the center of the rotor for two-stage KIONAS, rotor blade angle of 35° and stator with curved guide vanes.

**Table 1.**Mean power output in Watts for wind speed of 5 m/s and 10 m/s for various numbers of blades.

Wind Speed u = 5 m/s | Wind Speed u = 10 m/s | |
---|---|---|

2 blades | 32.9 | 263.6 |

3 blades | 42.1 | 336.7 |

4 blades | 50.3 | 402.1 |

5 blades | 57.8 | 462.2 |

6 blades | 64.8 | 440.3 |

7 blades | 71.4 | 571.5 |

8 blades | 77.8 | 622.1 |

9 blades | 83.8 | 670.7 |

10 blades | 89.7 | 717.6 |

11 blades | 95.4 | 762.8 |

d_{rotor} = 0.72 m | d_{rotor} = 1.37 m | d_{rotor} = 2.02 m | |
---|---|---|---|

2 blades | 32.9 | 55.5 | 81.1 |

5 blades | 57.8 | 93.5 | 132.4 |

10 blades | 89.7 | 141.9 | 198.3 |

© 2017 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license ( http://creativecommons.org/licenses/by/4.0/).

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**MDPI and ACS Style**

Douvi, E.; Douvi, D.; Margaris, D.; Drosis, I.
Numerical and Computational Analysis of a New Vertical Axis Wind Turbine, Named KIONAS. *Computation* **2017**, *5*, 8.
https://doi.org/10.3390/computation5010008

**AMA Style**

Douvi E, Douvi D, Margaris D, Drosis I.
Numerical and Computational Analysis of a New Vertical Axis Wind Turbine, Named KIONAS. *Computation*. 2017; 5(1):8.
https://doi.org/10.3390/computation5010008

**Chicago/Turabian Style**

Douvi, Eleni, Dimitra Douvi, Dionissios Margaris, and Ioannis Drosis.
2017. "Numerical and Computational Analysis of a New Vertical Axis Wind Turbine, Named KIONAS" *Computation* 5, no. 1: 8.
https://doi.org/10.3390/computation5010008