1 of 35

NEW DESIGNS OF VAWT AND COMPARING IT TO ITS TRADITIONAL TYPES

Wind turbines

2 of 35

PRESENTED BY

Philobater saad

Mohamed nader

Adham afifi

Mohaned Rostom

Karim medhat

- Dr el araby el morsy

2

Supervised BY

- DR. Rola Afifi

3 of 35

CLASSIFICATION AND TYPES:

THEORY OF OPERATION

DESIGN& COMPONENTS

PERFORMANCE

Pitch Deck

3

20XX

ADVANTAGES& DISADVANTAGES

4 of 35

WORKING PRINCIPLE

Wind turbines work on a simple principle: instead of using electricity to make wind like a fan wind turbines use wind to make electricity converting wind power into mechanical energy).

4

5 of 35

CLASSIFICATION AND TYPES:

WIND TURBINES CAN BE CLASSIFIED INTO DIFFERENT GROUPS ACCORDING TO:

AXIS OF ORIENTATION :

HORIZONTAL AXIS AND VERTICAL AXIS.

NUMBER OF BLADES:

SINGLE BLADED, TWO BLADED, THREE BLADED AND MULTIBLADED.

POSITION OF ROTOR:

UPWIND TYPE ROTOR AND DOWNWIND TYPE ROTOR.

Pitch Deck

5

20XX

6 of 35

INTRODUCTION

Definition Of Wind Harvesting:

Wind harvesting is the process in which the wind is used to generate mechanical power or electricity. Wind turbines convert the kinetic energy in the wind into mechanical power.

6

7 of 35

HOW WIND TURBINE WORK

A wind turbine turns wind energy into electricity using the aerodynamic force from the rotor blades, which work like an airplane wing or helicopter rotor blade. When wind flows across the blade, the air pressure on one side of the blade decreases. The difference in air pressure across the two sides of the blade creates both lift and drag. The force of the lift is stronger than the drag and this causes the rotor to spin. The rotor connects to the generator, either directly (if it's a direct drive turbine) or through a shaft and a series of gears (a gearbox) that speed up the rotation and allow for a physically smaller generator. This translation of aerodynamic force to rotation of a generator creates electricity

7

8 of 35

INTRODUCTIONHORZIONTAL VS VERTICAL AXIS WIND TURBINES :

Pitch Deck

8

20XX

9 of 35

TYPES OF VAWT

$3B

$2B

$1B

SAVONIOUS

DARRIEUS

9

vawt

10 of 35

HOW WIND TURBINE WORK

A wind turbine turns wind energy into electricity using the aerodynamic force from the rotor blades, which work like an airplane wing or helicopter rotor blade. When wind flows across the blade, the air pressure on one side of the blade decreases. The difference in air pressure across the two sides of the blade creates both lift and drag. The force of the lift is stronger than the drag and this causes the rotor to spin. The rotor connects to the generator, either directly (if it's a direct drive turbine) or through a shaft and a series of gears (a gearbox) that speed up the rotation and allow for a physically smaller generator. This translation of aerodynamic force to rotation of a generator creates electricity

10

11 of 35

���INTRODUCTION

Introduction:

  • The Savonius wind turbine is a simple vertical axis wind machine invented by Sigurd J. Savonius in 1922.
  • Savonius rotor (S-type) is a type of VAWT and its function depends on the drag force

Pitch Deck

11

20XX

SAVONIUS WIND TURBINE:

12 of 35

SAVONIOUS BLADES

12

13 of 35

SAVONIOUS WIND TURBINE (CON.)

WORKING PROCESS:

  • In a given wind stream, the drag force experienced by the Concave half would be higher than that of the Convex half (due to the higher drag coefficient of the concave side).
  • It is this difference in drag force that spins the rotor to develop mechanical power.

13

14 of 35

HOW A WIND TURBINE WORKS

 

14

15 of 35

PERFORMANCE:

 

24/50

16 of 35

SAVONIOUS TURBINE PERFORMANCE:

Parameters that affect the performance of Savonius wind turbine:

Blades number:

the optimum number of blades is two for the Savonius rotor whether it is single, two or three stage.

Blade shapes:

By modifying the blades shape the aerodynamic properties of the blades can be increased therefore increasing the coefficient of power.

Number of stages:

a single staged rotor gives a Cp = 0.18, a two-staged rotor gives a

Cp = 0.29, while the three-staged rotor Cp of only 0.23.

25/50

17 of 35

SAVONIOUS TURBINE PERFORMANCE (CON.):

Parameters that affect the performance of Savonius wind turbine:

Aspect Ratio:

the ratio between blade length and rotor radius, generally the use of ARs within the range of 1.5–2.0 set good results on the performance.

Overlap ratio:

the ratio of the diameter of the rotor blade to the distance which the blades overlap, the optimal value of overlap ratio is in the range of 0.1 to 0.15.

26/50

18 of 35

APPLICATIONS:

Savonius turbines are used whenever cost or reliability is much more important than efficiency for this reason it is used in:

  1. Most anemometers (as efficiency is irrelevant to the application of measuring wind speed).
  2. Much larger Savonius turbines have been used to generate electric power on deep-water buoys.
  3. the Flettner ventilator, which is commonly seen on the roofs of vans and buses and is used as a cooling device. It uses the Savonius wind turbine to drive an extractor fan.

27/50

19 of 35

DARRIEUS WIND TURBINE:

Introduction:

An alternate name of Darrieus Wind Turbine is an Eggbeater turbine. This kind of turbine was invented in the year 1931 by Georges Darrieus. A Darrieus machine is a low torque and high-speed device used to generate AC (alternating current). Generally, Darrieus requires physical push so some exterior power source is used to start rotating because the initial torque is extremely low. This machine consists of two blades that are vertically oriented and rotating around a perpendicular shaft.

28/50

20 of 35

THEORY OF OPERATION:

  • This turbine not self starting it requires motor which is powered to starting the rotate ,as soon as it arrived to sufficient speed “the wind across airfoils starts to produce torque
  • Low torque ?
  • The initial torque extremely low so we need motor to starting torque
  • Two blades rotating around a perpendicular shaft

31/50

21 of 35

TYPES OF DARRIEUS:

29/50

22 of 35

SWEEP AREA:

To calculate the wind power, we need to find out the swept region of the wind turbine based on the following equations:

A = D * H

Where

H: is the turbine’s height

D: is the diameter of the blade

32/50

23 of 35

WIND POWER:

The available power of wind can be calculated like the following.

If we know the sweep area, we can discover the accessible wind power based on the following formula.

Pwind = 0.5 * ρ * v³ * A

Where:

A: is the sweep area

ρ: is the density of air

V: is the wind speed

Pwind: is the accessible wind power.

33/50

24 of 35

EFFICIENCY & POWER OUTPUT

The turbine efficiency can be calculated like the following:

μ = (1 – k) * (1 – kₑ) * (1 – ke,t) *(1 – kt) * (1 – kw) * C

Where:

C:  is the turbine efficiency and is typically  between 30-40%

kw: is the wake of losses

kₑ: is the electrical losses of the wind turbine

ke,t: is the electrical losses of transmission to the grid

kt: is the % of the time out of order because of failure

μ: is the real efficiency

To find out the power of the wind turbine, simply multiply the efficiency through the available wind power

Poutput = μ * Pwind

34/50

25 of 35

EFFICIENCY:

35/50

  • On average, the efficiency of a horizontal axis wind turbine lays between 40 to 50 %, meaning the turbine is able to convert 40% to 50 % of the kinetic energy it receives into actual electrical power. On the other hand, a Savonius vertical axis wind turbine has an average efficiency of 10 to 17 %, while the Darrieus vertical axis wind turbine reaches 30 to 40 

26 of 35

APPLICATIONS:

Agriculture

Grinding grain

pumping water

36/50

27 of 35

DESIGN AND COMPONENTS:

The darrieus turbine is composed of:

  • airflow sensor
  • speed sensor
  • battery voltage monitoring and
  • microcontroller and WIFI used for IOT

37/50

28 of 35

DESIGN AND COMPONENTS:

The darrieus turbine is composed of:

  1. airflow sensor
  2. speed sensor
  3. battery voltage monitoring and
  4. microcontroller and WIFI used for IOT

37/50

29 of 35

WIND POWER:

47/50

30 of 35

ADVANTAGES AND DISADVANTAGES:

Advantages

The rotor can take wind from every direction

Ease of maintenance

low maintenance cost.

virtually silent operation

Easily integrates into buildings

Disadvantages

Difficult start.

low efficiency.

Lower Available Wind Speed

They have a low starting torque and may need energy to begin turning.

40/50

31 of 35

Pitch Deck

31

20XX

32 of 35

Pitch Deck

32

20XX

33 of 35

SUMMARY

What Makes Vertical-Axis Wind Turbines Better is that for a vertical-axis wind turbine, the shaft it set transverse to the wind and its main components are found at the turbine’s base. This arrangement enables the gearbox and generator to be positioned near the ground

As a result, maintenance/servicing and repair is much easier compared to horizontal-axis turbines where the key components are located high atop a tall tower. This reduces not just the costs but also the environmental impact

Pitch Deck

33

20XX

34 of 35

REFERENCES:

  1. https://windexchange.energy.gov/what-is-wind , accessed at 10/10/20222. https://www.energy.gov/eere/wind/how-do-wind-turbines-work, accessed at 10/10/20223. https://www.eia.gov/energyexplained/wind/history-of-wind-power.php , accessed at 10/10/20224.
  2. https://www.conserve-energy-future.com/comparison-of-horizontal-and-vertical-axis-wind-turbines.php , accessed at 10/10/20225.
  3. https://www.sciencedirect.com/topics/engineering/horizontal-axis-wind-turbine , accessed at 10/10/20226.
  4. https://www.elprocus.com/vertical-axis-wind-turbine/ , accessed at 10/10/20227.
  5. https://www.sciencedirect.com/topics/engineering/savonius-wind-turbine , accessed at 10/10/20228.
  6. https://www.sciencedirect.com/topics/engineering/vertical-axis-wind-turbine , accessed at 10/10/20229.
  7. https://en.wikipedia.org/wiki/Savonius_wind_turbine , accessed at 10/10/202210.
  8. https://www.3ciencias.com/wp-content/uploads/2020/11/art-4-ed-esp-oct-2020-3c-tecno-1.pdf , accessed at 10/10/202212.
  9. https://www.irjet.net/archives/V8/i3/IRJET-V8I3188.pdf , accessed at 10/10/202213.
  10. https://arborwind.com/vertical-axis-wind-turbines/#:~:text=What%20is%20a%20Vertical%20Axis,which%20the%20vertical%20blades%20sit ,accessed at 10/10/202214.
  11. https://blog.arcadia.com/vertical-axis-wind-turbines-advantages-disadvantages/ ,accessed at 10/10/202216.
  12. https://www.windturbinetechnicians.net/vertical-axis-wind-turbine/ , accessed at 10/10/202217.
  13. https://vortexbladeless.com/objections-and-vortexs-limitations , accessed at 10/10/202218.
  14. https://www.researchgate.net/publication/317350183_Efficiency_comparison_of_horizontal_axis_wind_turbines_and_bladeless_turbines , accessed at 10/10/202219.
  15. https://www.windturbinetechnicians.net/vertical-axis-wind-turbine/ , accessed at 10/10/2022

50/50

35 of 35

Pitch Deck

35

20XX