Design and Analysis of Wind Turbine Blade

Abstract

This paper summarizes the design and analysis of Jet Wind Turbine blades, CATIA is used for design and analysis for model generated by applying boundary condition; this paper also includes specific post processing and life assessment of blade. We take an opportunity to present this report on “Design and Analysis of Jet Wind Turbine Blades” and put before readers some useful information regarding this project. Drawn by list of priorities progress in the design and structural analysis of jet wind turbine blades is reviewed and presented for generating 100-watt power. This article is motivated by the key role of blades in the performance of jet wind turbine. The fundamentals of the associated physics are emphasized. Recent developments and advancements have led to an increase and improvement in blade aerodynamics, stability and reliability. This article is intended as a high-level review of design of the blade environment and current state of structural design to aid further research in developing new and innovative blade technologies.

Introduction

I. INTRODUCTION

A. Wind as an Energy Resource

One of the earliest non-animal sources of power used by man was the wind turbine. Wind turbines have been in documented use for more than 1,000 years. The earliest wind turbine designs were extremely simple; turbines were allowed to rotate at a rate proportional to the velocity of the wind. They were used to pump water, grind grain, cut lumber, and perform a myriad of other tasks. For these purposes, varying speed seldom impacted the effectiveness of the windmill enough to justify the complications of closely controlling rotational speed. Allowing the machines to run at variable speed was in fact highly advantageous as it greatly increased the total energy that could be extracted from the wind. However, in rural India, where the word “electricity” is still a dream, millions of people do not have access to electricity in their homes. In fact, four out of these five people without electricity live in far flung villages and isolated countryside hamlets, some of which are geographically isolated and are often too sparsely populated or have a too low potential electricity demand to justify the extension of the grid. Thus, to provide access to electricity in these rural areas through other means than the extension of the grid, renewable energy like wind power is among the least cost and most feasible solution (Nagendra, 2009). The earliest horizontal-axis windmill to use the principles of aerodynamic lift instead of drag may have been introduced in the twelth century. These horizontal-axis sail turbines were allowed to run at varying speeds, limited only by braking or furling to control their speed during storms. These designs operated throughout Europe and in the Americas into the present century. In the 700 or so years since the first sail- wing turbine, designers discovered many of the key principles of aerodynamics without understanding the physics behind them. It was not until the nineteenth century that these principles began to be clearly understood (Carlin et al., 2001). The cost of wind-generated electric power has dropped substantially. Since 2004, according to some sources, the price in the United States is now lower than the cost of fuel- generated electric power, even without taking externalities into account. In 2005, wind energy cost one-fifth as much as it did in the late 1990s, and that downward trend is expected to continue as larger multi-megawatt turbines are mass-produced. Wind power is growing quickly, at about 38%, up from 25% growth in 2002. Wind power is the fastest growing form of electricity generation on a percentage basis.

 B. Wind Turbine Blades 

Jet turbine surrounds its wind-turbine blades with a shroud that directs air through the blades and speeds it up, which increases power production. The new design generates as much power as a conventional wind turbine with blades twice as big in diameter. The smaller blade size and other factors allow the new turbines to be packed closer together than conventional turbines, increasing the amount of power that can be generated per acre of land. The idea of enshrouding wind-turbine blades isn’t new. But earlier designs were too big to be practical, or they didn’t perform well, in part because the blades had to be very closely aligned to the direction of the wind— within three or four degrees (Douglas et al., 2011). This turbine design surrounds its wind- turbine blades with a shroud that directs air through the blades and speeds it up, which increases power production. The shroud concept is based on the same principles as a high bypass jet engine design that is used by all commercial jet aircraft engines to reduce noise and significantly improve efficiency. The new design generates as much power as a conventional wind turbine with blades twice as big in diameter.

The smaller blade size and other factors allow the new turbines to be packed closer together in the field compared to conventional turbines, increasing the amount of power that can be generated per acre of land. As air approaches, it first encounters a set of fixed blades, called the stator which are common in jet and steam turbines designs used in power generation, which redirect the air onto a set of movable blades, called the rotor. The air turns the rotor and emerges on the other side, moving more slowly now than the air flowing outside the turbine. The shroud is shaped so that it guides this relatively fast-moving outside air into the area just behind the rotors. The fast- moving air speeds up the slow-moving air, creating an area of low pressure behind the turbine blades that sucks more air through them. We are designing Jet wind turbine blades for generating 100 watt power and to be made simple and small, giving it the ability to handle high wind velocities due to its effectiveness to handle off axis flow and turbulence (William, 2010).

C. Design and Calculation

We are designing Wind Turbine blades for 100 Watt electricity production.

D. Annual Energy Requirement for a Single Home

The energy consumed by a single home in rural area is,

II. MATERIAL SELECTION

The proper selection of material for the different part of a machine is the main objective in the fabrication of machine. For a design engineer it is must that he be familiar with the effect, which the manufacturing process and heat treatment have on the properties of materials. The Choice of material for engineering purposes depends upon the following factors:

1. Availability of the materials.
2. Suitability of materials for the working condition in service.
3. The cost of materials.
4. Physical and chemical properties of material.
5. Mechanical properties of material.

With this background, for small wind turbine it is better to use wood as a blade material (Tom, 1996).

A. Drawing of Blades in CATIA

With the help of above calculation for blades we draw blade in CATIA. Some snapshot of these blades is shown in following Figures 2 and 3:

III. RESULT OF ANALYSIS

The aim of structural analysis is to evaluate the external reactions, the deformed shape and internal stresses in the structure. If this can be accomplished by equations of equilibrium, then such structures are known as determinate structures. However, in many structures it is not possible to determine either reactions or internal stresses or both using equilibrium equations alone. Such structures are known as the statically indeterminate structures.

The indeterminacy in a structure may be external, internal or both. A structure is said to be externally indeterminate if the number of reactions exceeds the number of equilibrium equations (Rossiter, 2006).

IV. RESULTS AND DISCUSSION

In the Jet W ind Turbine when air is approached to stator, it acts as a nozzle that the velocity of wind increases and pressure decreases. Due to this, velocity of airfoil increases rotor spins and produce much power and decreasing pressure results in suction of wind. While comparing JWT with conventional wind turbine due to stator, velocity of the air is increase from 3 m/s to 5 m/s. Average wind velocity is 3 m/s in Chikhli Buldana (M.H) observed by reading.

The velocity is directly proportional to the power, so velocity of wind increases results, and increase in power.

Average wind speed

= (2.96 + 2.53 + 3.36 + 3.3 + 2.7)/5

= 2.97 m/s

Aspect ratio L/C is 5 so chord length becomes 0.54 m while comparing the Radius length and chord length of the conventional blade with jet wind turbine blade.

It is observed that Radius of the rotor and chord length of the conventional blade is 2.16 times greater than jet wind turbine blade. So material, floor space area is reduces and due to all above mentioned parameters efficiency increases due to JWT Blade. Structural design of JW T blades is as important as their aerodynamic design. The dynamic structural loads which a rotor will experience play the major role in determining the lifetime of the rotor. Obviously, aerodynamic loads are a major source of loading and must be well understood before the structural response can be accurately determined and also the blade geometry parameters are required for dynamic load analysis of wind turbine rotors.

So such a study on the dynamic load analysis of JWT blades might also use the outputs of design theory.

Conclusion

As the electricity is need of world also it is very important thing of our day to day life and wind is the cost-free source of energy. The concept of Jet Wind Turbine is more efficient than the conventional wind turbine and produces 3 to 4 times more power. The efficiency of Jet Wind Turbine is increases due to its aerodynamic blades shape along with stator that guides wind to increases the velocity and decrease the pressure to generate power. This JW T blade design process is simple and adequate to reduce the material and utilizes less space area as compare to conventional wind turbine. We suggested that this blade design theory is very useful to produce power at minimum cost and more effectively.

References

[1] Carlin P W, Laxson A S and Muljadi E B (2001), “The History and State of the Art of Variable-Speed W ind Turbine Technology”, February, Presented at the National Renewable Energy Laboratory, Colorado. [2] Douglas S Cairns, Trey Riddle and Jared Nelson (2011), “Wind Turbine Composite Blade Manufacturing”, February, Presented at the Sandia National Laboratories. [3] Grant Ingram (2011), “Wind Turbine Blade Analysis Using the Blade Element Momentum Method”, Version 1.1, October 18. [4] Modi P N and Seth S M (2002), “Hydraulics & Fluid Mechanics”, Standard Book House, pp. 824-831. [5] Nagendra Gopal K V (2009), “The Bulletin of The Energy Forum”, March 4, Presented at the Energy Forum of IIT Madras, Department of Aerospace Engineering. [6] Rossiter D G (2006), “An Introduction to Statistical Analysis”, January 9, Department of Earth Systems Analysis. [7] Tom Ritchey (1996), “Materials and Properties”, Systems Research, Vol. 8, No. 4, pp. 21-41. [8] William J Bierbower (2010), “Breakthrough High Efficiency Shrouded Wind Turbine”, Advanced Research Projects Agency – Energy, January 14, US Department of Energy.

Copyright

Copyright © 2022 Rahul Vaidhye, Prof Ritesh Banapurkar, Pravin Vasram Jadhav. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.