Vertical Wind Turbine Thesis

7/30/2019 Vertical Wind Turbine Thesis

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Project Team

RMD MDMr.Chandramouli H.R. Mr.Abinandan PatilMr.Mohan patnaik Mr.Raghavendra.Mr.Lokesh kumar. Mr.Srinath.S.

Mr.Srinath.B.V.Mr.LavakumarMr.Narendra

TITLE PA

GE

VERTICAL AXIS WIND TURBINE

Centre Names:Mechanical and ManufacturingEngineering &Automobile and Aircraft design

EngineeringCourse Names:M.Sc (Engg) in Machine Design

& Rotating Machinery Design

FULL TIME 2010 BATCH

GROUP PROJ ECT REPORT

POSTGAD

ENNRNANMAN

MEN

PROGRAMME(PEM

P)

M.S.Ramaiah School of Advanced StudiesPostgraduate Engineering and Management Programmes(PEMP)

#470-P Peenya Industrial Area, 4th

Phase, Bengaluru-560 058Tel; 080 4906 5555, website: www.msrsas.org


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M.S Ramaiah School of Advanced Studies Postgraduate Engineering and Management Programme

Vertical Axis Wind Turbine ii

M.S.RAMAIAH SCHOOL OF ADVANCED STUDIESPostgraduate Engineering and Management ProgrammeCoventry University (UK)

BangaloreCertificate

This is to certify that the M. Sc (Engg.) Project Dissertation titledVertical Wind turbine is a bonafide record of the Group Project work carriedout by H.R.Chandramouli, Mohan Patnaik, Lokesh kumar (RMD) andRaghavendra, Srinath.P., Abhinandan Patil, Srinath.B.Y, Lava kumar &Narendra in partial fulfillment of requirements for the award of M.Sc (Engg.)Degree of Coventry University in Rotating Machinery Design and MachineDesign.

June-2011

Dr. S. Narahari Dr. DeshpandeHOD, A&AD Department A & AD & DepartmentMSRSAS Bangalore MSRSAS Bangalore

Dr. S. R. ShankapalDirector

MSRSAS Bangalore


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Vertical Axis Wind Turbine iii

DDEECCLLAARRAATTIIOONN

Vertical wind turbine

The Group project Dissertation is submitted in partial fulfilment of academicrequirements for M.Sc (Engg) Degree of Coventry University in Rotating Machinery

Design (RMD) and Machinery design (MD). This dissertation is a result of investigation

of the project team. All sections of the text and results, which has been obtained from

other sources, are fully referenced. We understand that cheating and plagiarism

constitute a breach of University regulations and will be dealt with accordingly.

Group 1: Rotating Machinery Design

Sl. No Name of the Student Reg Number

1 H.R.Chandramouli BSB09010001

2 Mohan patnaik BSB0910003

3 Lokesh kumar BSB0910002

Group 2: Machinery Design

Sl. No Name of the Student Reg Number

1 Abhinandan Patil BSB09010001

2 Raghavendra BSB0910006

3 K.Srinath BAB0910003

4 P.V. Srinath BAB0910004

5 Narendra BAB0910005

6 Lavakumar BAB0910002

Date: 30-05-2011


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Vertical Axis Wind Turbine iv

AACCKKNNOOWWLLEEDDGGEEMMEENNTT

We would like to express our sincere thanks to our academic guide Dr. S.

Narahari,. Head of the Department, Automotive & Aircraft engineering for his

relentless patience and guidance throughout every phase of the project. We would like to

acknowledge Dr. Deshpande, faculty ofAutomotive & Aircraft engineering Department

for his valuable guidance throughout the project and as well the procurement of parts for

the project. Their support for exploring, identifying the subject matter and technical

assistance during problem solving have helped in the successful completion of this

project

Our sincere gratitude to Dr. S. Narahari, Course manager, Rotating machinery

design, andDr. N.S.Mahesh, Head of the Department of Mechanical & manufacturing

Engineering and Course manager, Machine Design,MSRSAS,for giving an opportunityto work on this project. He gave us all the useful information and solutions to overcome

the problems we faced. His guidance has been of immense help throughout the project.

We would like to thank the Director of MSRSAS, Dr. S.R. Shankapal for

providing us with all the required facilities and supporting us in the project undertaken.

We would like to thankProf. Q.H. Nagpurwallah and Dr.M.D.Deshpande for

their useful inputs which helped us tremendously. We are also thankful to the staff of

MSRSAS for their help during the course of the project.


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Vertical Axis Wind Turbine v

AABBSSTTRRAACCTT

Vertical Axis Wind Turbines are machines that convert the wind energy into

mechanical energy, which can be diverted to generate electricity. This project is to

develop an aerodynamic simulation model that can be used to understand the dynamics

and structural mechanics of the whole system as well as generating electricity. In this

regard, a turbine consists of important components of which the generator is one of them.

In this team work, we have designed the Vertical axis wind turbine which is

solely based on Savonius type with appropriate blade profile. The design of the blade is

based on the basis of conceptual design which is aerodynamically drag-type devices,

consisting of two blades acts as vanes and partly like an airfoil when they are edge-on

into the wind, creating a small lift effect and thus enhancing efficiency.The blades are

fixed and mounted to the main shaft with the help of bushings and fabricated to the

frame. Frame is welded to the hub which supports all the main rotating components. Hub

also houses bearings at the bottom and another at the top of the main shaft. Rim is fixed

to the outer shaft with the bearing for smooth rotation. The rim is connected to a pulley

with bearing fitted on the pulley shaft, which in turn rotate dynamo for generating the

electricity. This concept is geometrically modelled in CATIA.

Working model of Vertical wind turbine been tested for functionality with

different wind speeds. In order to increase the torque of the turbine with respect to the

wind speed, a smaller pulley is provided with a bearing support and also it is connected

to the dynamo which is directly mounted onto the shaft on the pulley. This type of

Vertical axis turbine is more suitable for house hold or domestic generation of electricity.


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Vertical Axis Wind Turbine vi

LLIISSTT OOFF CCOONNTTEENNTTSS

TITL E PAGE .....................................................................................................................i

DECLARATION.............................................................................................................. ii

DECLARATION............................................................................................................. iii

ACKNOWL EDGEMENT...............................................................................................iv

ABSTRACT.......................................................................................................................v

LIST OF CONTENTS.....................................................................................................vi

LIST OF FIGURES....................................................................................................... vii

List of tables.......................................................................................................................1

Chapter 1...........................................................................................................................2

1. Introduction...................................................................................................................2

1.2 SAVONIUS TURBIBNE[1]

.............................................................................2

1.2.1 Description of the Savonius Rotors

[1]

.........................................................................31.2.2 Blade Design & Manufacturing outline

[4]...................................................................4

1.2.3 Basic Blade Designs ....................................................................................................4

1.2.4 Blade Nomenclature ....................................................................................................5

1.2.5 Blade Specifications[1]

................................................................................................5

1.2.6 Blade Material & Manufacturing.................................................................................6

1.2.7 Blade Profile processing ..............................................................................................6

1.2.8 Blade mounting on the shaft ........................................................................................7

1.3. Vertical Axis Wind Turbine Assembly .........................................................................7

1.3.1 Orthographic Views.....................................................................................................8

1.3.2 Belt design ...................................................................................................................8

1.3.3 Blade: ..........................................................................................................................9

1.4 Methodologies-Design & Drawing.................................................................................9

1.5 Manufacturing & Fabrication process ..........................................................................14

1.6 Design Errors. ...............................................................................................................17

1.7. Improvement identified................................................................................................17

1.8. Estimated Cost of the project .......................................................................................17

Conclusion .......................................................................................................................18

Future Scope....................................................................................................................19

References........................................................................................................................20


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Vertical Axis Wind Turbine vii

LIST OF FIGURES

Fig.1. 1 Savonius wind turbine ...........................................................................................3

Fig.1. 2 Wind flow on the Blade profile .............................................................................3

Fig.1. 3 Basic Blade designs. ..............................................................................................5

Fig.1. 4 Basic Nomenclature...............................................................................................5

Fig.1. 5 Isometric view of blade .........................................................................................6

Fig.1. 6 Blade profiles.........................................................................................................7

Fig.1. 7 Blade mounting positioning on the shaft ...............................................................7

Fig.1. 8 Assembly of Vertical Axis Wind Turbine.............................................................8

Fig.1. 9 Orthographic views of Vertical axis wind turbine.................................................8

Fig.1. 10 Blade profile ........................................................................................................9

Fig.1. 11 Assembly drawings of Lock nut, Bearing & inner shaft ...................................10

Fig.1. 12 Assembly drawing of Hub with the frame.........................................................10

Fig.1. 13 Assembly drawing Hub, lock nut, shaft housing...............................................11

Fig.1. 14 Belt mounting between rim and the pulley........................................................11

Fig.1. 15 Assembly of Hub, Bearing, Rim, lock nut and the pulley with plate support...12

Fig.1. 16 Blade mounting..................................................................................................12

Fig.1. 17 Hub Assembly ...................................................................................................13

Fig.1. 18 Shaft housing assembly .....................................................................................13Fig.1. 19 Assembly of bearing with the shaft ...................................................................14

Fig.1. 20 Overall manufacturing drawings .......................................................................14

Fig.1. 21 Blade and Pulley mounting................................................................................17


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M.S Ramaiah School of Advanced Studies Postgraduate Engineering And Management Programme (PEMP)

Vertical Axis Wind Turbine 1

List of tables

Table 1. 1 ....................................................................................................................................... 5

Table 1. 2 Parts of VAWT............................................................................................................. 8

Table 1. 3 ..................................................................................................................................... 15

Table 1. 4 ..................................................................................................................................... 16


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Chapter 1

1.IntroductionVertical Axis Wind turbines are dimensioned for a nominal running point, i.e. for a

given wind velocity. In order to obtain higher efficiency, two or three-bladed fast running wind

turbines are preferred. Vertical axis wind turbine (VAWT), such as the Savonius rotor, can

extract more energy than fast running wind machines. This idea seems to be in contradiction to

the general literature in the field: the Savonius rotors have an aerodynamic behaviour where the

characteristics of a drag device dominate, which clearly induces a low efficiency. In fact, using

the same intercepted front width of wind L and the same value of the maximal mechanical

stress on the blades, the delivered power of a Savonius rotor is superior to the one of any fast-

running horizontal axis wind turbine.Savonius rotor can theoretically produce energy at lowwind velocities because of its high starting torque and a low angular velocity; it can deliver

electricity under high wind velocities, when fast running wind turbines must generally be

stopped.

1.2 SAVONIUS TURBIBNE [1]

A Savonius wind turbine is an example of a drag-based design. Invented by the Finnish

engineer S. J. Savonius in 1922, it can be made with different types of blades or scoops, e.g.,

buckets, paddles, sails, or oil drums. Looking down on the rotor from above, a two-scoop

machine would look like an S shape in cross section. Savonius wind turbines can and are used

in generating the electricity in the strongest winds without being damaged, they are very quiet,

and they are relatively easy to make. Savonius turbines do not scale well to kW sizes; however

they are useful for small scale domestic electricity generation - especially in locations with

strong turbulent winds.The smaller the turbine blades (from the axis to the tip of the blade), the

faster the rotation and the less torque force developed. This loss in torque then can be recovered

if the blades are made taller in the vertical dimension. Because the design is simpler than

other types of wind turbines, it finds application in low maintenance situations. Design is

simplified because no pointing mechanism is required to allow for shifting wind direction,

unlike horizontal axis turbines.


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1.2.1 Description of the Savonius Rotors [1]

Fig.1. 1 Savonius wind turbine[3]

This is the most efficient Savonius design. It not only has the advantage of air being

deflected twice like the design above, but also that the vanes act partly like an airfoil when they

are edge-on into the wind, creating a small lift effect and thus enhancing efficiency.

Aerodynamical behaviour- Flow characteristics

Fig.1. 2 Wind flow on the Blade profile [2]

When a wind site is chosen to install wind machines in order to produce electricity, it is

expected to extract the maximum possible energy from the wind. Wind speed and power are

mostly forecasted using linearised models which do not count very well for the topographic

effects. In order to interpolate data, measurements at low heights are used. The forecast is

therefore of low accuracy.

Aim

To model and explore the Vertical Wind Turbine of a Savonius rotor (S-rotor) wind

turbine adapted for household/domestic electricity generation

Objectives Evaluate the best blade offset by field testing using a small prototype model.

Produce a turbine capable of generating 10% of the households electricity.

Build a fully functioning 100 Watt household turbine.

To show that using the Savonius turbine for household generation is a viable option.


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Project scope

The wind turbine set up is used to visualize the flow of wind energy which converts

wind in to mechanical energy, which can be diverted to generate electricity.

With the help of this set up homeowners generate their own clean power, thereby

reducing Carbon Dioxide emissions.

Using this set up, it easy to contain the generator and other electrical parts at the ground

level.

1.2.2 Blade Design & Manufacturing outline[4]

Conceptual Design of Rotating Blades

CAD model (using CATIA V5)

Blade material Selection

Manufacturing Process for the Blade

Blade Mounting

Rotor BladesThe Savonius rotor concept never became popular, until recently, probably because of

its low efficiency. However, it has the following advantages over the other conventional wind

turbines:

Low maintenance cost.

Simple and cheap construction;

Acceptance of wind from any direction thus eliminating the need for reorientation;

High starting torque;

Relatively low operating speed (rpm)

Factors involved in construction of Savonius Blades.

The size of the end plates, to which are mounted the buckets, should be about 5% larger

than the diameter of the rotor.

The central shaft should be mounted to the end plates only, and not through the buckets.

An aspect ratio of about 2 is desirable from the economic point of view.

Use only two buckets, as a higher number reduces the efficiency.

The use of augmentation devices such as concentrators or diffusers or combination of

the two result in increased power coefficient

1.2.3 Basic Blade Designs


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Fig.1. 3 Basic Blade designs.[4]

A -It is very strong due to the central shaft, but slightly less efficient than the other two.

However, the extra strength allows the rotor to be supported at one end only.

B- This design is also very simple, and can also be made easily from metal drums or

pipe sections. The design is slightly more efficient than the one above as some of the air

is deflected by the second vane as it exits the first one.

C--This is the most efficient Savonius design. It not only has the advantage of air being

deflected twice like the design above, but also that the vanes act partly like an airfoil

when they are edge-on into the wind, creating a small lift effect and thus enhancing

efficiency.[5]

1.2.4 Blade Nomenclature

Fig.1. 4 Basic Nomenclature[4]

1.2.5 Blade Specifications [1]

Table 1. 1

Sl.No. SweptArea (m2)

WindSpeed(m/s)

AirDensity(kg/m3)

Blade height Blade diameter(2 nos)

1 1m x 0.8m 5.5 m/s 1.23 1 m 0.8m Power output (P) = Au3 =1.742pAu3/T* = Watts (W)

By considering the ambient conditions.

Power wind= 0.647Au3 W


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Where A = area of the turbine, u = wind speed in m/s.

At standard conditions, the power in .8m2 of wind with a wind speed of 5.5 m/s is,

0.647 x 1m x 0.8m x (5.5)3 =86.11 Watts 100 W (approximated power available)[3]

Fig.1. 5 Isometric view of blade[5]

1.2.6 Blade Material & Manufacturing

Material Properties requirements: [1]

Light weight

Corrosion resistant

Good compressive strength

Machinability

Blade material- Aluminum sheet

Thickness of the sheet is 2.5 mm chosen to avoid flattering due to wind speed.

Lightweight and tough hardened aluminum sheet has been used for turbine blade.

1.2.7 Blade Profile processing


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Fig.1. 6 Blade profiles [4]

Thickness of the aluminium sheet is 2.5 mm, is bent in the form of an arc which is

based on the conceptual design of the blade profile.

1.2.8 Blade mounting on the shaft

Fig.1. 7 Blade mounting positioning on the shaft

Sufficient gap has been provided between the two blades during the mounting on the

shaft in order to increase the drag force by wind speed. Then the blade is fitted on the shaft with

the help of bushings.

1.3. Vertical Axis Wind Turbine Assembly


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Table 1. 2 Parts of VAWT

Fig.1. 8 Assembly of Vertical Axis Wind Turbine

1.3.1 Orthographic Views

Fig.1. 9 Orthographic views of Vertical axis wind turbine

1.3.2 Belt design


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Design for the Length of the Belt

Length of the belt (L):

Length of the flat belt (open) = /2*(D+d) + (D-d)2/(4*c) + 2*c

Diameter of Rim = 620 mm; diameter of pulley = 100 mm; Centre to centre distance = 410 mm

Length of the belt = 2110 mm

Considering initial tension of 2% ,length of the belt gets reduced to 2115-

(0.02*2110) = 2068 mm;

Length of the belt = 2068 mm;

Velocity ratio between the Rim & the Pulley

Without slip:

Diameter of rim= DA ; Diameter of pulley= DB

NB = (DA/DB)* NA = (620/100)*60 = 372 rpm;

NB = 372 rpm;

With 2% slip:

NB / NA = (100-s)/100 * (DA/DB);

Velocity ratio = NB / NA =

NB = 365 rpm;

1.3.3 Blade:

Fig.1. 10 Blade profile

1.4 Methodologies-Design & Drawing


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Step 1.

Bearing Cover

A

Lock Nut

HUB

Inner Shaft

Bearing

Bearing

Outer Shaft

Spacer

75.0

750.0

25.0

Structure design

Possibilities for support.

Shaft with one bearing support at the

bottom C frame with a top and bottom

support

Shaft with 2 bearing at top and

bottom and another hallow shaft

rotating over the bearings

Fig.1. 11 Assembly drawings of L ock nut, Bearing & inner shaft

Step 2.

Frame to HubWelding

HUB

75.0

750.0

25.0

0.02A

ABase:

Is a square frame of L angle or box

structure of 750 Sq.

A hub is welded to the frame at the centre,

with a perpendicularity of 0.02mm,

The hub will have a bore to suit the inner

shaft diameter, this is a transition fit with a

clearance of 0.1 mm.

Structure design

Fig.1. 12 Assembly drawing of Hub with the frame

Step 3.


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Inner Shaft

Is a Hallow pipe, in the bottom the shaft is turned to

3 steps,

1 to suit the bearing ID

2 to suit the hub IB

3 there is a threaded portion in the end for a lock nut

to lock in position.

Structure design

A

HU B

Lock Nut

Inner Shaft

75.0

750.0

25.0

Outer Shaft

Is a Hallow pipe, with two

bearing seating's on top and

bottom this is the only support

for the shaft, and it revolves

freely on the inner shaft

Fig.1. 13 Assembly drawing Hub, lock nut, shaft housing

Step 4. Mounting of the belt between Rim & the pulley

75.0

750.0

25.0

Smaller Pulley

Mounting Plate

Shim

0.02A

A

Larger Pulley

Belt

Outer shaft tocycle rim welding Belt Drive

Lager Pulley is welded to the outer shat with a

concentricity of 0.05mm

Then smaller pulley is mounted on the mounting plate,

Shims are used for the adjustment of the centre height

and tensioning.

A flat belt is used for connection

Fig.1. 14 Belt mounting between rim and the pulley

Step 5. Assembly of shaft, with Rim, Bearing & lock nut


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HUB

Larger Pulley

Bearing

Bearing

Outer Shaft

Spacer

75.0

750.0

25.0

9.0

Smaller Pulley

Mounting Plate

Shim

Belt

Bearing Cover

0. 02A

A

L-PlateFrameLock Nut

Inner Shaft

Fig.1. 15 Assembly of Hub, Bearing, Rim, lock nut and the pulley with plate support

Step 6 : Blade mounting

126Typ 1250.0

225.0

225.0

225.0

225.0

12M6

50.0

225.0

Fig.1. 16 Blade mounting


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Step 7: Assembly of hub

24.00

24.00

28.00

65.00

50.0

50.0

200.0

0.000.02

0.000.02

A

0.02 A

0.0

2

A

Hub:

Material is mild steel,

The bore of 24 has a close

tolerance of - 0.02,

The top face must have a

perpendicularity of 0.02 with

respect to the bore.

There is relief in between to

reduce the are of contact,

The top bore must be concentric

to the bottom bore by 0.02mm

Fig.1. 17 Hub Assembly

Step 8: Assembly of shaft housing with the main shaft

M24.00X 1.5

16.00

25.00

25.00

1300

25.0

225.0

9.0

9.0

6

28.00

To suitBearing

ID 25

A

0.02 A

0.0

2

A

0.0

2

A

24.00

0-0.02

To suit withlock nut

Manufacturing drawings

Inside shaft:

Material is mild steel,

The overall OD is maintained as 28 mm

Bottom there are threads to suit lock nut and is

maintained as M24 X 1.5

There is a dia of 24 to suit the hub and there is a

tolerance of 0.02

Then there is bearing seating to suit bearing ID of 25

mm, the perpendicularity has to be maintained

Towards the other end there is a bearing seating for

25mm the concentricity w.r.t to other bearing seating

and perpendicularity has to be maintained

Fig.1. 18 Shaft housing assembly


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Step 1:

Table 1. 3

Parts Lathe

Machine

Milling

Machine

Drilling/

Tapping

Welding Assembly

Hub Turning to

the required

size.

Drilling,

Reaming.

Lock Nut Turning to

the required

Dimension.

Milling of

slots.

Bushes Turning Welding

of bushes

for blade

mounting

Hub to Frame Welding

of Hub to

the frame.

Pulley, I-Plates

For Dynamo

Turning for

making

pulley

Milling for

I-plates.

Drilling for

pulley,I-

plates.


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Step 2:

Table 1. 4

Parts Lathe

Machine

Milling Welding Assembly

Hub Positioningof the hub

Frame Supporting ribsto frame

Bushes Setting bushesfor Blade

mounting

Shaft to Frame Shaft mountingto the Hub and

Frame

Lock nut to shaft Lock nut to theinner shaft.


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1.6 Design Errors.

There was a design error in the belt drive system that was identified at the assembly

stage, there was no bearing support provided at the smaller pulley connected to the

dynamo(highlighted in red), and the smaller pulley was directly mounted onto the dynamo

shaft, due to the belt forces the shaft of the dynamo was getting bent and the alignment of the

smaller puller w.r.t to the larger pulley (cycle rim) could not be achieved and the belt used to

get slipped during the operation of the turbine,

Fig.1. 21 Blade and Pulley mounting

1.7. Improvement identified

The pulley has to be supported with a bearing support and the shaft of the dynamo is

screwed onto the pulley, so that the load acting on the pulley is transferred to the bearing and no

load is transferred to the dynamo shaft also the alignment or the parallelism of the smaller

pulley with respect to the larger pulley can also be achieved.

1.8. Estimated Cost of the project

o Material cost: Rs 6500.00

o Machining Cost: Rs 6150.00

o Fabrication Cost: Rs 7300.00

o Miscellaneous: Rs 550.00

o Total =Rs. 20,500


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Conclusion

The development of Vertical Axis Wind Turbine gave us experience in the design,

fabrication and field testing. Savonius turbines are one of the simplest turbines.

Aerodynamically, they are drag-type devices, whit such large devices it is quite feasible to have

adequate control systems for starting and controlling the system. In India, however, the mean

wind speeds are generally so low that it is unlikely that wind power can be economically

converted to electric power for grid augmentation. The most practical use for wind power is

likely to be direct water pumping for drinking water and minor irrigation purposes. The water

pumping application generally implies high starting torque and low control costs. Hence it

appears at least from general survey that Savonius turbines arc not likely to be of much use in

the Indian context.


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Future Scope

The first generation household turbine which has been manufactured appears to be rather

large and heavy for the purpose of fixing it to the roof or chimney of a domestic property.

However, this design would be suitable for commercial buildings. With some modifications to

the frame, this type of windmill could feasibly be used with the home in mind. Many good

features of this design were seen, namely: reliability; it is easy to manufacture; has no yaw

mechanism; is of a low cost; and has self starting availability. Furthermore the build process has

highlighted several improvements which are to be implemented by the author in the

development of the next generation of household turbine. These enhancements are listed below.

Produce a more compact/lighter wind turbine for easy transportation.

Use a telescopic metal frame for reduced weight and size.

Use a permanent magnet generator or produce a custom made generator.

Improve the aesthetic appeal by using clear blades.

Small Savonius wind turbines can be used as advertising signs where the rotation helps

to draw attention to the item advertised. They sometimes feature a simple two-frame

animation.

Connect the wind turbine directly to the mains within the home.

Use an inverter to adjust the 12 volt DC to mains supply (240 volt AC) thus opening up

more household applications.

Increase the gear ratio so that the turbine has the potential to spin faster.

Add a braking mechanism to stop the rotor in gale force winds. [2]


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RReeffeerreenncceess

[Referring a Book]

[1] Joachim Peinke, Peter Schaumannand Stephan Barth (Eds.) Wind Energy Institute of

Physics, 26111 Oldenburg, University of Hannover, Institute for Steel Construction.

Appelstrasse 30167 Hannover

[Referring a Journal paper]

[2] Dr. Gary L. Johnson, Wind Energy Systems November by 21, 2001

[Referring a Thesis]

[3] P.N. SHANKAR,Development of vertical axis wind turbines, National Aeronautical

Laboratory, Bangalore 560 017

[Referring a website]

[4] Unknown- http://wind.nrel.gov/public/library/11045.pdf Retrieved on 25-05-2011

[Software]

[5] www.catia.com

Vertical Wind Turbine Thesis

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