VAWT Presentation

M. S. Ramaiah School of Advanced Studies 1

GROUP PROJECT PRESENTATION

Group:- RMD & MD (PEMP FT - 10)

Title:-VERTICAL WIND TURBINE

Project leaders:- Dr.Narahari,HOD, A&AE Department

Dr.N.S.Mahesh, HOD, MME DepartmentProject group:-RMD MD

Mr.Chandramouli H.R. Mr.Lava kumar

Mr.Mohan patnaik Mr.Srinath.k.

Mr.Lokesh kumar. Mr.Abinandan patil

Mr.Srinath.P.V

Mr.Raghavendra

Mr.Narendra.


Aim ,Objective and Scope of the project.

Introduction

Methodology adopted

Design and Fabrication

Conclusion

CONTENTS


AIM & OBJECTIVE

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 5%~10% of the household’s electricity. To show that using the Savonius turbine for household generation is a viable option.


Objectives

• To study the Savonius generator which relies solely on drag to produce a force that turns the turbine shaft.

To understand the fundamentals of turbine design, and to evaluate the best blade profile.

To study the generation of electricity.

To study the occurrence of self –starting in low wind speeds.

To calculate the performance of the wind machine

To study the overall structure of the turbine


Scope of the project

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

It helps in putting the wind to work, the household electricity bill should be decreased.

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


INTRODUCTION

Vertical-axis wind turbines are a type of wind turbine where the main rotor shaft is set vertically.

The vertical design means that blades pushed by the wind will turn the shaft to which they are connected.

Fig.1 Vertical Axis wind turbine (Savonius type)


SAVONIUS TURBINE

The Savonius is a drag-type VAWT.

Savonius wind turbine cannot rotate faster than the speed of the wind.

Savonius type vertical axis wind turbines turn slowly but generate a high torque.

Savonius turbines are suitable for small scale domestic electricity generation -especially in locations with strong turbulent winds.


Blade Design & Manufacturing outline

Conceptual Design of Rotating Blades

CAD model (using CATIA V5)

Blade material Selection

Manufacturing Process for the Blade

Blade Mounting


Rotor Blades

The 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:

• Simple and cheap construction;

• Acceptance of wind from any direction thus eliminating the need

for reorientation;

•High starting torque;

•Relatively low operating speed (rpm)


The following are some rules for construction of a Savonius rotor.

•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

Design criteria


Basic Blade Designs

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.

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.

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. Fig. 2 Blade profiles


Conceptual Design

D- Rotor Diameterq- Radius of circular arcp- Straight edge of bladeH- Rotor Heights- End extend

m- Overlap DistanceΨ- Arc angleθ- Rotation angle

Nomenclature-Fig. 3 Blade profiles


Blade Size Calculation

Watts output = Pw = ½ ρAu3 =1.742pAu3/T= Watts (W) Power wind = 0.647Au3 W

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


Blade with dimensions

Fig.4 Blade dimensions in different views


Catia model

Fig.5 Isometric view of blade


Blade Material and Manufacturing

Material Properties requirements:

•Light weight

•Corrosion resistant

•Good compressive strength

• Machinability

Aluminum sheet

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


Process for the blade profile

Arc bending

Arc bending has been done to get the shape what we require for our blade profile.

Fig. 6 Blade profiles


Blade mounting on the shaft

Some gap has been given between outer shaft and blade to make turbine more efficient. Because from this passage air can pass and hit the other blade by this combination rpm of the turbine has been increased.

Fig.7 Blade mounting position on the shaft



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


Base:

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


Inner Shaft

Is a Hallow pipe, in the bottom the shaft is turned to 3 steps,1 to suit the bearing ID2 to suit the hub IB3 there is a threaded portion in the end for a lock nut to lock in position.

Structure design

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


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


Assembly



Manufacturing drawings

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



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 maintainedTowards 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



Inside shaft:

Material is mild steel,

The overall OD is maintained as 54 mm

At top end there is bearing seating to suit bearing OD of 42 mm, the perpendicularity has to be maintained.

Towards the other end there is a bearing seating for 42mm the concentricity w.r.t to other bearing seating and perpendicularity has to be maintained




CATIA MODEL OF VAWT

Fig. 8 VAWT assembly


1. FRAME 1NO.2. LOCK NUT 2NOS.3. HUB – WIND TURBINE 1 NO.4. RIM 1 NO.5. BOTTOM BEARING 1 NO.6. INTERNAL SHAFT 1 NO.7. OUTSIDE TUBE 1 NO.8. TOP BEARING 1 NO.9. SUPPORTING PLATE PULLEY 1 NO.10.SPACER 1 NO.11.PULLEY WITH DYNAMO 1 NO.12.DYNAMO MOUNTING PLATE 1 NO.13.SPACER FOR DYNAMO 1 NO.14.BELT 1 NO.15.BLADE 2 NOS.16.BUSHING 10 NOS.

BILL OF QUANTITY


DETAILED VIEW OF VAWT

Fig. 9 Orthographic views


WIND TURBINE MODEL PROCEDURE

Based On Conceptual Design Model As Been Created Part By Part Using CATIA.Applied the material properties for all part.Assembly has done as per fabricating procedure.Detailing Is Done For Each PartsDimensional And Geometric Constraints Are Done For Sketches and modelAssembly Constrains Are Done As Per Simulation requirement and arrested the degree of freedom


Length of the Belt

Length of the belt (L):

Length of the flat belt (open) = π/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

Therefore length of the belt = 2110 mm

Considering initial tension of 2% ,length of the belt gets reduced to 2115- (0.02*2110) = 2068 mm;

Therefore length of the belt = 2068 mm;


Velocity ratio

• 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= 6.1;

NB = 365 rpm;


Kinematic simulation using Adams


Joints


Simulation video


Simulation video (top view)


As per the design requirement we have chosen following material for different parts.

•For inner shaft, outer shaft, hub, pre load cap for bearing, Dynamo assembly parts, blade supporting shaft- Mild Steel.Because its very cheap and most versatile. High strength & malleability, so it is soft. This means it can be easily machined & welded.

•Blade- Al.

•Belt- Nylon.

•The machines which were used for manufacturing the parts are milling, drilling, lathe and laser cutting machine.

Fabrication


Welding

Isometric view of blade in catia

MIG welding (Metal Inert Gas):

•The gas which is used is Argon (Ar)•MIG welder uses electrical current to raise the temperature of the base metal and fuse the filler metal together in an electrical arc.•Temperature range is 3000- 6000 C

Advantages:•Very smooth welding.•Faster & quicker process.•Economical & easy to use.


Blade dimensions in different views

Machined parts

Hub Dynamo assembly parts

Lock nut Nylon belt


Positioning of Hub Welding of Hub To the frame

Supporting ribs Setting of bushes for Blade mounting


Welding of bushes For blade mounting

Shaft mounting in the Hub

Lock nut for Inner shaft


• For achieving the concentricity and accuracy of shafts.

• Slots are made for the purpose of reducing the weight of the rim.

Primary design of rim Sheet metal Modified assembly

of rim

Modification done in fabrication


Estimated Project Cost

•Material cost: Rs 6500/-

•Machining Cost: Rs 6150/-

•Fabrication Cost: Rs 7300/-

•Miscellaneous: Rs 550/-


• THANK YOU

VAWT Presentation

Documents

savonius wind turbine

type of wind turbine

projectthe wind turbine

wind machine

conventional wind turbines

kinetic energy of wind

flow of wind energy

savonius turbines