savonius wind turbine
DESCRIPTION
Presentation on design and development of a wind turbine blade.TRANSCRIPT
Datta Meghe College of Engineering, Airoli, Navi MumbaiDepartment of Mechanical Engineering
A Seminar on
ANALYSIS AND OPTIMIZATION OF SAVONIUS WIND TURBINE
Under the guidance ofProf. (Dr.) Vilas B. Shinde
Presented by Aditya S. Kasar
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CONTENT
Introduction
Literature Review
Design
CFD Analysis
Conclusion
Future Scope
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CONTENT
Introduction
Literature Review
Design
CFD Analysis
Conclusion
Future Scope
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INTRODUCTION
What is
MOTIVATION BEHIND THE PROJECT?What are the project
AIM &OBJECTIVES?
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MOTIVATION BEHIND THE PROJECT
Depleting conventional natural resources at alarming rate.
Need for developing use of non-conventional energy resources.
Shortage of electricity faced in small towns and villages.
Tap the potential Air Energy available and maximize the power generation economically.
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INTRODUCTION
TYPES OF WIND TURBINE AVAILABLE
FOCUS OF OUR STUDY
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WHY ?INTRODUCTION
It is simple in geometry and construction is cheap
Works at lower wind speeds compared to its counterpart
Works irrespective wind flow direction.
AIM & OBJECTIVES
Study the existing Savonius wind turbine designs.
Analyze the several factors determining the power output.
Modify the design to increase the efficiency of existing Savonius wind turbine.
Promote the use of Savonius wind turbines to supplement the power supply in small towns and villages
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INTRODUCTION
CONTENT
Introduction
Literature Review
Design
CFD Analysis
Conclusion
Future Scope
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LITERATURE REVIEW
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Sr. No.
Author [Ref] Findings
1 JL Menet et. al. 2012 [1] The increase of wind speed, causes torque to increase, however this necessarily need not increase the power coefficient.
2 Gupta R. et. al. 2012 [2] The maximum power coefficient of 51% was found where there was no overlap
3 A. Biswas et. al. 2012 [3] Optimum aspect ratio for Savonius rotor was found to be 0.8
4 UK Saha et. al. 2008 [4] Among a comparison between the semicircular and the twisted ones, the semicircular model was found to be more efficient than the twisted one
5 Md. Quamrul Islam et. al. 2005 [5]
Maximum torque is generated when blades are at angle of 120o with wind velocity.
CONTENT
Introduction
Literature Review
Design
CFD Analysis
Conclusion
Future Scope
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DESIGN
What are
DESIGN CONSIDERATIONSAnd
DESIGN METHODOLOGY
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3
2
1AvPwind
Power Proportional to (Wind Speed)3
Power Proportional to (Rotor Diameter)2
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Higher Tower
Higher Wind Speed
More Power
Large Rotor Diameter
More Power
OR
DESIGN > DESIGN CONSIDERATIONS
what are the
Critical Parameters
Focus of our study
To analyze existing Savonius rotor design and performance
To modify the design of Savonius rotor
To analyze modified Savonius rotor
To design parts
DESIGN
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DESIGN STEPS
Power (P) watts 42
Velocity of wind (V) m/s 6
Coefficient of power (C p) 0.154
Tip speed ratio (TSR) 0.65
Overlap ratio ( )β 0.15
Inner radius for rotor blade (R) mm 175
Rotor Overlap (a) mm 52.5
Rotor Diameter (D) mm 657.5
Height of Blade (H) mm 1620
Rotor Aspect ratio ( )α 1
Density of air ( ) kg/mρ 3 1.2
Density of PVC kg/m3 1420
Blade thickness (t) mm 5
DESIGN > DESIGN STEPS ANALYSIS OF EXISTING SAVONIUS ROTOR
ACTUAL POWER OBTAINED:
P = 9 watt
P = 21.24 watt
THEORITICAL POWER:p
3C2
1AvPwind
The Power output is much less than expected
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UK Saha , S Thota, D Maity (2008), “Optimum design configuration of Savonius rotor through wind tunnel experiments “, Journal of Wind Engineering and Industrial Aerodynamics 96 (2008)
MODIFICATION OF SAVONIUS ROTOR
Design methodology is as follows:
Determination of Blade Profile
Determination of Overlap Ratio
Determination of Rotor Diameter
Determination of Number of Blades
Selection of Blade Material
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DESIGN > DESIGN STEPS
DETERMINATION OF BLADE PROFILE
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UK Saha (4) “Optimum design configuration of Savonius rotor through wind tunnel experiments”, Journal of Wind Engineering and Industrial Aerodynamics 96 (2008)
Blade Shape: Semi-circular
Blade shape and geometry is kept unchanged since it is found to be efficient compared to other shapes
DESIGN > DESIGN STEPS
DETERMINATION OF OVERLAP RATIO
From the research study we have noted that for a Savonius rotor the optimal value for overlap is zero.
Overlap ratio ( ) = 0β
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Gupta R.(2) “Comparative study of a three bucket Savonius rotor with a combined three bucket Savonius –three bladed Darrieus rotor”, Renewable Energy, (2013)
DESIGN > DESIGN STEPS
DETERMINATION OF ROTOR DIAMETER
Optimum value for aspect ratio (H/D) = 0.8
Keeping height of rotor constant we determine the rotor diameter
D = H / 0.8
D = 1620 / 0.8
D = 2000 mm
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DESIGN > DESIGN STEPS
DETERMINATION OF NUMBER OF BLADES
(air density)ρ 1.2 kg/m3
V (air velocity ) 6 m/s
CD (Drag coefficient ) 2.3
Area exposed for blade 1 0.48 m2
Area exposed for blade 2 0.567 m2
Drag Force on Blades FD = 0.5 x A x x Vρ 2 x CD
Drag Force on Blade 1 FD1 = 23.94 N
Drag Force on Blades 2 FD2 = 14.96 N
23
.94
14
.96
Fnet = 9.25 N
Hence two blades hamper the efficiency
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DESIGN > DESIGN STEPS
UK Saha (4) “Optimum design configuration of Savonius rotor through wind tunnel experiments”, Journal of Wind Engineering and Industrial Aerodynamics 96 (2008)
DETERMINATION OF NUMBER OF BLADES
To overcome drawback, we suggest to increase the number of blades to three.
Research study concluded that maximum drag force is experienced when blades are 120o apart.
120o
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Md. Quamrul Islam et. al. “Proceedings of the International Conference on Mechanical Engineering” 2005 (ICME2005) 28- 30 December 2005, Dhaka, Bangladesh
DESIGN > DESIGN STEPS
SELECTION OF BLADE MATERIAL
Light weight
Complex shapes are easily accomplished
Resistant to corrosion
Resistant to fatigue damage with good damping characteristics
We have selected Fiber Reinforced Plastic (FRP) for blade material
Due to following advantages it offers
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DESIGN > DESIGN STEPS
ANALYSIS OF MODIFIED SAVONIUS ROTOR
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DESIGN > DESIGN STEPS
TSR = Vtip / V
The most important design variables are Tip Speed Ratio (TSR) and Coefficient of Power (Cp)
Vtip = 3.14 x D x N /60
(N) = 33 rpm for wind velocity (V) = 6 m/s [6]
TSR = 0.57
JL Menet (2004), “A double step Savonius rotor for the local generation of electricity: a design study”, Renewable Energy 29 (2004)
Cp = 0.21 Graph for Betz Limit for VAWT [6]
Velocity of wind (U) m/s 6
Rotor Speed (N) rpm 33
Coefficient of Power (Cp) 0.21
Tip speed ratio (TSR) 0.57
Overlap ratio ( )β 0
Rotor Diameter (D) mm 2000
Height of Blade (H) mm 1620
Density of air ( ) kg/mρ 3 1.2
Drag coefficient 2.3
ANALYSIS OF MODIFIED SAVONIUS ROTOR
Mechanical Power of Wind Turbine Pm
P = 2 x 3.14 x N x T / 60
P = 97.26 Watt
Theoretical Power of Wind Turbine Pt
P = 0.5 x A x x Vρ 3 x Cp
P = 88.17 Watt
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DESIGN > DESIGN STEPS
Modified Savonius rotor
Conventional Savonius rotor
Power
Power
BRACKET ARM
Following Bracket arm is designed to support the blades
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DESIGN > DESIGN STEPS
CONTENT
Introduction
Literature Review
Design
CFD Analysis
Conclusion
Future Scope
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The flow analysis for the modified Savonius rotor is done for the range of wind velocity from 2 m/s to 8 m/s
Computational domain is 5m x 5m x 15m
Flow through the Savonius rotor blade, and then exit through the outlet that is set to environmental conditions
CFD ANALYSIS 10/01/2014
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CFD ANALYSIS SAMPLE ANALYSIS (6 m/s)
Parameter Minimum Maximum AverageBulk Avg
Surface area [m^2]
Pressure [Pa] 101295 101357 101346 0.503087Temperature [K] 293.216 293.219 293.219 0.503087Density [kg/m^3] 1.19499 1.19554 1.19548 0.503087
Velocity [m/s] 6 6 6 0.503087X-component of Velocity [m/s] 0 0 0 0.503087Y-component of Velocity [m/s] 0 0 0 0.503087Z-component of Velocity [m/s] 0 0 0 0.503087Mach Number [ ] 0 0 0 0.503087Heat Transfer Coefficient [W/m^2/K] 0 0 0 0.503637
Shear Stress [Pa] 1.6934E-09 0.4234960.041189
1 0.503637Fluid Temperature [K] 293.216 293.219 293.219 0.503087Condensate Mass Fraction [ ] 0 0 0 0.503087Moisture Content [ ] 0 0 0 0.503087Heat Flux [W/m^2] 0 0 0 0.503637
X-component of Heat Flux [W/m^2] 0 0 0 0.503637
Y-component of Heat Flux [W/m^2] 0 0 0 0.503637Z-component of Heat Flux [W/m^2] 0 0 0 0.503637
Parameter Value X-component Y-component Z-componentSurface area [m^2]
Heat Transfer Rate [W] 0 0 0 0 0.503637Normal Force [N] 7.32404 6.35504 0.0277127 3.64064 0.503637
Shear Force [N] 0.00678798 0.00373995 -0.000430454 -0.00564838 0.503637Force [N] 7.32448 6.35878 0.0272823 3.63499 0.503637Torque [N*m] 9.02615 -0.456129 8.98424 0.739427 0.503637Surface Area [m^2] 0.503637 -0.297528 -3.73079E-05 -0.167707 0.503637Torque of Normal Force [N*m] 9.02499 -0.45663 8.98306 0.73929 0.503637Torque of Shear Force [N*m] 0.00128868 0.000501344 0.00117918 0.000137376 0.503637Uniformity Index [ ] 1 0.503087CAD Fluid Area [m^2] 0.518222 0.518222
Velocity on blade ( m/s ) = 4.6
RPM = 33.15
P = 2Π N T/ 60
P = 31.314 Watt
P = 2 x 3.14 x 33.15 x 9.02499 / 60
This Power obtained is greater than Power for
conventional Savonius rotor
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CFD ANALYSIS
Air Flow Direction
Approx 4.6 m/s
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Sr. No. Inlet air Velocity (m/s)
Velocity on Blade (m/s) RPM
Power Output (Watt)
1 2 1.65 11.89 0.991
2 2.5 1.7 12.25 1.263
3 3 2.13 15.4 2.968
4 3.5 2.49 17.95 5.261
5 4 3.26 23.52 9.490
6 4.5 3.52 25.39 13.077
7 5 3.78 27.24 17.588
8 5.5 4.03 29.04 22.884
9 6 4.6 33.15 31.314
10 6.5 4.8 34.59 38.582
11 7 4.9 35.68 46.330
12 7.5 5.1 36.76 55.388
13 8 5.31 38.27 66.252
CFD ANALYSIS RESULTS FOR POWER GENERATION FROM CFD ANALYSIS
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CONTENT
Introduction
Literature Review
Design
CFD Analysis
Summary & Conclusion
Future Scope
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SUMMARY & CONCLUSION
Sr. No. Parameters Conventional Savonius wind Turbine
Modified Savonius wind Turbine
(Design suggested by this thesis)
1 Height of Blade (H) (mm) 1620 1620
2 Width of Blade (W) (mm) 350 350
3 Number of Blades 2 3
4 Diameter of Rotor (mm) 657.5 2000
5 Air Velocity considered (m/s) 6 6
6 Blade Material PVC FRP
7 Weight of Blade (Kg) 6.5 5.5
9 Coefficient of Power (Cp) 0.154 0.21
10 Tip Speed Ration (TSR) 0.65 0.69
11 Overlap Ratio ( )β 0.15 0
12 Rotor Aspect Ratio ( )α 1 0.7
13 Air Density (Kg/m3) 1.2 1.2
14 Theoretical Power (Watt) 21 88
15 Power Output CFD Analysis (Watt) 10 31
16 Actual Power Output (Watt) 7 - 8 25-28
The comparison between conventional Savonius wind turbine and the modified Savonius wind turbine
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The results from CFD analysis are found nearly same as the analytical calculations
From our theoretical analysis the power output for modified design is observed to be four times the conventional design
The power output from CFD analysis shows that the power output for modified design is three times the conventional design
The actual power output for modified is nearly three times of the conventional design
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SUMMARY & CONCLUSION
FINAL SETUP & TESTING
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The Test Model at testing plant of Breson Energy Ltd. Pune.
The Test results have validated the outputs achieved from our study.
CONTENT
Introduction
Literature Review
Design
CFD Analysis
Summary & Conclusion
Future Scope
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The Savonius wind turbine can be integrated with Solar cell systems to enhance power generation
The ducted turbine concept can be implemented for Savonius wind turbines to further increase its power efficiency
FUTURE SCOPE
[1] C.Chaudhari,S.Waghmare,A.kotwal,"Numerical analysis of venturi ducted horizontal axis wind turbine for efficent power generation"ISSN:2320-6349Volume(I),October2013
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Aditya S. Kasar, Ajinkya Shetye, Prof (Dr.) Vilas B. Shinde “Design Optimization of
Savonius Rotor for Wind turbine”, International Journal of Advances in Management
Technology & Engineering Sciences, ISSN: 2249-7455 , Vol. II, Issue 9 (I), June 2013.
Aditya S. Kasar, Chandan C. Chaudhari, Prof (Dr.) Vilas B. Shinde “Design and Analysis
of 5 KW Savonius Rotor Blade”, International Journal of Advances in Management
Technology & Engineering Sciences, ISSN: 2249-7455 ,Vol. II, Issue 10 (I), July 2013.
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AUTHOR PUBLICATIONS & REFRENCES
[1] JL Menet (2004), “A double step Savoniusrotor for the local generation of electricity: A design study,
Renewable Energy” (2004)
[2] Gupta, R., Biswas, A., Sharma, K. K. (2008), “Comparative study of a three bucket Savonius rotor with a
combined three bucket Savonius –three bladed Darrieus rotor. Renewable Energy”.
[3] Burcin Deda Altan, “Journal of Mechanical Science and Technology “ May 2012, Volume 26, Issue 5.
[4] UK Saha , S Thota, D Maity (2008), “Optimum design configuration of Savonius rotor through wind tunnel
experiments” ; Journal of Wind Engineering and Industrial Aerodynamics 96 (2008).
[5] C.Chaudhari, S.Waghmare, A.kotwal, "Numerical analysis of venturi ducted horizontal axis wind turbine for
efficient power generation“ ISSN:2320-6349 Volume(I),October2013
[6] Sargolazei J(2007), “Prediction of power ratio and torque in wind turbine Savonius rotors using artificial
neural networks”, Proceedings of the WSEAS International Conference on Renewable Energy Sources,
Arcachon, France, October Page (14-16)
[7] Wind Turbine Technology by A.R.JHA
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AUTHOR PUBLICATIONS & REFRENCES
[8] Aerodynamics of Wind Turbines By Martin O. L.Hansen
[9] Md. I. Hassan, T.Iqbal, N. Khan, M.Hinchey, V.Masek(2009), “CFD analysis of a twisted Savonius wind turbine”
Memorial University of Newfoundland, Canada.
[10] Kamoji. M. A, S. B. Kedare and S. V. Prabhu (2008), “Experimental Investigations on the Effect of Overlap
Ratio and Blade Edge Conditions on the Performance of conventional Savonius Rotor”, Wind engineering,
Volume 32, No. 2, pp 163–178
[11] Manual from Breson Wind Energy System.
[12] http://sauerenergy.com/
[13] http://www.turbinesinfo.com/innovative-wind-turbines
[15] http://www.search.com/reference/Savonius_wind_turbine
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AUTHOR PUBLICATIONS & REFRENCES
THANK YOU