PREDICTION THE EFFECT OF TIP SPEED RATIO ON WIND …Hari Pal Dhariwal 1*, Dharampal Yadav and Barun...
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125 PREDICTION THE EFFECT OF TIP SPEED RATIO ON WIND TURBINE GENERATOR OUTPUT PARAMETER Hari Pal Dhariwal 1 *, Dharampal Yadav 1 and Barun Kumar Roy 2 *Corresponding Author: Hari Pal Dhariwal, [email protected] In wind turbine design blade and speed of rotor is one of the most important parts. Power obtained from the wind can only be extracted when a better design with increased rotor speed. Generator selection and its power can be calculated easily which is important factor for wind turbine design. Keywords: Tip Speed Ratio (TSR), Revolution Per Minute (RPM), Horizontal Axis Wind Turbine (HAWT) INTRODUCTION Wind is caused by uneven heating and cooling of the earth’s surface and by the earth’s rotation . The amount of energy produced by a wind machine depends upon the wind speed and the size of the blades in the machine. In general, when the wind speed doubles, the power produced increases eight times. Larger blades capture more wind. As the diameter of the circle formed by the blades doubles, the power increases four times. A best tip-speed ratio depends on the number of blades in the rotor. The fewer blades, the faster the wind turbine spins to extract maximum power from the wind. Early ISSN 2278 – 0149 www.ijmerr.com Vol. 1, No. 3, October 2012 © 2012 IJMERR. All Rights Reserved Int. J. Mech. Eng. & Rob. Res. 2012 1 Singhania University, Rajasthan, India. 2 OITM, Hisar. experiments showed that a two-blade rotor has an optimum tip-speed ratio of about 8, a three- blade design about 6, and four blades, about 4. However, more recent highly efficient aerofoil designs have increased the numbers by 25 to 30%, which allows increasing rpm and therefore generating more power. Serhat (2005) investigated aerodynamic design of HAWT blades. Wind turbine blades are the pivot of the other parts of a wind turbine in electricity production since they extract the energy from the wind and carry this energy to generators which produce electricity. David and Daniel (2003) worked on the blades of a modern wind turbine are key Research Paper
Transcript of PREDICTION THE EFFECT OF TIP SPEED RATIO ON WIND …Hari Pal Dhariwal 1*, Dharampal Yadav and Barun...
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Int. J. Mech. Eng. & Rob. Res. 2012 Hari Pal Dhariwal et al., 2012
PREDICTION THE EFFECT OF TIP SPEED RATIOON WIND TURBINE GENERATOR OUTPUT
PARAMETER
Hari Pal Dhariwal1*, Dharampal Yadav1 and Barun Kumar Roy2
*Corresponding Author: Hari Pal Dhariwal,[email protected]
In wind turbine design blade and speed of rotor is one of the most important parts. Powerobtained from the wind can only be extracted when a better design with increased rotor speed.Generator selection and its power can be calculated easily which is important factor for windturbine design.
Keywords: Tip Speed Ratio (TSR), Revolution Per Minute (RPM), Horizontal Axis Wind Turbine(HAWT)
INTRODUCTIONWind is caused by uneven heating and coolingof the earth’s surface and by the earth’srotation . The amount of energy produced by awind machine depends upon the wind speedand the size of the blades in the machine. Ingeneral, when the wind speed doubles, thepower produced increases eight times. Largerblades capture more wind. As the diameter ofthe circle formed by the blades doubles, thepower increases four times.
A best tip-speed ratio depends on thenumber of blades in the rotor. The fewer blades,the faster the wind turbine spins to extractmaximum power from the wind. Early
ISSN 2278 – 0149 www.ijmerr.comVol. 1, No. 3, October 2012
© 2012 IJMERR. All Rights Reserved
Int. J. Mech. Eng. & Rob. Res. 2012
1 Singhania University, Rajasthan, India.2 OITM, Hisar.
experiments showed that a two-blade rotor hasan optimum tip-speed ratio of about 8, a three-blade design about 6, and four blades,about 4. However, more recent highly efficientaerofoil designs have increased the numbersby 25 to 30%, which allows increasing rpm andtherefore generating more power.
Serhat (2005) investigated aerodynamicdesign of HAWT blades. Wind turbine bladesare the pivot of the other parts of a wind turbinein electricity production since they extract theenergy from the wind and carry this energy togenerators which produce electricity.
David and Daniel (2003) worked on theblades of a modern wind turbine are key
Research Paper
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Int. J. Mech. Eng. & Rob. Res. 2012 Hari Pal Dhariwal et al., 2012
components, central to all aspects of the
system from energy capture to system
dynamics to tower clearance. They are also
complex structural items, typically comprising
many layers of fiber reinforced material with
necessary shear webs, root fixtures, and
tapering cross sections.
Implementation of design improvements
within the wind turbine industry was hampered
by the lack of practical prediction tools having
the appropriate level of complexity.”
(Bermúdez et al., 2002). Wind turbine design
graduated from the airfoil design industry with
much of the same theory being applied.
Based on the observations in past, work
was done in large size wind turbine blades.
As large size turbines will produce more
power.
Methodology and Detail of theProgram Designed for CalculatingVarious Wind Turbine Parameters
A Program is designed by me in VB.NETlanguage for the fast calculation and can findout desired result in short time . “Figure 1”shows the image of the Program which I namedas “Blade Calculator”.
The Important features of this program are:
• Code works on click of a button “CalculateOutput”.
• On click of button 2 functions are calledcaloutput, drawtable and output panel ismade visible.
• In this code 3 functions are used.
• Caloutput(): In this function all the out putvalues are calculated and assigned todesired lables to display the out put on form.
Figure 1: Image of Blade Calculator
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Int. J. Mech. Eng. & Rob. Res. 2012 Hari Pal Dhariwal et al., 2012
• Drawtable(): In this function table containgradius, chord and beta has been drwanusing Table Layout Panel control of Visualstudio 2005.
• Getdatafromexcel(): In this function we findthe value of sin() from the excel filesintbl.xls (attached) on the basis of Angleod Attack () to calculate Coefficient of Liftin caloutput() function.
• Code, excel and image of form design isattached.
RESULTS AND DISCUSSION
Effect of TSR
Case 1: Data is calculated by taking variousvalues shown below:
No. of Blades = 2
Blade Radius = 0.8 (in meter)
Blade Efficiency = 0.35
TSR = 6
Wind Speed = 10 m/s
Angle of Attack = 4 Degree
Then
Click on the designed software
Calculate Output
Output Parameters will display
Power = 430.8 Watt
RPM of Generator = 716 RPM
Generator Torque = 6.01 Nm
Coefficient of Lift = 0.438
Data are shown in Figure 2 given below.
Figure 2: Blade Calculator for Case 1
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Int. J. Mech. Eng. & Rob. Res. 2012 Hari Pal Dhariwal et al., 2012
Case 2: Here TSR changes to 7, then Dataare shown in Figure 3 below.
Case 3: Here TSR changes to 8, then Dataare shown in Figure 4 below.
Figure 3: Blade Calculator for Case 2
Figure 4: Blade Calculator for Case 3
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Int. J. Mech. Eng. & Rob. Res. 2012 Hari Pal Dhariwal et al., 2012
Inputs Case 1 Case 2 Case 3 Case 4
No. of Blades (N) 2 2 2 2
Radius of Blade (r) 0.8 0.8 0.8 0.8
Efficiency () 0.35 0.35 0.35 0.35
TSR 6 7 8 9
Wind Speed (U) 10 11 12 13
Angle of Attack () 4 4 4 4
Outputs Case 1 Case 2 Case 3 Case 4
Power in Watt 430 573 744 946
RPM of Gent. 716 919 1146 1397
Gent. Torque 6.01 6.2 6.4 6.7
Coef. of Lift 0.438 0.438 0.438 0.438
Table 1: Effect of TSR on RPM
Figure 5: Blade Calculator for Case 4
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Int. J. Mech. Eng. & Rob. Res. 2012 Hari Pal Dhariwal et al., 2012
Figure 6: Tip Speed Ratio v/s RPM of Generator
Case 4: Here TSR changes to 9, then Dataare shown in Figure 5 below.
As seen from the Table 1, as the TSR isIncreased RPM of the Generator is alsoincreased shown by the graph in Figure 6.
CONCLUSIONBased on the observations RPM of thegenerator shaft is directly proportional to theTSR. Higher the TSR there will be an increasein the power output. This can be achieved bya better design of the wind turbine blade.
REFERENCES1. Bermúdez L, Velázquez A and Matesanz
A (2002), “Viscous-Inviscid Method for theSimulation of Turbulent Unsteady WindTurbine Airfoil Flow”, Journal of WindEngineering and IndustrialAerodynamics, Vol. 90, pp. 643-661.
2. David J Malcolm and Daniel L Laird(2003), “Modeling of Blades asEquivalent Beams for AeroelasticAnalysis”, AIAA Reno January, #0870.
3. Dhariwal Hari Pal (2010), “Wind TurbineDesign a Feasibility Study and Scope ofImprovement”, Soch-Masthnath Journalof Science and Technology India, Vol. 5,pp. 6-10.
4. Puneet Manwell J F, McGowan J andRogers T (2002), “Wind EnergyExplained: Theory, Design andApplication”, University of Massachusetts,Amherst, MA.
5. Seraht Duran (2005), “Computer-AidedDesign of Horizontal -Axis Wind TurbineBlades”, Middle East Technical University.
