On the Aerodynamic Properties of Slotted-Flap Flow-Control Devices for Wind Turbine Applications

110 Pages·2016·11.59 MB·English

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Dissertations, Master's Theses and Master's Reports
2016
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Muraleekrishnan Menon Menon Muraleedharan Nair
Michigan Technological University, [email protected]
Copyright 2016 Muraleekrishnan Menon Menon Muraleedharan Nair
RReeccoommmmeennddeedd CCiittaattiioonn
Menon Muraleedharan Nair, Muraleekrishnan Menon, "On the Aerodynamic Properties of Slotted-Flap
Flow-Control Devices for Wind Turbine Applications", Open Access Master's Thesis, Michigan
Technological University, 2016.
https://doi.org/10.37099/mtu.dc.etdr/134
Follow this and additional works at: https://digitalcommons.mtu.edu/etdr
Part of the Energy Systems Commons
ONTHEAERODYNAMICPROPERTIESOFSLOTTED-FLAPFLOW-CONTROL
DEVICESFORWINDTURBINEAPPLICATIONS
By
MuraleekrishnanM.Menon
ATHESIS
Submittedinpartialfulfillment oftherequirements forthedegreeof
MASTEROFSCIENCE
InMechanicalEngineering
MICHIGANTECHNOLOGICALUNIVERSITY
2016
©2016MuraleekrishnanM.Menon

This thesis has been approved in partial fulfillment of the requirements for the Degree of
MASTEROFSCIENCEinMechanicalEngineering.
DepartmentofMechanicalEngineering-EngineeringMechanics
ThesisAdvisor: Dr.FernandoL.Ponta
Committee Member: Dr.LuciaGauchia
Committee Member: Dr.LeonardJ.Bohmann
Department Chair: Dr.WilliamW.Predebon

Dedication
To my brother, Krishnakumar M.
whohasalwaysbeenagreatinspiration topursuescience

Contents
ListofFigures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix
ListofTables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvii
Nomenclature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xix
ListofAbbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxi
Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxiii
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Loadmitigation approaches . . . . . . . . . . . . . . . . . . . . . . . . 5
1.2 Futureofloadcontrol . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.3 Activeflow-controldevicesforaerodynamiccontrol . . . . . . . . . . . 9
2 Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.1 Meshdesign . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
2.2 Turbulencemodeling . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
2.3 Adaptivemeshgeneration . . . . . . . . . . . . . . . . . . . . . . . . . 25
2.4 Computational approach . . . . . . . . . . . . . . . . . . . . . . . . . 30
vii
3 Validation Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
3.1 NACA23012Validationcase . . . . . . . . . . . . . . . . . . . . . . . 39
4 NumericalExperiments . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
4.1 StudyofNACA643-618 . . . . . . . . . . . . . . . . . . . . . . . . . 47
4.2 StudyofDU93-W-210 . . . . . . . . . . . . . . . . . . . . . . . . . . 60
5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
A CopyrightAgreements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
viii
List of Figures
1.1 SchematicsoftwooperationalwindturbinesmanufacturedbyVestasillus-
trates the scale of wind turbines and puts the rated power in perspective of
rotordiameter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.2 Illustration of progressive trend towards cost reduction through economies
of scale factor, producing more power with the use of larger turbine ro-
tors. Figure reproduced from UpWind project report by Fichaux et al. [1],
©EuropeanWindEnergyAssociation. (SeeAppendixAforproofthatthis
materialisinthepublicdomainforreuse). . . . . . . . . . . . . . . . . 4
1.3 Examplesofflow-controldevices: (a)PlainFlap,(b)ExternalFlap . . . 10
1.4 Schematicviewofthetrailing-edgeflapandthemodularattachment . . 12
2.1 Initial mesh designed for Computation Fluid Dynamic analysis of
NACA 643-618 with Clark Y profile trailing-edge flap. Top panel: global
view of the grid space before initiating adaptive mesh refinement, bottom
panel: closer view of the initial mesh. Notice denser mesh near the airfoil
surfacewithelementsgrowing insizetowardsthefar-fieldboundary. . . 18
ix