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Transcript of 20120307 NiblickA Pres Micropower
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NNMREC
ExperimentalandAnalyticalStudyofHelicalCrossFlowTurbinesforaTidal
Micropower GenerationSystem
AdamNiblick
UniversityofWashington
NorthwestNationalMarineRenewableEnergyCenter
MSME Thesis DefenseMarch 7, 2012
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Outline TidalMicropower SystemOverview
TurbineSelection/DesignParameters
ExperimentalTesting
Modeling
ConclusionsandFutureWork
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MotivationforMicropower AdmiraltyInlet potential
siteoftidalturbineinstallationforcommercial
power NNMRECEnvironmental
sitecharacterizationmonitoring SeaSpiderbottomlander
tripod Instrumentationrequires
power Currentlybattery powered Grid,solarandwindnot
feasible
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MotivationforMicropowerBatteryCapacity(Whr): 165 Cost($/Whr): 1.15$
Unit
Power
Usage (W)
Deployment
Duration
(days)
Total
W-hr
#of batteries
Required Battery Cost
DopplerCurrentProfiler 0.9 90 1944 12 2,280.00$
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MotivationforMicropowerBatteryCapacity(Whr): 165 Cost($/Whr): 1.15$
Unit
Power
Usage (W)
Deployment
Duration
(days)
Total
W-hr
#of batteries
Required Battery Cost
DopplerCurrentProfiler 0.9 90 1944 12 2,280.00$DopplerCurrentProfiler 0.9 180 3888 24 4,560.00$
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MotivationforMicropowerBatteryCapacity(Whr): 165 Cost($/Whr): 1.15$
Unit
Power
Usage (W)
Deployment
Duration
(days)
Total
W-hr
#of batteries
Required Battery Cost
DopplerCurrentProfiler 0.9 90 1944 12 2,280.00$DopplerCurrentProfiler 0.9 180 3888 24 4,560.00$ImagingSonar(20%dutycycle) 20.0 180 86400 524 99,560.00$
u0:Inflowvelocity
:Fluiddensity
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MotivationforMicropowerBatteryCapacity(Whr): 165 Cost($/Whr): 1.15$
Unit
Power
Usage (W)
Deployment
Duration
(days)
Total
W-hr
#of batteries
Required Battery Cost
DopplerCurrentProfiler 0.9 90 1944 12 2,280.00$DopplerCurrentProfiler 0.9 180 3888 24 4,560.00$Imaging
Sonar
(20%
duty
cycle) 20.0 180 86400
524 99,560.00$
ImagingSonar(20%dutycycle) 20.0 180 86400 15 2,850.00$
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Micropower SystemConcept
Drawing courtesy of Stelzenmuller et al
Micropower System A tidal hydrokinetic power generation system to
power remote instrumentation on the order of 20 W continuous in 1.5
m/s peak tidal currents.
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ResearchGoalsProvideinitialconceptforamicropower tidalgenerationsystem
Providedetaileddesign,analysisandexperimentaltestingoneofthecomponents:thehydrokineticturbine
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Micropower SystemBlockDiagram
+ +
Loads
Monitoring Equipment
Controller/processor
Data storage
Gearbox
Generator
Tidal
Turbine
BatteryBank
ConverterRectifier
Turbine
Controller
Loads
0 2 4 6-2
0
2
time (days)
u0
(m/s)
Tidal Current Profile
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Outline Micropower SystemOverview
TurbineSelection/DesignParameters
ExperimentalTesting
Modeling
ConclusionsandFutureWork
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NNMREC
TurbinePerformanceMetrics Efficiency forpowerandtorqueproduction
Startingtorquemagnitudeandrange forselfstart
TipSpeedRatioandRotationRate forgeneratorintegration
Performancewithrespecttoinfloworientation fordeploymentflexibility
H:Height
D:Diameter
R:Radius
T:Torque
u0:Inflowvelocity
:Fluiddensity:Azimuthal angle
:Angularvelocity
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TurbineDesignConcepts
Axial
Turbine
Savonius
Rotor
Darrieus
Turbine
Hybrid
Turbine
Helical
Turbine
Sources: Polagye, 2011; engr.mun.ca/~tariq/jahangiralam.pdf; newenergycorp.ca;
Highefficiency
(~35%) Good selfstart
capability
Accepts flowfromanyhorizontaldirection
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NNMREC
BladeElementTheory Streamwise velocity(uS) Tipvelocity(R)
Inducedbyturbinesownrotation Relativevelocity(u
REL
) Resultantvectorof
uS and R Angleofattack()
AnglebetweenuREL andchordline
Lift DragForces(FL,FD) Generateturbinetorque
Bestliftdragratiowhen10<
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Axialvs.CrossFlowTurbines
Tidal Flow is Parallel to Axis
of Rotation
Tidal Flow is Perpendicular
to Axis of Rotation
Axial Cross-Flow
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BladeElementTheory Angleofattack()
Constantlychangingas
turbinerotates Oftenexceedsstallangle
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HelicalTurbineParameters BladeProfile
BladePitch
HelicalPitch
AspectRatio
SolidityRatio/Chordto
RadiusRatio NumberofBlades
BladeWrap
AttachmentDesign
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HelicalTurbineParameters BladeProfile
HelicalPitch
AspectRatio
SolidityRatio/ChordtoRadiusRatio
NumberofBlades AttachmentDesign
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-0.1
0
0.1
x
y
NACA0018
Source: answers.com
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HelicalTurbineParameters BladeProfile
HelicalPitch
AspectRatio SolidityRatio/Chordto
RadiusRatio
NumberofBlades AttachmentDesign
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HelicalTurbineParameters BladeProfile
HelicalPitch
AspectRatio SolidityRatio/Chordto
RadiusRatio
NumberofBlades AttachmentDesign
Sizelimitedbydeploymentconstraints
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HelicalTurbineParameters BladeProfile
HelicalPitch
AspectRatio SolidityRatio/Chordto
RadiusRatio
NumberofBlades(B) AttachmentDesign
30% Solidity
15% Solidity
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HelicalTurbineParameters BladeProfile
HelicalPitch
AspectRatio SolidityRatio/Chordto
RadiusRatio
NumberofBlades AttachmentDesign
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ParameterOptimizationHigherefficiency,
ImprovedCP,
Manufacturability
Helical PitchLowerstatictorque
variation
ImprovedCP,
Allows higherpitchAspectRatio EasierDeployment,Lessbladestress,
Lessvibration
Betterstartingtorque,
ManufacturabilitySolidityRatio Highertipspeedratio
Allowsincrease inpitch
andreducedaspect
ratio
NumberofBlades Fewerparts,Lessbladewakeinterference
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Outline Micropower SystemOverview
TurbineSelection/DesignParameters
ExperimentalTesting
Modeling
ConclusionsandFutureWork
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TurbinePrototypes
3Blades D=20cm
H=20cm 1.00AspectRatio 43.7 PitchAngle 30%Solidity
3BladedTurbineBaselineConfiguration
4BladedTurbine LowSolidityTurbine
3Blades D=20cm
H=20cm 1.00AspectRatio 43.7 PitchAngle 15%Solidity
4Blades D=17.2cm
H=23.4cm 1.36AspectRatio 60 PitchAngle 30%Solidity
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NNMREC
TestsPerformed
BaselineConfiguration
LoadPerformanceTest
StaticTorqueTest TiltedTurbineTest
DesignComparisonTests
HelicalPitch/No.ofBlades StrutAttachmentDesign
ShaftDesign
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FlumeTestChannel
3meterslength 72cmwide Maximum0.8m/sflow
rate Turbinelocatedincenter
offlumewidthat1.7mfromtestchannelinlet
AcousticDopplerVelocimeter (ADV) to
measureflumevelocity
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TestInstrumentation
Module
Reaction Torque Cell
Particle Brake Flex Coupling
Optical Encoder
Locking Plate
Bearing
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TurbineOperation
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LoadPerformanceResults Baseline
Configuration
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Liftand
Drag
for
different
Region of TurbineOperation at 0.4 m/s
Region of TurbineOperation at 0.8 m/s
but increasing decreases average
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StaticTorque Baseline
Configuration
Flume:0.7m/s
0 view,lookingdownstream
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NNMREC
TurbineDesignComparison
4-Bladed Turbine3-Bladed TurbineLoad Performance
Test Results
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StrutDesignComparison2 mm Spoke 4.8 mm Spoke Circular Plate
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ShaftDiameterComparisonNo Shaft 6.4 mm Shaft 12.7 mm Shaft
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NNMREC
TiltedTurbine
Test
Downstreamendofturbineframeinclined
0,2.5,5and10degreeinclinations
Performancetest
Baseline
spoke
design
and
circularplateconfigurations
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TiltedTurbineTest
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TestConclusions Fourbladedturbineisbestdesignforoptimum
aspect
ratio
and
performance Goodselfstart andperformancewithhighsolidity
MaximizehelicalpitchangletogetbettermaxCP
Noimpact
of
shaft
diameter
onperformance
Circularplate bestattachmentdesign eliminatesprofiledrag,bettertiltangleperformance
Static
torque
is
not
uniform HigherinflowvelocitygivesbetterCP
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Outline Micropower SystemOverview
TurbineSelection/DesignParameters
ExperimentalTesting
Modeling
ConclusionsandFutureWork
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NNMREC
VortexModel Freevortexflowmodel
Bladedividedintoseveralelements
BladeelementperformancefromCL,CD lookuptables
Bladeselementssimulatedasvortexgenerators
SumofvelocitycomponentsgivesuREL
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VortexModel Comparisontoothermodeltypes
LesscomputationaltimethanCFD(daysvs.minutes)
Comparedtomomentummodels,thevortexmodel: Canresolvehelicalgeometrywithoutyawcorrectionfactors
Betterresolvesthewake
ModelModifications
Helicalgeometry
Strutdragforcircularplateandendspokes
Flowcurvatureeffects
HigherCR thanpreviouslymodeled
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FlowCurvature Changein fromleadingedgetotrailingedge
Important forhighchordtoradiusratioturbines
Approximated as
Virtual camber
Source: Migliore, 1980
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Pitchingand
Dynamic
Stall Lift,dragaffectedbypitchrate
Virtualincidence Approximatedby
CL calculated
from
at
chord CD calculatedat atchord Biases positive
Dynamicstall Vortexformsattheleadingedgeofhydrofoilandtracksback
alongthechord Liftisincreasedduringtracking Liftdropsasvortexfullysheds
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-0.1
0
0.1
x
y
NACA0018
Source: Ekaterinaris & Platzer, 1997
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DynamicStallLift Drag
Source: NASA, 2009
Implementation of Secondary
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ImplementationofSecondary
EffectsExperimental Data at
0.8 m/s
Implementation of Secondary
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ImplementationofSecondary
EffectsExperimental Data at
0.8 m/s
Model Prediction withno Secondary Effects
Implementation of Secondary
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ImplementationofSecondary
Effects Experimental Data at0.8 m/s
Model Prediction withno Secondary Effects
Dynamic Stall added
Implementation of Secondary
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ImplementationofSecondary
Effects Experimental Data at0.8 m/s
Model Prediction withno Secondary Effects
Dynamic Stall added
Dynamic Stall & Pitch
Rate Effects added
Implementation of Secondary
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ImplementationofSecondary
Effects
Model Prediction withno Secondary Effects
Dynamic Stall added
Dynamic Stall & Pitch
Rate Effects added
Dynamic Stall, Pitch
Rate & Flow Curvature
Effects added
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NNMREC
ModelPrediction
ofInflow
Variation
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NNMREC
Extrapolation
to
1.5
m/s
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Analysis
of
High
Tip
Speed
Ratio
Flow
curvature
disabled
CP=0.43
Flow
curvature
active
CP=0.46
2 3 4 5 6 7 8 9 10-0.1
-0.05
0
0.05
0.1
0.15
0.2
(a)
Normalized Time (t*u0/R)
CQ
=2.6, 1.5 m/s
2 3 4 5 6 7 8 9 10
-16
-8
0
8
16
24
32
(d
egrees)
CQ
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Analysis
of
High
Tip
Speed
Ratio
Duetohighchordtoradiusratio: Flowcurvatureaddsinstabilitytomodeloutput Pitchrateeffectsanddynamicstalloveramplifyingperformance
Thiseffecthasbeendocumentedinpreviousliterature(Daietal.,2011),(Cardona,1984)
3/410
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Analysis
of
High
Tip
Speed
Ratio
Duetohighchordtoradiusratio: Flowcurvatureaddsinstabilitytomodeloutput Pitchrateeffectsanddynamicstalloveramplifyingperformance
Thiseffecthasbeendocumentedinpreviousliterature(Daietal.,2011),(Cardona,1984)
3/410
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P j C l i
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ProjectConclusions Demonstratedneedforandviabilityofatidalmicropower
system
Designedaturbineforamicropower system 24%efficientat0.8m/s(andincreasingwithflumespeed)
Goodselfstartandfloworientationcapabilities
Optimizedselecthelicalturbinedesignparameters
Modifiedavortexmodeltoaccepthelicalturbinedesign Demonstratedimportanceofsecondaryeffects
Demonstratedgeneraltrendsinperformance
Needforfurtherstudyofsecondaryeffectsforhighchordto
radiusratioturbines
F t W k
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FutureWork Testingofthefullscaleturbine
Designofsystemdrivetrainandcontrol
TurbineGenerator matching Selectionofbatterytype
Improvingturbineefficiency
Improvedturbinemodeling Examinationandrefinementofsecondaryeffects
Othermodeltypes(CFD,etc.)
A k l d t
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Acknowledgements Dr.BrianPolagye
Dr.AlbertoAliseda
Dr.BrianFabien Dr.RoyMartin
Dr.PhilipMalte
BillKuykendall
KevinSoderlund,EamonMcQuaide
Dr.JimThomson&APL
CapstoneDesignTeam:
NickStelzenmuller,BronwynHughes,Josh
Anderson,Celest Johnson,BrettTaylor,LeoSutanto
NNMRECOrganization
SandiaNationalLabs
Marie
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Questions?
B k Slid
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BackupSlides
System Performance
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NNMREC
SystemPerformance
System Performance
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NNMREC
SystemPerformance Turbinegeneratormatching
Desiredgeneratorcharacteristics Lowspeedoperation
6080rpmfordirectdrive
Highefficiency
Flatefficiencycurve
FitswithinSeaSpidersizeconstraints
Lowstartingtorque,lowcogging
Battery Information
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BatteryInformationCharacteristic SealedLeadAcid NiMH NiCd LithiumIon
EnergyDensity(Wh/L)[1] Low
5090
High
430
Low
15 100
High
570
CycleLife(cycles)[1] Low
200 500
Medium
300 1000
High
1500
High
1000+
MemoryEffect[4] LowNoeffect
MediumLess thanNiCd
High
Periodic discharge
required
LowNoeffect
ChargingTime[2] High
816hours
Medium
24hours
Low
about1hour
Medium
14hours
Cost[3]
($/kWh)Low
$8.50
Medium
$18.50
LowMedium
$11.00
High
$24
Toxicity[2] Veryhigh Low Veryhigh Low
TransportationLimitations[4] No No No Yes
Comments[1,4] Slowchargingtime;
lowenergydensity
Generatesheat
duringhighrate
chargeordischarge;
tolerantof
overcharge
oroverdischarge
Rugged;lowestcost
percycle;some
limitations onuse
duetotoxicity
Transportation
limitations;requires
complexcircuitto
operatesafely;
limitedavailability
forhighpower
applicationsDataSource:
[1]Reddy&Linden(2011) [2]Buchmann(2010d) [3]Buchmann(2011b) [4]Buchmann(2010e)
Helical Turbines
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HelicalTurbines Liftstyledevice
Advantages:
Easilyselfstarts Fairlyhighefficiency
(~35%)
Notorqueoscillation
Disadvantages:
Difficulttomanufacture
Lessefficientthanstraightbladeturbine
Blade Element Theory
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BladeElementTheory Lift DragForce
Normal Tangential
Force
Helical Turbine Parameters
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HelicalTurbineParameters BladeProfile
Helical Turbine Parameters
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HelicalTurbineParameters BladeProfile
BladePitch
HelicalPitch AspectRatio
SolidityRatio/Chordto
RadiusRatio NumberofBlades
BladeWrap
Strut/shaftDesign
Helical Turbine Parameters
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HelicalTurbineParameters BladeProfile
BladePitch
HelicalPitch AspectRatio
SolidityRatio/Chordto
RadiusRatio NumberofBlades
BladeWrap
Strut/shaftDesign
100% Wrap
50% Wrap
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TestMatrix
Startup
Shutdown
Wake
Measure
ment
0.8 0.7 0.6 0.5 0.4 0.78 0.7 00.7 0.78
TurbineDe si gn StrutDesign
Shaft
Diameter
(mm)
Single
blade
length
Full
Revolution
LoadPer
formance
Static
Torque
SingleBlade,from
4bladedturbineCircularPlates 6.4
X X X
4.8mm,4leg
spokes6.4
X X X
NoshaftX X X
6.4 X X X X X X X X X X X
12.7X X X
CircularPlates 6.4X X X X X X X X
3bladedturbine4.8mm,3leg
spokes6.4
X X X X X X
LowSolidity
Turbine
4.8mm,3leg
spokes
6.4
X X
X:TestCompleted
FlumeVelocity(m/s):
Performancetest TiltedTurbine
2.0mm,4leg
spokes4bladedturbine
0.7
Dynamic
TorqueTurbineGeometry StaticTorque
0.72
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TestCalculations
Parameter Symbol
FlumeSpeed(m/s) u0 0.4 0.8
StaticWaterHeight(cm) hsw 50 46
DynamicWaterHeight(cm) h0 49 42
WaterColumnCrossSectionalArea(m2) AF 0.371 0.318
TurbineCrossSectionalArea (m2) AC 0.040 0.040
BlockageRatio 0.108 0.126
FroudeNumber Fr 0.182 0.394
MaxBladeReynold'sNumber(4BladedTurbine) ReB 4.0E+04 9.5E+04
MinBladeReynold'sNumber(4BladedTurbine) ReB 3.6E+03 2.2E+04
MachineReynold'sNumber(4BladedTurbine) ReM 7.7E+04 1.5E+05
DataRange
Typical Test Results
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TypicalTestResultsLoadPerformanceTest StaticTorqueTest
Typical Test Results
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TypicalTestResultsLoadPerformanceTest StaticTorqueTest
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Streamwise View=0 =20 =40 =70
Static torque near maximum Static torque
drops
Single Blade Static Torque
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SingleBladeStaticTorque
Single Blade Torque Superposition
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SingleBladeTorqueSuperposition
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Streamwise View=0 =20 =40 =70
Static torque near maximum Static torque
drops
Unobstructed
(-T) bladePartial
obstruction of
(+T) blade at
location of
best drag
TurbineDesignComparison
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4-Bladed Turbine
3-Bladed Turbine Static Torque TestResults
TiltedTurbineTest
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Strut
Design
TiltAngle
(degrees)
Tilt
Velocity
Predicted
CPLoss
from
cos(Tilt)
ActualCP
Loss
0 0.720 0.0% 0.0%
2.5 0.719 0.2% 5.6%
5 0.717 0.7% 8.8%
10 0.709 2.8% 23.0%
0 0.720 0.0% 0.0%
2.5 0.719 0.2% 4.5%
5 0.717 0.8% 4.4%
10 0.709 3.3% 8.9%
2mm,4Leg
Spoke
2mm
Circular
Plate
Wake
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NNMREC
MeasurementTest Baseline
Configuration
Flume:0.78m/s
Wakemeasurementsalongturbinecenterline
Startup 1012x 10
-3
m
(a)
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p
Shutdown
TestProfile 0 20 40 60 80 100 12-20
2
4
6
8
TurbineTorque,Nm
0 20 40 60 80 100 120
100
200
300
400
TurbineAngle,
Degrees (b)
0 20 40 60 80 100 120
0.2
0.4
0.6
0.8
Time, s
UVelocity,m/s
(c)
StartingAngle LoadTorque(Nm) CutInSpeed(m/s) CutOutSpeed
0 0.006 0.47 0.21
10 0.006 0.47 0.21
20 0.006 0.47 0.21
30 0.006 0.58 0.22
40 0.006 0.60 0.20
50 0.006 0.57 0.19
60 0.006 0.60 0.23
70 0.006 0.55 0.18
80 0.006 0.47 0.23
0.53 0.21
0 0.021 0.71 0.38
Averagecut
in/cut
out
speed
at
0.006
Nmloadtorque:
VortexModel
-
7/29/2019 20120307 NiblickA Pres Micropower
80/86
NNMREC
Bladeisdividedintosegments,revolutionintotimesteps
8elementsperblade
15revolutionstoestablishwake
Vortexinfluencestheflowofsurroundingblades
ModelSolution
-
7/29/2019 20120307 NiblickA Pres Micropower
81/86
NNMREC
SumofvelocitycomponentsgivesuREL
Totalchangeincirculationovertimeiszero(Kelvinstheorem):
VortexinducedvelocityatapointisfoundbyBiotSavart Law:
CirculationstrengthisfoundfromKutta
Joukowski theorem: Predictorcorrectorto
solvesystemofequations
BoeingVertol DynamicStall
-
7/29/2019 20120307 NiblickA Pres Micropower
82/86
NNMREC
Model
-
7/29/2019 20120307 NiblickA Pres Micropower
83/86
NNMREC
FlowCurvature Changein fromleadingedgetotrailingedge Important forhighchordtoradiusratioturbines
Approximated as
Virtual camber
FullScaleTurbinePrediction
-
7/29/2019 20120307 NiblickA Pres Micropower
84/86
NNMREC
All SecondaryEffects Active
FullScaleTurbinePrediction
-
7/29/2019 20120307 NiblickA Pres Micropower
85/86
NNMREC
Dynamic Stallonly
ModelPredictionofStrutDrag
-
7/29/2019 20120307 NiblickA Pres Micropower
86/86
NNMREC
u0=0.8m/s