Jointed AT BladeJointed AT Blade

Shu Ching Quek Shu Ching Quek (Presenter)(Presenter)Baehmann PeggyBaehmann PeggyYerramalli ChandraYerramalli ChandraMiebach ThomasMiebach ThomasFaidi WaseemFaidi Waseem

General Electric General Electric Global Research CenterGlobal Research Center

2 / 9/2/2009

GE Proprietary

Logistics of Transporting BladesLogistics of Transporting Blades

Key Benefits•Standardized joint design•Reduce transportation costs •Reduce escort and route

limitations•Competitive feature

Typical blade length shipping cost

Lower costLower cost

$

miles

Jointed BladeJointed Blade

Increases transportability

3 / 9/2/2009

GE Proprietary

Ongoing and Tested Concepts To DateOngoing and Tested Concepts To Date

LM, TU Delft, WMC

Enercon E-126 (7+ MW)Rotor diameter 126 m

WeightBlade Freq

Dynamic ResponseRoot Moment

Torsional StiffnessBlade twist

Tailor Blade designLimited Spar Cap Fab

Field Assembly /Maintenance

Ease of assemblySpace requirement

ReliabilityCloser to root causeshigh torque / momentIncreases fatigue risks

Joint Type

Bolted / Bonded

Bolted / BondedBolted / Bonded

Bolted / Bonded

Reference: European Space Agency PSS-03-203 Issue 1, Structural Materials Handbook, vol.1

4 / 9/2/2009

GE Proprietary

Analysis and Downselection CTQsAnalysis and Downselection CTQs

Global-Local analysis performed to design and analyze blade

joint region

FE Structural Blade Model

Extreme Loads@ Joint Section

FE 3D Solid Sub-Component Model of Joint

DisplacementsRotations

Applied to

Output

Applied to

Output

Joint Component Stresses

Loads obtained from GE Structural Group Blade Design Team

Compare to

Respective Material Limits

Jointed AT Blade

5 / 9/2/2009

GE Proprietary

Testing and Validation of Subscale Joint Testing and Validation of Subscale Joint DesignDesign

Nonjointed

Jointed

Static Spanwise

Static Edgewise

Cyclic Spanwise

Cyclic Edgewise

Blade 1 & 2 Positive Edgewise (Pulling up with LE facing up)

-0.008

-0.006

-0.004

-0.002

0

0.002

0.004

0.006

0.008

23x

24x

25x

40x

41x

42x

36x

37x

38x

46x

47x

Strain Gage

Str

ain

Analysis B1 FX 88, B1 Loc

Test B1 F2 Edge Static +45,700 lb E9 After F

Analysis B2 FX 94, B2 Loc

Test B2 F2 Edge Static +49,800 lb E13 Before F

TE TE Core LE Core LE

SBJ1 SBJ2 SBJ1 SBJ2

SBJ2SBJ1 SBJ1 SBJ2

FF FF

FF

SBJ1 & SBJ2 = 25 mm Each Side of Skin Butt JointFF = Far Field

Material Limit

Material Limit

Design Allowable

Design Allowable

6 / 9/2/2009

GE Proprietary

In-Field Assembly ConceptsIn-Field Assembly Concepts

7 / 9/2/2009

GE Proprietary

Adhesive SelectionAdhesive Selection

Adhesive requirements

Mechanical propertiesTensile strength & modulusShear strength & modulusPeel strength

Fatigue performance

Process robustnessSurface preparation and conditionsEnvironmental conditionsApplication via injection process

Detectable for in-line quality control

Datasheet & design variables

Application performance

Ready for use infield assembly

Development focus on process robustness and NDE development

8 / 9/2/2009

GE Proprietary

Quality Control Quality Control

Conventional post-cure inspection versus real-time monitoring technology

Ultrasound scanning system for post cure inspection and c-scan images

Bottom Side

LE

TE

LE

TE

(%FSH)

0 200 400 600 800 1000 1200 1400 1600 1800 20000

200

400

Top Side

0 200 400 600 800 1000 1200 1400 1600 1800 20000

200

400

Ferrite adhesive real-time monitoring and a snap shot of the adhesive flow

Joint line

Injection Tube

adhe

sive

flow

path

Video clip view window

9 / 9/2/2009

GE Proprietary

Full Scale Validation on 2.5MW PlatformFull Scale Validation on 2.5MW Platform

Strain gages for flap and twist

Accelerometers Camera On-tower test On-ground testing for

extreme and 20-year fatigue life