Post on 25-Feb-2016
description
Design and Calculus of the Foundation Structure of an
Offshore Monopile Wind Turbine
Author: Carlos Garcés GarcíaDirected by: Julio García Espinosa
ContentsIntroductionWind TurbineEmplacementLoadsGrout ConnectionTransition PieceMonopileFoundationLoads AnalysisConclusions
Monopile
A Monopile?Its Parts
The PileThe GroutThe Transition
PieceFunction
The Offshore Wind Turbine
Rating 5 MWRotor Orientation, Configuration Upwind, 3 BladesControl Variable Speed, Collective
PitchDrivetrain High Speed, Multiple-Stage
GearboxRotor 126 mHub Diameter 3 mHub Height 90 mCut-In, Rated, Cut-Out Wind Speed 3 m/s, 11.4 m/s, 25 m/sCut-In, Rated Rotor Speed 6.9 rpm, 12.1 rpmRated Tip Speed 80 m/sOverhang, Shaft Tilt, Precone 5 m, 5º, 2.5ºRotor Mass 110,000 kgCoordinate Location of Overall Center of Mass
(-0.2 m, 0.0 m, 64.0 m)
NREL 5MW Wind Turbine
EmplacementLocalisation: 39º 15’N, 74º
15’WAverage Wind Speed: 6,38 m/sDistance to Coast: 28 kmDepth: 20mSoil: Unconsolidated SandWeather Extremes:
Extratropical Storms
Loads
Waves
Wind Height 13,80 m 90,00 m
Design Situation U ( m/s)Gust (m/s) U (m/s)
Gust (m/s)
Start Up 3Normal Operative 6,38 24,69 8,02 27,44Shut Down 25Extreme Sea State 23,97 29,58 26,63 32,97Return- 50 years from ESS 33,56 41,41 37,48 46,42
Design Situation h (m) T (s) λ (m) ω (rad/s) c (m/s) a ()Average Wave 1,00 5,55 48,09 1,13 8,67 1,28ESS 8,40 10,50 172,13 0,60 16,39 3,01
Wind Force CalculusOn the Rotor
Operating Conditions
Stoped Rotor Conditions
On the Tower
NREL FAST-AeroDyn Soft
Waves Force CalculusMorison’s Equation
Inertia Coefficient Drag Coefficient
Water Pressure
Monopile Virtual Model
SeaFEM AnalysisWave Amplitud: 8,4 mWave Period: 5,55 s
Dimensions
MaterialsCharacteristics Ducorit ® D4Compressive strength 210 MPaTension strength 10 MPaModulus of elasticity 70 GPaDensity 2.740 Poisson’s ratio 0.19Static coefficient of friction (Grout-Steel)
0.6
Characteristics SteelYoung’s Modulus 210 GPaPoisson’s Modulus 0,3Torsion Modulus 81 GPaMaximal Stress 235,2 MPaSpecific Weight 76.900 N/m³
Boundary ConditionsFoundation: Linear Soil Spring
Vertical Constrain at Pile’s Bottom Tip
Wind loads
Wave loads from SeaFEM
Self Weight
(kN) X (m)
K (kN/m) y (mm) p (kN/m)
19.750,70 18
1.944.000 10,15 4.022,81
Maximal Stresses
ConclusionsObjectives AccomplishedCalculus ComplexityFeasible ConstructionNecessary Informatic Tools
ConsiderationsEnvironmental DegradationEconomical FeasabilityProtection Against Corrosion