Navier-Stokes Modeling for HAWT by CFX 5.7

Navier-Stokes Modeling for HAWT by CFX 5.7

Chapter 2

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Rotor Geometry

1. Diameter : 54.5 m1. Diameter : 54.5 m

2. Rated Power : 1MW (Design wind speed – 10 m/s)2. Rated Power : 1MW (Design wind speed – 10 m/s)

6. Airfoil Sections : NACA 63415, NACA 63418, DU-Series, 6. Airfoil Sections : NACA 63415, NACA 63418, DU-Series, FFA Series (From Tip to Hub)FFA Series (From Tip to Hub)

3. TSR : 7.5 (Design point)3. TSR : 7.5 (Design point)

4. Rotating Speed : 26.28 rpm4. Rotating Speed : 26.28 rpm

5. Power Control Type : Stall regulated5. Power Control Type : Stall regulated

FIL-1000


Details of Specification

Local Posistion Twist(deg) Position(mm) Chord (mm) Airfoil series

0.20 17.9 5450 2629.25 FFA-W-301

0.25 14.4 6812 2524.09 FFA-W-301

0.30 11.7 8175 2418.94 FFA-W-301

0.35 9.73 9537 2313.79 FFA-W-301

0.40 8.14 10900 2208.63 DU91-W2-250

0.45 6.87 12262 2103.48 DU91-W2-250

0.50 5.83 13625 1998.32 DU93-W2-210

0.55 4.97 14987.5 1893.17 DU93-W2-210

0.60 4.24 16350.0 1788.01 DU93-W2-210

0.65 3.62 17712.5 1682.86 DU93-W2-210

0.70 3.08 19075.0 1577.71 NACA63(2)-418

0.75 2.60 20437.5 1472.55 NACA63(2)-418

0.80 2.17 21800.0 1367.4 NACA63(2)-418

0.85 1.77 23162.5 1262.24 NACA63(2)-418

0.90 1.35 24525.0 1157.09 NACA63(2)-415

0.95 0.83 25887.5 1051.93 NACA63(2)-415

1.00 0.83 27250.0 946.78 NACA63(2)-415

ROOT

TIP


Geometry Modeling




Computational Mesh

• Mesh Generation : ICEM-CFD 5.0

• Mesh Type : Unstructured Hexa

• 480,000 nodes


Computational Mesh

• Chord length : 175 nodes

• Radial direction : 40 nodes

• O-GRID


Computational Mesh

• Chord length : 175 nodes

• Hybrid-Mesh : Casing (Tetra-Prism)

• 220,000 nodes

Turbulence Modeling

# K-W SST Model with High Resolution# K-W SST Model with High Resolution

- Accounts for the transport of the turbulence shear stress and givesAccounts for the transport of the turbulence shear stress and gives very highly accurate predictions of the onset and the amount of very highly accurate predictions of the onset and the amount of flow separation under adverse pressure gradients flow separation under adverse pressure gradients

- Improve the accuracy for the predictions of the flow separation from Improve the accuracy for the predictions of the flow separation from a smooth surface : Important phenomenon in many industrial fields,a smooth surface : Important phenomenon in many industrial fields, particularly for airplane industriesparticularly for airplane industries

- The most prominent two equation model The most prominent two equation model

Ref.: Menter, F.R.., “Two equation eddy-viscosty turbulence models for engineering applications”Ref.: Menter, F.R.., “Two equation eddy-viscosty turbulence models for engineering applications” AIAA Journal, 32(8), 1994 AIAA Journal, 32(8), 1994


Calculation Conditions

TSR Wind Speed Rotating Speed

2 37.48 m/s 26.28 rpm

3 24.98 m/s 26.28 rpm

4 18.74 m/s 26.28 rpm

5 14.99 m/s 26.28 rpm

6 12.49 m/s 26.28 rpm

7.5 9.99 m/s 26.28 rpm

9 8.33 m/s 26.28 rpm

10 7.49 m/s 26.28 rpm

11 6.81 m/s 26.28 rpm

12 6.24 m/s 26.28 rpm

13 5.76 m/s 26.28 rpm


Boundary Conditions• Inflow (Normal velocity)

• Outflow (Static Pressure)

• Periodic surfaces(GGI)

• Frame change model : Frozen rotor Interface with rotor and casing

• Rotating Frame + Stationary Frame


Results

TSR : 3 TSR : 7.5 TSR : 10

Surface Pressure Distribution on the Suction Side

TSR : 3 TSR : 7.5 TSR : 10

Surface Streamline on the Suction Side

Results

TSR : 3 TSR : 7.5 TSR : 10

Sliced Streamline – 5m from Root

Results

TSR : 3 TSR : 7.5 TSR : 10


Results

TSR : 3 TSR : 7.5 TSR : 10


Results

TSR : 3 TSR : 7.5 TSR : 10


Results

Results


확보실험 데이터 (Riso)

: Wind rotor airfoil catalog

날개 끝 손실계수모델의 적용

Prandtl’s tip loss 이론

기본형상 설계 완료 및 형상 최적화

항력을 고려한 설계- 형상최적화

Blade Element Momentum 이론

성능계수 평가 및 비교



3차원 CFD 해석 : CFX- 5.7b

Fluid Structure Interaction (FSI)

로터 구조해석(유동해석과 연계)


허브 설계(구조해석)

너셀 및 동력전달 장치의 설계

타워 설계 및 풍력시스템 설계완료

풍력터빈 용량결정

로터 직경결정, 주속비 결정

기본형상 설계

BEM 이론

2- D 익형 공력특성 확보

X- foil, Visual foil: MIT Aero&Astro

2- D 익형 공력특성 확보실험 데이터 (Riso)










3차원 CFD 해석 : CFX- 5.7


로터 구조해석( ANSYS 연계)
























기본형상 설계

BEM 이론







































기본형상 설계

BEM 이론







































기본형상 설계

BEM 이론




















수행완료

진행 예정

Future Works


Documents

Navier-Stokes Modeling for HAWT by CFX 5.7