Revisiting the Vertical-Axis Wind-Turbine Design using Advanced

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Transcript of Revisiting the Vertical-Axis Wind-Turbine Design using Advanced

Page 1: Revisiting the Vertical-Axis Wind-Turbine Design using Advanced

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Page 2: Revisiting the Vertical-Axis Wind-Turbine Design using Advanced

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NACA0015 Lift & Drag Coefficients

Sample Experimental Data

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icie

nt

Lift

Drag

ÅmnoehjY�_�� �*×�]�a|]��e�gØx����»Cr _�Y�ml¹�_�d�kQw\i�stml��k�@�Æ�YQw\o°acZ�_�ºby�mn_�d�k�f|[«Åghjini�]�inrjzgwb��±|_�_0rtÃ

0.0

0.2

0.4

0.6

0.8

1.0

1.2

0.0

-0.2

-0.4

-0.6

-0.8

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.40.0

JC Vassberg01 JAN 2005

NACA0015 Drag Polar

Sample Experimental Data

Drag Coefficient

Lif

t C

oeff

icie

nt

ÅmloqhjY�_ � ��×�]�a|]��q�jØÜ�I�*»�r _�Y�mn¹._0d�k�w\itÆ�YQw\ovÓ�Zeiµw\Yc[cÅjhgili�]�ilrgzgwv��±c_0_�rtÃèié3ê+ê�ë4ìbíïî�ð�ñmò"óiô1õié3ö1÷ùøeúaé3û7ìWê"ò3õaðýü6þÁü6üeÿ é"ó�ìWí�������������� �bð���� � 5 ü6þÁü6ü ü����fð��mìbõiò�ð���è ����ò�����

Page 13: Revisiting the Vertical-Axis Wind-Turbine Design using Advanced

0.00

0.05

0.10

0.15

0.20

0.00

-0.05

-0.10

0.0 22.5 45.0 67.5 90.0 112.5 135.0 157.5 180.00.0

JC Vassberg01 JAN 2005

NACA0015 Thrust Coefficients

Sample Experimental Data

Angle-of-Attack (deg)

Thr

ust

Coe

ffic

ient

Nb = 1

ÅmloqhjY`_I� �*×�]�a|]��q�jØÜ�²®¯zjY�hgf�k�acZ�_�ºby�mn_�d�k�Æ�_0Y`mn�e_xXb��Y�Ze¹ ��»CrL_0Y`mn¹�_�d�k�weitÆ�w\k�wgÃ

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.00

-0.05

0.0 22.5 45.0 67.5 90.0 112.5 135.0 157.5 180.00.0

JC Vassberg01 JAN 2005

NACA0015 Thrust Coefficients

For 5- & 6-Blade Turbines

Angle-of-Attack (deg)

Tot

al T

hrus

t C

oeff

icie

nt

Nb = 5

Nb = 6

ÅmloqhjY`_2� ����k�w\Y`k�[^��r+®¯zjY�hgf�k�acZ�_�ºby�mn_�d�k�f¯hgf`mndjo°� @ ��u|inwqXC_0f0Ãèié3ê+ê�ë4ìbíïî�ð�ñmò"óiô1õié3ö1÷ùøeúaé3û7ìWê"ò3õaðýü6þÁü6üeÿ é"ó�ìWí�������������� �bð���� � 5 ü6þÁü6ü ü����fð��mìbõiò�ð���è ���ò�����

Page 14: Revisiting the Vertical-Axis Wind-Turbine Design using Advanced

NACA CT6 AIRFOIL GRID 256 X 64ÅmloqhjY�_J} �«a«[¼¹�_0f`z�±�mÂk�zA��mµf`y�Zehgf�acinhgf�k`_�Y�mndjovw\· ZehCk�w�×�]�a|] �\�q]��jØx�8]�mlY`��ZemniTÃ

−1 −0.8 −0.6 −0.4 −0.2 0 0.2 0.4 0.6 0.8 1

−0.1

−0.05

0

0.05

0.1

alpha

Cl

4 time intervals8 time intervals12 time intervalsAGARD−702:Davis

ÅmnoehjY�_�Ø0� ��×�]�a|]4�e�q]��gØ0�.Æ�W�dgwe¹�mny2s�mÂ��k�s�Z�ZqrtÃèié3ê+ê�ë4ìbíïî�ð�ñmò"óiô1õié3ö1÷ùøeúaé3û7ìWê"ò3õaðýü6þÁü6üeÿ é"ó�ìWí�������������� �bð���� � 5 ü6þÁü6ü ü����fð��mìbõiò�ð���è � �ò�����

Page 15: Revisiting the Vertical-Axis Wind-Turbine Design using Advanced

0.00

0.02

0.04

0.06

0.08

0.10

0.00

-0.02

-0.04

-0.06

-0.08

-0.10

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.10.0-0.1

JC Vassberg30 DEC 2004

NACA0015 (Solid)

WARP0015-RC8 (Dash)

WARP0015-RC8 Camber Line

NACA0015 Airfoil Geometry

X

Y

ÅmnoehjY�_�ØeØ �*acZq¹�rgw\Y�mnf`Zed�Z\��×�]�a|]��q�jØÜ�I@ �´]�Ù�Óc�e�gØx�Ü[^Ù�a|�²]�mlY`��Zemnië��_xy�k`mnZedLf�Ã0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

0.0

0.00.0

0.20.4

0.60.8

1.01.2

1.41.6

1.82.0

Troposkien (Solid)Catenary (Dash)

JC V

assberg30 D

EC

2004

r / R

h / R

Comparison of Troposkien & Catenary Curves

ÅmnoehjY�_�Ø � �*acZq¹�rgw\Y�mnf`Zed�Z\��®�Y�Zer Zqf`³�ml_0d @6a|wNk`_0dgw\Y�W�achjY��e_xf�Ã

èié3ê+ê�ë4ìbíïî�ð�ñmò"óiô1õié3ö1÷ùøeúaé3û7ìWê"ò3õaðýü6þÁü6üeÿ é"ó�ìWí�������������� �bð���� � 5 ü6þÁü6ü ü����fð��mìbõiò�ð���è ���ò�����

Page 16: Revisiting the Vertical-Axis Wind-Turbine Design using Advanced

0.0

0.5

1.0

1.5

2.0

0.0

-0.5

-1.0

-1.5

-2.0

0 5 10 15 200-5-10-15-20

JC Vassberg30 DEC 2004

FLO103 / (256 x 64) / Baldwin-Lomax

NACA0015 Airfoil Lift Curve

M = 0.3 , Ren = 2M

Angle-of-Attack

Sect

ion

Lif

t C

oeff

icie

nt

ÅmnoehjY�_�Ø0� ��Å�s �8Øx�e�vacZe¹�rjhCk�_0X ! � [�>=achjY��e_eÃ

0.0

0.5

1.0

1.5

2.0

0.0

-0.5

-1.0

-1.5

-2.0

0.000 0.005 0.010 0.015 0.020 0.025 0.0300.000

JC Vassberg30 DEC 2004

FLO103 / (256 x 64) / Baldwin-Lomax

NACA0015 Airfoil Drag Polar

M = 0.3 , Ren = 2M

Section Drag Coefficient

Sect

ion

Lif

t C

oeff

icie

nt

ÅmnoehjY�_�Ø�� ��Å�s/�8Ø0�e�vacZe¹�rjhjk`_0X�Æ�Y�weo.Ó�ZqinweY0Ã

èié3ê+ê�ë4ìbíïî�ð�ñmò"óiô1õié3ö1÷ùøeúaé3û7ìWê"ò3õaðýü6þÁü6üeÿ é"ó�ìWí�������������� �bð���� � 5 ü6þÁü6ü ü����fð��mìbõiò�ð���è � 3�ò�����

Page 17: Revisiting the Vertical-Axis Wind-Turbine Design using Advanced

0

5

10

15

0

-5

-10

-15

0 45 90 135 180 225 270 315 3600

JC Vassberg30 DEC 2004

Geometric Angle-of-Attack

Chi = 5.0

Theta (deg)

Alp

ha (

deg)

ÅëmnoehgY`_�Øx� �*p;_�Ze¹�_�k`Y�mnyJ]�dgoein_�[ÄZ\��[^]|k�k�wqyQ³ �*w\Y�mnw\k`mnZed���ZeY ) 6 � � �jÃ

15

20

25

30

35

40

0 45 90 135 180 225 270 315 3600

JC Vassberg30 DEC 2004

On-Set Dynamic-Pressure Cycle

Chi = 5.0

Theta (deg)

On-

Set

Dyn

amic

-Pre

ssur

e R

atio

ÅëmnoehgY`_�Ø%� �'��dC[^�C_�k�Æ�W�dLw\¹�mnyJÓ«Y`_xf`f`hjY�_;Ù�w\k`mnZ �*w\Y�mnw\k`mnZed���ZeY ) 6 � � �gÃèié3ê+ê�ë4ìbíïî�ð�ñmò"óiô1õié3ö1÷ùøeúaé3û7ìWê"ò3õaðýü6þÁü6üeÿ é"ó�ìWí�������������� �bð���� � 5 ü6þÁü6ü ü����fð��mìbõiò�ð���è � ��ò�����

Page 18: Revisiting the Vertical-Axis Wind-Turbine Design using Advanced

0

10

20

30

40

0

-10

-20

-30

-40

0 45 90 135 180 225 270 315 3600

JC Vassberg30 DEC 2004

Section Lift-Coefficient Cycle

Chi = 5.0

Theta (deg)

Sect

ion

Lif

t C

oeff

icie

ntR

efer

ence

d T

o F

rees

trea

m V

eloc

ity

ÅëmnoehgY`_�Ø � �/�*w\Y�mnw\k`mnZed"Z\�s�mÂ��k���ZeY ) 6 � � �gÃ

0

10

20

30

40

0

-10

-20

-30

-40

0 5 10 150-5-10-15

JC Vassberg30 DEC 2004

0 < Theta < 90

90 < Theta < 180

180 < Theta < 270

270 < Theta < 360

Lift-Alpha Loop

Chi = 5.0

Alpha (deg)

Sect

ion

Lif

t C

oeff

icie

nt

ÅmnoehjY�_�Ø0� ��s�mÂ��k;stZ�Zer���ZeY ) 6 � � �jÃèié3ê+ê�ë4ìbíïî�ð�ñmò"óiô1õié3ö1÷ùøeúaé3û7ìWê"ò3õaðýü6þÁü6üeÿ é"ó�ìWí�������������� �bð���� � 5 ü6þÁü6ü ü����fð��mìbõiò�ð���è � �ò�����

Page 19: Revisiting the Vertical-Axis Wind-Turbine Design using Advanced

0

10

20

30

40

0

-10

-20

-30

-40

0 5 10 150-5-10-15

JC Vassberg30 DEC 2004

0 < Theta < 90

90 < Theta < 180

180 < Theta < 270

270 < Theta < 360

Comparison of Lift-Alpha Loops

Chi = 5.0

Alpha (deg)

Sect

ion

Lif

t C

oeff

icie

nt

Geometric Method

FLO Code: NACA0015

FLO Code: WARP0015

ÅmloqhjY`_�Øx} �«acZe¹�rgweY`mµf�Zqd°Ze����W�¹�¹�_�k`Y�W�[ÄÓ«inwedj_2��_0y�k`mnZedgweitstml��k�stZ�ZerLf|��ZeY ) 6 � � �gÃ

0

10

20

30

40

0

-10

-20

-30

-40

0.0 0.5 1.0 1.5 2.0 2.5 3.00.0-0.5

JC Vassberg30 DEC 2004

0 < Theta < 90

90 < Theta < 180

180 < Theta < 270

270 < Theta < 360

Comparison of Drag-Polar Loops

Chi = 5.0

Section Drag Coefficient

Sect

ion

Lif

t C

oeff

icie

nt

Geometric Method

FLO Code: NACA0015

FLO Code: WARP0015

ÅmloqhjY�_#�e� �«acZe¹�rgweY`mµf`Zed°Ze���CW�¹�¹�_�k�Y`W�[^Ó*iµw\dj_2��_xy�k`mnZedLw\itÆ�Y�weo\[^Ó�Zeiµw\Ycs�Z�Zergf|��ZqY ) 6 � � �gÃèié3ê+ê�ë4ìbíïî�ð�ñmò"óiô1õié3ö1÷ùøeúaé3û7ìWê"ò3õaðýü6þÁü6üeÿ é"ó�ìWí�������������� �bð���� � 5 ü6þÁü6ü ü����fð��mìbõiò�ð���è ���ò�����

Page 20: Revisiting the Vertical-Axis Wind-Turbine Design using Advanced

0.0

0.5

1.0

1.5

2.0

0.0

-0.5

0 45 90 135 180 225 270 315 3600

NACA0015 CPs avg = 0.4845WARP0015 CPs avg = 0.4820

JC Vassberg30 DEC 2004

Comparison of Section Power-Coefficient Cycles

Chi = 5.0

Theta (deg)

Sect

ion

Pow

er C

oeff

icie

nt

Geometric Method

FLO Code: NACA0015

FLO Code: WARP0015

ÅmnoehjY�_:�CØ �«acZq¹.rLw\Y�mnf`Zed�Z\���CW�¹�¹�_�k�Y`W�[^Ó*iµw\dj_���_xy�k�mlZqdgw\itÓ�ZN±|_�Y�acWCy�in_0f|��ZeY ) 6 � � �jÃ

0

-20

-40

-60

-80

-100

0

20

40

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.00.0

JC Vassberg01 JAN 2005

Chi = 5.0 , R/C = 8.0 , AR = 5.0 , M = 0.1 , Re = 1M

WARP0015-RC8 H-Type Single-Blade Turbine

Symmetry-Plane Pressure Distributions

X/C

Pre

ssur

e C

oeff

icie

nt

Theta = 000

Theta = 090

Theta = 180

Theta = 270

ÅëmnoehgY`_:� � �*��W�¹.¹�_�k`Y�Wq[^Ó*iµw\dg_;Ó«Y`_xf`f`hjY�_;Æ�mnf�k`Y�mn·jhCk`mnZedLf|��ZeY ) 6 � � �.w\k �*w\Y�mlZqhgf�acilZCyQ³°Ó�Z�f�mlk`mnZedLf�Ãèié3ê+ê�ë4ìbíïî�ð�ñmò"óiô1õié3ö1÷ùøeúaé3û7ìWê"ò3õaðýü6þÁü6üeÿ é"ó�ìWí�������������� �bð���� � 5 ü6þÁü6ü ü����fð��mìbõiò�ð���è � ��ò�����

Page 21: Revisiting the Vertical-Axis Wind-Turbine Design using Advanced

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.0

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.00.0

JC Vassberg03 JAN 2005

UFLO107 , Chi = 5.0 , M = 0.1 , Re = 1M

NACA0015 & WARP0015-RC8 H-Type Turbines

Computed Spanwise Variation of Power

Eta

Sect

ion

Pow

er C

oeff

icie

nt

NACA: CP-TOT = 0.3117

WARP: CP-TOT = 0.3238

ÅmloqhjY�_#�e� �*acZe¹�rjhCk�_0X+��rgwedjinZqweXgf¯Z\��k�zj_�×�]�a|]��e�gØx� @ �´]�Ù�Ó«�q�jØÜ�Ü[^Ù�a|�²V�[^®«W�r _�®�hjY�·jmndj_0f�w\k ) 6 � � �gÃ

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.00

0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0.180.00

JC Vassberg03 JAN 2005

UFLO107 , Chi = 5.0 , M = 0.1 , Re = 1M

NACA0015 H-Type Turbine

Solidity

Pow

er C

oeff

icie

nt

ÅëmnoehgY`_:�N� � � ��_0y�k�Ze����ZqilmµXCmlk�W°Zqd"Ó�ZN±|_�Y�acZ�_�ºby�mn_�d�k���ZeY¯k�zj_�×�]�a|]��e�gØx�8V�[^®«W�r _J®ëhjY�·jmndj_�wNk ) 6 � � �jÃèié3ê+ê�ë4ìbíïî�ð�ñmò"óiô1õié3ö1÷ùøeúaé3û7ìWê"ò3õaðýü6þÁü6üeÿ é"ó�ìWí�������������� �bð���� � 5 ü6þÁü6ü ü����fð��mìbõiò�ð���è ��ò�����

Page 22: Revisiting the Vertical-Axis Wind-Turbine Design using Advanced

0.00

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0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50

0.00

0 2 4 6 8 10 12 14 160

JC Vassberg03 JAN 2005

2-Blade Turbine

1-Blade Turbine

3-Blade Turbine

Darrieus 17M Turbine

Comparison of Power Distributions

Chi

Pow

er C

oeff

icie

nt

UFLO107 Results

Sandia 2-Blade Data

Sandia 3-Blade Data

ÅmloqhjY�_ �q� �«acZe¹�rgweY`mµf�Zqd°Ze��Æ;w\Y�Y`mn_�hLf�Ø?��\-Ó�ZN±c_0Y|Æ�mµf�k�Y`mn·jhCk�mlZqdgf�Ã

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.00

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.00.0

JC Vassberg03 JAN 2005

CP-TOT = 0.3163 , Chi = 5.0 , Omega = 50.6 RPM

Darrieus 17M Turbine

Computed Spanwise Variation of Power

Eta

Sect

ion

Pow

er C

oeff

icie

nt

ÅmnoehjY�_:�j� �*acZq¹�rjhCk`_xX+��rgw\dgilZ�weXbZe�ëk�zj_�Æ;w\Y�Y`mn_�hgf;Ø?��\-®�hjY�·jmndj_�wNk ) 6 � � �jÃèié3ê+ê�ë4ìbíïî�ð�ñmò"óiô1õié3ö1÷ùøeúaé3û7ìWê"ò3õaðýü6þÁü6üeÿ é"ó�ìWí�������������� �bð���� � 5 ü6þÁü6ü ü����fð��mìbõiò�ð���è ����ò�����

Page 23: Revisiting the Vertical-Axis Wind-Turbine Design using Advanced

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50

0.00

0 1 2 3 4 5 6 7 8 9 100

JC Vassberg03 JAN 2005

SAND78-1737 Test Data , Omega = 42.0 RPM

Reverse Engineered Sectional Power Coefficient Distribution

System Total Power Coefficient

Darrieus 17M Turbine

Variation of Total Power with Blade Speed

Chi

Pow

er C

oeff

icie

nt

Sandia Test Data

Section CpRevEng

Integrated CpRevEng

ÅëmnoehgY`_:�� ��Ù�_��q_�YQf�_xX �«djoemndj_�_0Y`_xX���_xy�k�mlZqdgw\itÓ�ZN±|_�Y�acZ�_�ºby�mn_�d�k�f|��Y�Ze¹ ��WCf�k�_�¹ ®ëZ\kQw\itÆ�mnf�k`Y�mn·jhCk`mnZed�Ã

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

0.50

0.00

0 1 2 3 4 5 60

JC Vassberg03 JAN 2005

CP-TOT = 0.3163 , Chi = 5.0 , Omega = 50.6 RPM

Darrieus 17M Turbine

Variation of Power with Local Blade Speed

Chi

Sect

ion

Pow

er C

oeff

icie

nt

UFLO107 Results

Reverse Engineered Cp

ÅmloqhjY`_:�e� �«acZe¹�rgweY`mµf�Zqd°Ze����_xy�k�mlZqdgw\itÓ�ZN±|_�Y�acZ�_�ºby�mn_�d�k�Æ�mµf�k`Y�ml·jhjk`mnZedgf¯��ZqY�Æ�weY`Y�mn_�hgfJØ?��\-wNk ) 6 � � �gÃèié3ê+ê�ë4ìbíïî�ð�ñmò"óiô1õié3ö1÷ùøeúaé3û7ìWê"ò3õaðýü6þÁü6üeÿ é"ó�ìWí�������������� �bð���� � 5 ü6þÁü6ü ü����fð��mìbõiò�ð���è ��ò�����