Upload
matthew-cameron
View
20
Download
0
Embed Size (px)
Citation preview
Flow Field Measurements for a Cross Flow Tidal Turbine
Advisors:
M.L. Peterson, Professor of Mechanical Engineering
H. Xue, Professor of Marine Science
R.W. Kimball, Professor at Maine Maritime Academy
!"#$%&'()*##+,-+# -#
By Matthew Cameron
!"#$%&'()*##+,-+# +#
1. Tidal energy resource assessment ~ A step to understanding of the impacts of
turbines on flow and the potential size of this renewable energy resource
2. Power array density ~ A single high efficiency turbine might not yield
highest power array density
!." R#$#% P#&'% C()%)*$'%+,$+*, -.-
Figure !."#. Power coe/cients of wind rotors of di0erent designs ["]
Figure !."". Torque coe/cients of wind rotors of di0erent designs ["]
Eric Hue, “Wind Power”
Method:
Analyze a single wake from a cross flow turbine in a steady and uniform flow
Motivations!
!"#$%&'()*##+,-+# .#
Test Turbine!
• Outer Support
• Drive Shaft
• Inner Beam
• Horizontal Load Cell
• Turbine Support Arm
• Shroud
• Vertical Load Cell
Dynamometer & Drive Train
Blade Profile NACA 63018
~76. mm
Cross Flow Turbine
~0.3 meter
!"#$%&%'(!!)%*!"*++&!,-'%#!
Turbine Coefficients
Test Matrix
!"#$%&'()*##+,-+# /#
Turbine Force Coefficients!
!
Ci =Energy outEnergy in
B!
A!
The Acoustic Doppler Velocity Meter (ADV)!
!"#$!%&'()*%$+,-.$-/.$0-123,$#&3'1,$
./0!12'+32-$!4*+3-'%#2!
45 0*6/-3$)&$7&*(,$8-)*&$$
9$:-),8$/,,.,.$)&$;,$(,,.,.$*($-%&'()*%$2-8)*%3,($)&$1-*/)-*/$07<$=$4>$
?5 0-123,$<-),$@A$+B$
C5 #,3&%*)D$<-/6,$$$$E5EE4$)&$F$1(G4$9$H(,.$)I&$E5C1(G4$-/.$45E$1(G4$
A5 !%%'8-%*,($-8,$-$J'/%)*&/$&J$K,3&%*)D$8-/6,$-/.$(*6/-3$)&$/&*(,$8-)*&$
>5 L/),8/-3$.-)-$2&((,((*/6$9CG>$*/.*K*.'-3$2*/6($!$4$.-)-$2&*/)$
~1.1m
8m
0.55m
Water Surface
Z
X
0.156m
h3 h2
h1
h4
2.4m
0.761m
1.2m
Y
Sample Volume
Center Line
Experimental Setup!
!"#$%&'()*##+,-+# 0#
./0!5!6+%78'+&!'3%*#&
49+39%+6:!
$$$$$9$!"#$*($M&'/),.$)&$)N,$O3&&8$$$$
$$$$$9$P'8;*/,$&K,82-(($)N,$!"#$
$$$$$9$PN,$!"#$(-123,$K&3'1,$*($3&%-),.$&/$)N,$%,/),8$&J$)N,$$ )'8;*/,$-/.$)&I$)-/Q$*/$)N,$R$.*8,%)*&/$
$$$$$9$P'8;*/,$)8-K,3($4>$1,),8($-/.$!"#$*($3&%-),.$$ -228&S*1-),3D$*/$)N,$%,/),8$$
)+;'!0-3%-<$+;:!
$$$$$9$!"#T($(-123,$K&3'1,$N,*6N)$
$$$$$9$!"#T($#,3&%*)D$8-/6,$$$$$$9$U-88*-6,$.*8,%)*&/$
$$$$$9$V3-.,$2&(*)*&/$&8$P0<$$
Different Blade Positions Directly over ADV
Only for low solidity turbine (2 blade test) !
-# +# .#
Center Line !Of ADV#
C.L# C.L#
1#2%3'#45+,5+,--#
3. Repeatability of velocity measurements!
!"#$%&'()*##+,-+# 6#
Test Accuracy & Repeatability!
1. Combination of different velocity range! 2. Repeatability Of blade position at x = 0!
±3.5°!
One dot (") is one blade form one test!
1. Reynolds’ Time Averaging!! ~ Method of separating turbulent and steady flow!! ~ The results are need to determine 2 and 3 !
Wake Characteristics Objectives !
2. Turbulent Kinetic Energy (TKE)!! ~ Determines the amount of fluctuation !! ! ! energy per volume!!
UMeasured = U Mean + " U Fluctuation
!
U Mean = [u v w ]" U Fluctuation = [ " u " v " w ]
3. Reynolds’ Shear!! ! ~ Also know as turbulent shear!! ! ~ Depicts the amount of momentum transfer !! ! ! across a plane by turbulent motion!
!
TKE ="2( # u 2 + # v 2 + # w 2)
!
" turb =# u # v # v # w # w # u
$
%
& & &
'
(
) ) )
4. Energy Spectrum (Wavelet Transform)!! ! ~ Determines the magnitude of wide range of !! ! ! frequencies over a continues time period !
4#2%3'#45+,5+,--#!
WL = URaw(t)" #( f ,t)Time$
Frequency$
!
"( f ,t) =
!
" turb >> "Lam
Wake Analysis!
!"#$%&'()*##+,-+#-,#
Raw ADV Velocity Data!
Rotation Matrix!
4<=+>'%9+:!
$$$$9$P&$.,),81*/,$)N,$<,D/&3.($U&12&/,/)($WXY$Z[$
$$$$9$:*)N$X$-/.$Z$)N,$I-Q,$%N-8-%),8*()*%($%-/$;,$28,.*%),.$
?@@+>';:!
~ low pass filter effect on !
~ The cut off frequency for the filter was shown to be 10Hz
:*/.&I$(*B,$'(,.$\$?>
Free Stream
Laminar Flow
! = Vc ú " 0
!"#$%&'()*##+,-+# --#
Introduce Turbine & Surface Elevation Change
Power side
Return side
Effect on Surface Elevation
Influence: strong
1. Blockage effect
(ATurbine/Atank = 0.09)
2. Inflow Speed
3. Turbine height
4. Solidity
5. TSR
weak
!"#$%&'()*##+,-+# -+#
!"#$%&'()*##+,-+# -.#
Surface Elevation Change
Low Solidity Turbine (2 Blades) High Solidity Turbine (4 Blades)
!"#$%&'()*##+,-+# -/#
Surface Elevation Change for Low Solidity Turbine
~Fast Fourier transform of surface elevation equal to blade frequency
!"#$%&'()*##+,-+# -7#
Flow Field Visualization
Vector Field
U
u
w
!"#$%&'()*##+,-+# -0#
Notes: ~ Four blade high solidity turbine (0.32) ~ TSR 1.4 (on design) ~ Random blade position - Blade position is a minor effect on flow field
~ One Vector is the mean of four data points
!"#$%&'()*##+,-+# -1#
!"#$%&'()*##+,-+# -6#
Flow Field of Rotating Turbine Notes: ~ Two blades low solidity turbine (.16) ~ Three different blade position
~ One Vector is the mean of three data points
!"#$%&'()*##+,-+# -4#
Flow Field of Rotating Turbine
Flow Recovery
Laminar Flow
! = Vc U` " 0
X/D
!"#$%&'()*##+,-+# +,#
Flow Recovery using Reynolds !
1 0 1 2 3 4 5 6
1
0
1
u Mean for Position 1
Non Dimensional Distance (x/D)
Non
Dim
ensi
onal
Dis
tanc
e (x
/D)
& Ve
loci
ty (u
/Vc)
1 0 1 2 3 4 5 6
1
0
1
u’for Position 1
Non Dimensional Distance (x/D)
Non
Dim
ensi
onal
Dis
tanc
e (x
/D)
& Ve
loci
ty (u
/Vc)
1 0 1 2 3 4 5 6
1
0
1
u Mean for Position 3
Non Dimensional Distance (x/D)
1 0 1 2 3 4 5 6
1
0
1
u’for Position 3
Non Dimensional Distance (x/D)
1 0 1 2 3 4 5 6
1
0
1
u Mean for Position 2
Non Dimensional Distance (x/D)
1 0 1 2 3 4 5 6
1
0
1
u’for Position 2
Non Dimensional Distance (x/D)
!"#$%&'()*##+,-+# +-#
Low Solidity Turbine with Three Different Blade Positions
1 0 1 2 3 4 5 6
1
0
1
u Mean for Position 1
Non Dimensional Distance (x/D)
Non
Dim
ensi
onal
Dis
tanc
e (x
/D)
& V
eloc
ity (u
/Vc)
1 0 1 2 3 4 5 6
1
0
1
u’for Position 1
Non Dimensional Distance (x/D)
Non
Dim
ensi
onal
Dis
tanc
e (x
/D)
& V
eloc
ity (u
/Vc)
1 0 1 2 3 4 5 6
1
0
1
u Mean for Position 3
Non Dimensional Distance (x/D)
1 0 1 2 3 4 5 6
1
0
1
u’for Position 3
Non Dimensional Distance (x/D)
1 0 1 2 3 4 5 6
1
0
1
u Mean for Position 2
Non Dimensional Distance (x/D)
1 0 1 2 3 4 5 6
1
0
1
u’for Position 2
Non Dimensional Distance (x/D)
High Solidity Turbine
Region of Entrained Flow
Characteristics
!
u v w
"
#
$ $ $
%
&
' ' ' (
000
"
#
$ $ $
%
&
' ' '
u'v 'w'
"
#
$ $ $
%
&
' ' ' )
000
"
#
$ $ $
%
&
' ' '
L.E. Myers, (2010) !"#$%&'()*##+,-+# ++#
1 0 1 2 3 4 5 6
1
0
1
u Mean
Non Dimensional Distance (x/D)
Non
Dim
ensi
onal
Dis
tanc
e(z/
D) &
Vel
ocity
(U/V
c)
1 0 1 2 3 4 5 6
1
0
1
u Mean
Non Dimensional Distance (x/D)
Non
Dim
ensi
onal
Dis
tanc
e(z/
D) &
Vel
ocity
(U/V
c)
Off Design (TSR 0.9) Off Design (TSR 1.9)
1 0 1 2 3 4 5 61.75
1.25
0.75
0.25
0.25
0.75
1.25u Mean
Non Dimensional Distance (x/D)
Non
Dim
ensi
onal
Dis
tanc
e(z/
D)
& Ve
loci
ty(U
/Vc)
On Design (TSR 1.4)
u Mean for High Solidity & Different TSR
!"#$%&'()*##+,-+# +.#
1 0 1 2 3 4 5 6
1
0
1
u Mean for Position 1
Non
Dim
ensi
onal
Dis
tanc
e (z
/D)
& Ve
loci
ty (u
/Vc)
1 0 1 2 3 4 5 6
1
0
1
u Mean for Position 3
1 0 1 2 3 4 5 6
1
0
1
u Mean for Position 2
Non Dimensional Distance (x/D)
u Mean for Low Solidity & Different Blade Position
!"#$%&'()*##+,-+# +/#
Flow Bypass for High Solidity Turbine (0.32)
TSR Bypass Fraction
Power Side Return Side Total
0.9 0.033 0.013 0.05
1.4 (On design) 0.033 0.100 0.13
1.9 0.223 0.152 0.38
Results:#
!"#$%&'()*##+,-+# +7#
!
˙ V = wdA"
˙ V FB =˙ V Bypass
˙ V Re f
=wdx"
2# r# Vc
Flow Bypass for High Solidity Turbine (0.32)
Results:#
Free Spin 2.25 Prediction 0.65 to 0.75
!"#$%&'()*##+,-+# +0#
!
˙ V = wdA"
˙ V FB =˙ V Bypass
˙ V Re f
=wdx"
2# r# Vc
TSR Bypass Fraction
Total
Flow Bypass for Low Solidity Turbine (0.16)
Results:#
!"#$%&'()*##+,-+#+1#
TSR Blade Position
Bypass Fraction
Power Side
Return Side Total
2.25
1 ~0.032 ~0.052 ~0.08
2 ~0.043 ~0.091 ~0.13
3 ~0.045 ~0.068 ~0.11
Propagation of Turbulent Energy
!"#$%&'()*##+,-+# +6#
Turbulent Kinetic Energy for High Solidity Turbine (Vc=1.0ms-1)
!"#$%&'()*##+,-+# +4#1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
1.5
1
0.5
0
0.5
1
1.5
Turbulent Kinetic Energy
Non Dimensional Distance (x/D)
Non
Dime
nsio
nal
Dist
ance
(z/D
)&
Ener
gy p
er M
ass(
m2/
s2)
1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
1.5
1
0.5
0
0.5
1
1.5
Turbulent Kinetic Energy
Non Dimensional Distance (x/D)
Non
Dimensional Distance(z/D)
& Energy per Mass(m2/ s2)
1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
1.5
1
0.5
0
0.5
1
1.5
Turbulent Kinetic Energy
Non Dimensional Distance (x/D)
Non
Dime
nsio
nal
Dist
ance
(z/D
)&
Ener
gy p
er M
ass(
m2/
s2)
Reynolds Stress (u`w`) for High Solidity Turbine at (Vc=1.0ms-1)
!"#$%&'()*##+,-+# .,#
1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
1.5
1
0.5
0
0.5
1
1.5
Reynolds Shear
Non Dimensional Distance (x/D)
Non
Dime
nsio
nal
Dist
ance
(z/D
) &
She
ar(T
au/R
ho/V
c2)
1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
1.5
1
0.5
0
0.5
1
1.5
Reynolds Shear
Non Dimensional Distance (x/D)
Non
Dimensional Distance(z/D)
& Shear(Tau/Rho/Vc2)
1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
1.5
1
0.5
0
0.5
1
1.5
Reynolds Shear
Non Dimensional Distance (x/D)
Non
Dimensional Distance(z/D)
& Shear(Tau/Rho/Vc2)
Turbulent Kinetic Energy for Low Solidity Turbine at Vc=0.8ms-1
!"#$%&'()*##+,-+# .-#
Reynolds Stress (u`w`) for Low Solidity Turbine at Vc=0.8ms-1
!"#$%&'()*##+,-+# .+#
!"#$%&'()*##+,-+# ..#
Energy Spectrum
!"#$%&'()*##+,-+# ./#
Energy Spectrum
Energy Spectrum For High Solidity Turbine (Vc=1.0ms-1)
!"#$%&'()*##+,-+# .7#
!"#$%&'()*##+,-+# .0#
Energy Spectrum for Low Solidity Turbine (Vc=0.8ms-1)
The Flow Field
!"#$%&'()*##+,-+# .1#
Relation Turbulent Energy between Flow Bypass & Flow Recovery
How does turbulence diffusion compared to flow recovery & entrained flow?
X/D TKE " 0
!"#$%&'()*##+,-+# .6#
Reynolds Decomposition for High Solidity Turbine
!"#$%&'()*##+,-+# .4#
A#'+!
! BC!D#$$-*;+!#@!'8+!E+-2!+2'3-%2+&!F$#6!-'!B!'#!G!!
! ! &%-E+'+3;!>!;'+-E!@3#E!!H!0>!'#!IJ+3#!
! GC!)8+!F$K>'K-'%#2!9+$#>%'(!+L8%<%'!-!;K&&+2!<K%$&!K*!-2&!!!
! ! -<3K*'!+2&!#9+3!'8+!;-E+!;*->+!-;!'8+!E+-2!F$#6!>#$$-*;+! ! !
Reynolds Decomposition For Low Solidity Turbine
!"#$%&'()*##+,-+# /,#
!"#$%&'()*##+,-+# /-#
Lessons Learned
)8+!M-9+$+'!8-;!8%78+3!*#'+2'%-$!-;!-2!-2-$(;%;!'##$!
!!!!!!I!)K3<K$+2'!N%2+'%>!?2+37(!
! ! !
!! !
! BC!.!M-9+$+'!@#3!+->8!KO!9O!-2&!6!6#K$&!(%+$&!+L->'!PK-2'%'%+;!#@!'8+!,+(2#$&;!"'3+;;!
2. Achieving the highest Nyquist frequency possible with hardware
3. Resolve a wide spectrum of vortices
!
WL = U(t)" e2# "i( t$ to ) f dfdt%%
!
TKE " WL( f ,t)df#
!
WLu = u(t)" #(t, f )dfdt$$WLv = v(t)" #(t, f )dfdt$$WLw = w(t)" #(t, f )dfdt$$
!
RS "WLu#WLwWLv#WLwWLv#WLu
!"#$%&'()*##+,-+# /+#
Lessons Learned
)8+!M-9+$+'!8-;!8%78+3!*#'+2'%-$!-;!-2!-2-$(;%;!!'##$!
!!!!!!I!Q3+$%E%2-3(!6-9+$+'!%2'+73-'%#2!3+;K$';!(%+$&%27!)K3<K$+2'!N%2+'%>!?2+37(!
! ! !
!! !
!"#$%&'()*##+,-+# /.#
University Of Maine
MTPI
Huijie Xue
Mick Peterson
Rich Kimball
Acknowledgments
Geoff deBree
Raul Urbina
Tom McKay
ORPC, Jarlath McEntee
!"#$%&'()*##+,-+# //#
Questions
!"#$%&'()*##+,-+# //#
?