Field Testing of Wind Effects on Air-Cooled Condensers
Chuck McGowin, EPRI Kent Zammit, EPRIJohn Maulbetsch,
Maulbetsch Consulting
EPRI Workshop on Advanced Cooling Technologies
July 8-9, 2008, Charlotte, NC
2© 2008 Electric Power Research Institute, Inc. All rights reserved.
Wind Effects - A Recognized Problem for ACCs
• EPRI ACC Guidelines:– “…represents the major
challenge..with ACC specification, design and performance”
• Test codes---VGB, ASME, CTI– Average winds may not exceed
3 m/s– No gusts above 6 m/s (20 per
hour)
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Bighorn Power Plant
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Cell Layout and Instrumentation
4 3 2 1
Rows
A
B
North Cluster C
D Wind screen full height Wind screen lower 1/3
E Wind screen upper 2/3
RisersSteam duct
NF
G
SouthCluster H
I
J
Streets
1J
4I 3I 2I 1I
4J 3J 2J
4H 3H 2H 1H
4G 3G 2G 1G
4F 3F 2F 1F
4E 3E 2E 1E
4D 3D 2D 1D
4C 3C 2C 1C
1A
4B 3B 2B 1B
4A 3A 2A
X Fan shroud
Fan bridge
X
Fan motor
X Anemometers below fans
X
Temperature probe
X
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Southwestern Plant
Wind Effect
2
3
4
5
6
7
8
9
70 80 90 100 110 120
Ambient Temperature, F
Bac
kpre
ssur
e, in
Hga
0 to 4mph 4 to 8mph 8 to 12mph 12 to 16mph 16 to 20mph > 20mph
> 20 mph
0 to 4 mph
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Wind Effects on ACC Performance
•Recirculation•Fan performance degradation
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Recirculation
Where and how much?
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9© 2008 Electric Power Research Institute, Inc. All rights reserved.
Bighorn ACC Average Recirculation
0
1
2
3
4
5
6
7
8
6/10/05 6/11/05 6/12/05 6/13/05 6/14/05 6/15/05 6/16/05 6/17/05 6/18/05 6/19/05
Date
AC
C R
ecirc
ulat
ion,
FBighorn Average Recirculation June 10 to 18, 2005
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Cell 2I Inlet TemperatureHigh Winds; June 17--20:00h
3D 3C 3A 3B2D 2I 4A 2H 4H 4B 4F 4C 2J 4I 4G 3F 2C 2E 3I 2B 4D 3H 3G 2G 2F 2A 1I 1E
1F3E
1D 1A 3J 1C 4E1B
1H
1G
4J
1J
77
78
79
80
81
82
83
84
85
Cel
l Inl
et T
empe
ratu
res,
F
11© 2008 Electric Power Research Institute, Inc. All rights reserved.
Cell Velocity Averages--June 18
400
500
600
700
800
900
1,000
1,100
1,200
1,300
1,400
1,500
1,600
6/18/05 12:00PM
6/18/05 1:00PM
6/18/05 2:00PM
6/18/05 3:00PM
6/18/05 4:00PM
6/18/05 5:00PM
6/18/05 6:00PM
6/18/05 7:00PM
6/18/05 8:00PM
6/18/05 9:00PM
Date
Inle
t Vel
ocity
, fpm
Vely 3JAverage Vely 3IAverage Vely 3FAverage
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14© 2008 Electric Power Research Institute, Inc. All rights reserved.
Wind Screens
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Conclusions
Recirculation– “Zero wind inlet” temperature hard to define– Predominant at edge and corners downwind– Can be high in a few cells– JSM Opinion: Not very high on average---2 to 4 F
Fan Performance Degradation– Predominant in windward edge fans– Can be significant (50 – 70% reduction) in a few fans– JSM opinion: More important than recirculation
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Conclusions
Wind Screens– Good comparative field data not available– Anecdotal information:
• On a 5 x 6 ACC:– Helped with gusts– Not much effect on “steady state”
• On a 2 x 5 ACC (all edge cells):– Improved performance– Other changes at same time make comparison
difficult
