otec heat exchangers: performance and power output...
TRANSCRIPT
Pat Grandelli, P.E. Steven Rizea, P.E. Michael Eldred Robert Loudon
OTEC Heat Exchangers: Performance and Power Output
for Historical and Modern Designs
Makai Ocean Engineering, Inc.
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Asia Pacific Clean Energy
Summit, OTEC Symposium
Honolulu, Hawaii September 2013
Heat Exchanger Attributes
•High heat transfer performance (U)
•Clean: Clog-free, no biofouling
•Corrosion: Lifetime
OTEC Heat Exchanger Development Focus
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•Cost: Materials & manufacturing
•Parasitic losses: Minimize flow & head
•Compactness: Manifolds, Area
Makai Ocean Engineering, Inc.
Initial Tests: 1978 - 79
Carnegie-Mellon Shell & Fluted Tube (Al)
Linde / Union Carbide Shell & Hi-Flux Tube (Ti) Plate Heat Exchanger (Ti) 3
Makai Ocean Engineering, Inc.
2nd Gen Tests: 1981
Johns Hopkins Folded Tube (Al)
Trane Brazed Aluminum Heat Exchanger #1
•By 1981, we learned cleanliness & biofouling are solvable. •Cost is the problem. Is aluminum the answer?
4 Makai Ocean Engineering, Inc.
3rd Gen Tests: 1981 - 84
Trane Brazed Aluminum Heat
Exchanger #2
•Corrosion & Fabrication •SW Flow & pressure ~30% less than CMU •Performance improved 6% vs. CMU •Gov’t funding ends
•BAHX2 is an improved OTEC Evaporator 5
Makai Ocean Engineering, Inc.
Recent Tests: 2012
BAHX3 is the result of OTEC plant system analysis.
L ifetime U (performance & parasitics) V alue (price & arrangement)
•BAHX3 has 2/3 of CMU flow, at same seawater head. •27% better U than CMU. • Extruded aluminum channels. • Vertical 5m tall. Compact.
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Makai Brazed Aluminum Heat
Exchanger #3
Makai Ocean Engineering, Inc.
Thank You References: • Avery, W.H. & Wu, C. Renewable Energy from the Ocean, A
Guide to OTEC. Oxford University Press, NY, 1994. • Constructability of extended surface heat exchangers for OTEC.
Proc. 8th Ocean Energy Conference. June 1981. • Makai Ocean Engineering, Chart Energy & Chemical Brazed
Aluminum Evaporator Testing Report, Aug 23, 2012. Unpublished.
• Panchal, CB. Heat transfer with Phase Change in Plate-Fin Heat Exchangers, Proc 22nd ASME-AICHE National Heat Transfer Conference, Niagara falls, NY, Aug 1984.
• Panchal, Hillis, et al. OTEC Performance tests of the Trane plate-fin heat exchanger. Argonne National laboratory report ANL/OTEC-PS-07. April 1981.
• Yung, Lorenz, et al. OTEC Performance tests of the Johns Hopkins University Applied Physics Laboratory Folded-Tube Heat Exchanger. Argonne National laboratory report ANL/OTEC-PS-09. August 1981.
Image citations: • Mini-OTEC: OTECnews.org • All other photos & graphs: Makai Ocean Engineering, Inc. • Trane Brazed Aluminum Heat Exchanger #1: Panchal, Hillis,
1981. • All other line art: Avery & Wu, 1994.
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Makai Ocean Engineering, Inc.
[email protected] (1) 808-259-8871 www.makai.com Makai Ocean Engineering, Inc.