Anthony Goncalves
t3e Industrial research chair, École de technologie supårieure, Montråal, Canada
Daniel Rousse
t3e Industrial research chair, École de technologie supårieure, Montråal, Canada
Julien Milot
Energy Solutions Associates, Låvis, Canada
Ladda ner artikel
http://dx.doi.org/10.3384/ecp11057788Ingår i: World Renewable Energy Congress - Sweden; 8-13 May; 2011; Linköping; Sweden
Linköping Electronic Conference Proceedings 57:6, s. 788-795
Publicerad: 2011-11-03
ISBN: 978-91-7393-070-3
ISSN: 1650-3686 (tryckt), 1650-3740 (online)
With improved greenhouses; farmers have to ventilate. An air-to-air multi-tube counter flow heat exchanger unit was installed in a greenhouse used for the experimental cultivation of hydroponic tomatoes and cucumbers. This 24m long unit involves a 12” O.D. external shell used to exhaust moist air and five inner tubes to bring fresh air inside. The tests; carried out between March and May in a 576 m3 enclosure; demonstrated that average efficiencies of ?=84% and ?=78% were obtainable with air volumetric exchanges rates of 0.5 and 0.9 change per hour; respectively. Latent heat was found to play a major role in the overall heat transfer; contributing about 40% of the total energy exchanged in some situations. The exchanger could be buried underneath the ground or suspended above the crops. The unit made of plastic is durable; rot and rust resistant; affordable; and is ice and frost compliant. A pre commercial implementation with an improved design is now considered in collaboration with Gaz Metro. This paper presents the original prototype that help in reducing the consumption of natural gas; fuel; bunker; or propane.
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