MindTap Engineering for Dunlap's Sustainable Energy, SI Edition, 2nd Edition [Instant Access], 1 term (6 months)
2nd Edition
ISBN: 9781337551755
Author: DUNLAP
Publisher: Cengage Learning US
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A 2 x 2 m flat plate solar collector for domestic hot water heating is shown in the figure. The incident solar radiation on the glass cover, which transmits 90% of the incident flux, is 750 W/m2. Water flows through the tubes soldered to the backside of the absorber plate, entering at a temperature of 25°C. The temperature of the glass cover is 27°C, and it radiates heat with an emissivity of 0.92 to the sky at –50°C. Additionally, the glass cover losses heat by convection to air at 20°C flowing over its surface at 30 km/h. Assume that the radiation heat transfer between the absorber plate and glass cover and the heat transfer through the back and sides of the collector is negligible.
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MindTap Engineering for Dunlap's Sustainable Energy, SI Edition, 2nd Edition [Instant Access], 1 term (6 months)
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