Wind Loads on Low-Profile, Tilted, Solar Arrays Placed on Large, Flat, Low-Rise Building Roofs
Publication: Journal of Structural Engineering
Volume 140, Issue 2
Abstract
The author examined wind loads on low-profile, roof-mounted solar arrays, placed on large, low-rise buildings with nearly flat roofs by using scale models in a boundary layer wind tunnel. The author also examined the effects of building size and array geometry on enveloping curves of area-averaged pressure coefficients, typical of use for design. It was found that wind loads on the array increase with building size; normalizing the effective wind area by the building wall size leads to enveloping curves that collapse onto a single curve for each array geometry. For tilt angles less than 10°, there is an approximate linear increase in the pressure coefficients as the tilt angle increases. For arrays with tilt angles of 10° or more, the wind loads do not depend significantly on the tilt angle and are relatively constant. Roof zones for wind loads on solar arrays are larger than roof zones for bare roofs and depend on the array tilt angle.
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Acknowledgments
SunLink Corporation funded this work. The author gratefully acknowledges the on-going support from Mr. Chris Tilley, Mr. Rob Ward, and Mr. Rod Holland. Univ. Machine Services of UWO manufactured the models used in this paper. The author is grateful to Mr. Steve Farquhar for conducting the experiments and helping with the data analysis. The author also acknowledges many useful conversations with Dr. David Banks of Cermak, Peterka, Peterson, Inc.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 140 • Issue 2 • February 2014
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Oct 4, 2012
Accepted: Feb 12, 2013
Published online: Feb 14, 2013
Published in print: Feb 1, 2014
Discussion open until: Mar 18, 2014
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