The effect of transverse spacing of a winglet pair on flat plate heat convection
Applied Thermal Engineering
The prevailing atmospheric wind can be manipulated to enhance the convective cooling of a solar photovoltaic panel and thus its energy conversion efficiency. The transverse spacing of a delta winglet pair was examined for its role in convective heat transfer enhancement. A pair of winglets with an inclination angle of 90° and a chord/height ratio of 2 was positioned at an attack angle of 30° with respect to incoming wind at a Reynolds number, based on the winglet height, of 6300. The transverse distance was varied from 0 to 3 winglet heights in 1 winglet height increments. The Nusselt number normalized by the reference no-winglet Nusselt number was determined from the surface temperature measured by a thermal camera. The two-height-spaced winglet pair was found to lead to the largest heat convection improvement. This significant heat transfer enhancement was explained in terms of vortical flow characteristics detailed at 10 winglet heights downstream of the winglet pair, where the most potent downwash was induced when the transverse spacing was 2 winglet heights.
Mohanakrishnan, Siddharth Koushik; Yang, Yang; Ting, David S.K.; and Ray, Steve. (2021). The effect of transverse spacing of a winglet pair on flat plate heat convection. Applied Thermal Engineering, 194.