Variations in Convective Venting to Increase the Efficiency of Compact Fluorescent Downlights

In most compact fluorescent recessed downlights, hot air stratifies within the fixture, causing the lamps to overheat and lose up to 25% of light output and efficacy. Thermal management techniques, including passive venting of the fixture, are being developed to mitigate these losses in fixture efficiency. This paper demonstrates a sequence of venting configurations and techniques, from an unmodified compact fluorescent downlight as a control fixture, through a series of venting strategies, to the development of a highly efficientsdownlight that incorporates a new angular concept in convective venting. With this new venting design, an increase in light output of nearly 25% can be attained without the optical losses generally associated with some venting geometries.