Variations in convective venting to increase the efficiency of compact fluorescent downlights

The authors demonstrate 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 efficient downlight 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. The key issue in using convective venting as an effective thermal management technique is to maximize the thermal advantages of the venting configuration while reducing or eliminating the optical losses produced by openings in the envelop of the fixture or reflector. With the proper design and positioning of a convective venting geometry within a particular fixture, all of the benefits of a thermally efficient fixture can be obtained without compromise in optical efficiency