Experimental Study of Orientation Effects on Natural Convection Around New/Old LED Package

International audienceLight emitting diode (LED) light source is increasingly used for general lighting and seems to replace the fluorescent and incandescent source. However LED suffers from thermal problem. Thermal management of LED is essentially based on natural convection cooling. Experimental study of the orientation effects on the heat transfer of fin heat sink under natural convection conditions, for both new and old LED are carried out. The experimental results show that the horizontal upward is the best position for the heat sink to provide higher heat transfer rate. Comparison between the old and new LED is conducted and indicates that the new LED heats 10% more than the old LED in the case of vertical position. However, when turning off the lamp, the new one cools faster and better than the old one