Effect of Deficient Thermal Grease on the Junction Temperature of LEDs Package

K. B. Abdelmlek [1], Z. Araoud [1], K. Abderrazak [2], K. Charrada [1], G. Zissis [3]
[1] Unité d'Etude des Milieux Ionisés et Réactifs, Monastir, Monastir, Tunisia
[2] Unité de Thermique et Thermodynamique des Procédés Industriels, Monastir, Monastir, Tunisia
[3] Laboratoire Plasma et Conversion d'Énergie, Toulouse, France
Published in 2015

The use of LEDs package for lighting presents a thermal problem. In fact, 70% of the energy consumption is converted to heat. This affects widely the LEDs performance especially lifetime and luminous efficiency. Thermal management of LED is interested in natural convection cooling. The heat sink geometry and its design is important to ensure good heat transfer. Nevertheless, the control of the contact between heat sink and LED is essential to provide good cooling. In this work, we demonstrate that air layer thickness between heat sink and LED can decrease widely the heat transfer rate and participate on the lamp destruction.