A Study on the Thermal Management of an LED Lamp Using Fin Heat Sinks

Autor: Christian Alvin, 廖文華
Rok vydání: 2012
Druh dokumentu: 學位論文 ; thesis
Popis: 100
High LED operational temperature should be considered. High power LED could generate more heat. Approximately 70-85% LED power is converted into heat. This high operating temperature of LED should be lowered, since high operating temperature will lead to reductions of the luminosity and the lifespan of LED. Many cooling system is used to dissipate heat from LED lamp. Most of the heat dissipation methods is using natural convection; by adding more areas to contact with the lower environment temperature. One effective way to increase the contact areas are by attached a heat sink to the heat source. Heat sink is easy to manufacture, relatively low in cost, light in weight, and can become an adequate cooling means with good reliability In this study, 10 Watt of LED lamp was used as a heat source for studying the effectiveness of extruded fin heat sink. The effectiveness was measured by the thermal resistance value between the LED and the heat sink. Lower thermal resistance value is needed for higher heat dissipation capability. Through the experiments, the effects of heat sink material, thermal interface material and heat sink mounting pressure on the thermal resistance value of the LED lamp system were investigated. Using statistical software Minitab 15, the significance of each factor can be determined. From this study it was shown that the thermal resistance was dominantly influenced by the heat sink mounting pressure, followed by the thermal interface materials and heat sink materials. Moreover, the effect of heat spreader to the heat sink resistance value was also investigated. Three types of heat spreader used in this study were: vapor chamber, copper block and aluminum block. Each of these heat spreaders was attached between the LED and extruded fin heat sink. The results show that vapor chamber is proven to be the most efficient heat spreader. Adding vapor chamber was increasing the heat sink heat dissipation performance, measured by having the lowest resistance value compared with using other types of heat spreader. Numerical simulations of ANSYS ICEPAK 12.1 were built to analyze the thermo-fluidic behavior of the LED lamp system and to visualize the temperature distribution of the system. It was found that the results obtained from numerical simulations were in good agreement with those obtained from the experimental data, with a percentage difference of equal or less than 10%. ANSYS ICEPAK 12.1 is also proven to be a suitable software for electronic cooling simulations.
Databáze: Networked Digital Library of Theses & Dissertations