Thermal management of square light emitting diode arrays: modeling and parametric analysis

• Published in: Multidiscipline modeling in materials and structures 2024-03, Vol.20 (2), p.363-383
• Main Author: Ben Hamida, Mohamed Bechir
• Format: Article
• Language: English
• Subjects: Arrays; Configurations; Cooling; Efficiency; Gallium arsenide; Heat; Heat conductivity; Heat sinks; Heat transfer; Light emitting diodes; Mathematical models; Optimization; Parametric analysis; Power; Temperature; Thermal management
• ISSN: 1573-6105; 1573-6113
• DOI: 10.1108/MMMS-09-2023-0311

PurposeThis study investigates the impact of three parameters such as: number of LED chips, pitch and LED power on the junction temperature of LEDs using a best heat sink configuration selected according to a lower temperature. This study provides valuable insights into how to design LED arrays with lower junction temperatures.Design/methodology/approachTo determine the best configuration of a heat sink, a numerical study was conducted in Comsol Multiphysics on 10 different configurations. The configuration with the lowest junction temperature was selected for further analysis. The number of LED chips, pitch and LED power were then varied to determine the optimal configuration for this heat sink. A general equation for the average LED temperature as a function of these three factors was derived using Minitab software.FindingsAmong 10 configurations of the rectangular heat sink, we deduce that the best configuration corresponds to the first design having 1 mm of width, 0.5 mm of height and 45 mm of length. The average temperature for this design is 50.5 C. For the power of LED equal to 50 W–200 W, the average temperature of this LED drops when the number of LED chips reduces and the pitch size decreases. Indeed, the best array-LED corresponds to 64 LED chips and a pitch size of 0.5 mm. In addition, a generalization equation for average temperature is determined as a function of the number of LED chips, pitch and power of LED which are key factors for reducing the Junction temperature.Originality/valueThe study is original in its focus on three factors that have not been studied together in previous research. A numerical simulation method is used to investigate the impact of the three factors, which is more accurate and reliable than experimental methods. The study considers a wide range of values for the three factors, which allows for a more comprehensive understanding of their impact. It derives a general equation for the average temperature of the LED, which can be used to design LED arrays with desired junction temperatures.