Heat transfer analysis of a high-brightness LED array on PCB under different placement configurations

Predicting and estimating the thermal performance of a high-brightness LED array on PCB are critical to the effective integration of thermal management components in the assembly structure. Thermal performance and experimental verification of heat transfer via convection of a high-brightness LED array on PCB under different placement configurations were addressed in this study. The configuration design includes the change of thermal conductivity of the PCB materials and LED array placement method in a system module. The computational fluid dynamics method was used to simulate the heat transfer process of the LED array on PCB. Infrared camera and thermocouples are used to assess the thermal profile of the distribution of heat for the LED array on PCB in different specific regions. Using the developed placement configuration, the thermal distribution profile of a commercial high-brightness LED array on PCB was compared to that of conventional design. The output performance of the LED array was subsequently recorded in terms of the change in uniformity of illuminance, LED efficacy, and radiant flux. The new placement configuration for the LED array could be used to lower the individual LED temperature in the array by 26 °C and improve its luminous efficacy. The proposed LED placement configuration can thus provide the criteria for setting up a LED array system having an effective thermal management.