Thermal transient analysis of LED array system with in-line pin fin heat sink

In this paper, a 3 W high power LED array system with an in-line pin fin heat sink is designed, fabricated, and investigated for thermal transient analysis. Preliminary finite element simulation is conducted by ANSYS, and LED array average junction temperature is about 40.9°C. In the experiment, electrical test method is used to evaluate the heat dissipation effect of the LED array system. Experiment results show that the system works well. The cumulative thermal resistance of the system is about 6.7K/W, and corresponding LED array average junction temperature is about 40.5°C. It is found that the simulation result is consistent with the experimental result. The error is about 1%. It is also found that, in order to get accurate thermal resistance of every kind of material in the heat flow path, we should analyze the curves of cumulative and differential structure function simultaneously.