Thermal Performance of a Vapor Chamber-Based Plate of High-Power Light-Emitting Diodes Filled with Al2O3 Nanofluid

Nanofluid that contains Al2O3 nanoparticles evenly dispersed in deionized water is considered to have superior heat transfer characteristics due to the significant increase in both collision frequency and contact surface area between the nanoparticles and the deionized water. The thermal performance of the vapor chamber-based plate of a high power light-emitting diode (LED) filled with Al2O3 nanofluid was experimentally investigated. The thermal characteristics of the vapor chamber were also compared with those of copper- and aluminum-based plates exposed to the heating source of four single-crystal LEDs. The experimental results show that the effective thermal conductivity of the vapor chamber increased with an increase in heat flux. A higher heating power caused an increase in the temperature variation in the vapor chamber, the illumination of the vapor chamber-, copper-, and aluminum-based plates, and the material resistance of the copper- and aluminum-based plates. In contrast, the spreading, convective, and total thermal resistance all decreased with an increase in heating power for all three base plates. The total thermal resistance of the vapor chamber is mostly due to its spreading thermal resistance, and appeared to be lower than that of the copper- and aluminum-based plates under a heating power of over 5 Watts.