Performance comparative evaluation of three thin vapor chambers with different wick structures

Enhancing the performance of cooling modules is crucial for mitigating the heat dissipation problem of high-power-density electronic devices and simultaneously improving the energy efficiency of cooling systems. In this study, three 2-mm-thick vapor–liquid channel separation vapor chambers with different wick structures were fabricated. A novel radial-gradient sintered copper powder wick was firstly developed to improve the vapor–liquid conversion efficiency of working fluid, while the other two had homogeneous porosity wick structures with varying pore sizes. Experiments were systematically conducted with forced air cooling to comprehensively examine the effects of internal wick structures on heat transfer performance. The results indicated that the thermal performance of the vapor chamber can be improved by implementing the radial-gradient porosity wick. Specifically, the vapor chamber with a radial-gradient wick exhibited an improved thermal resistance of merely 0.052 °C/W, representing a 55.8% reduction in thermal resistance compared to a copper plate. Furthermore, when the improved vapor chamber was coupled with a heat sink to serve as the cooling module for a 100 W LED in practical applications, the operating temperature was kept below 49.4 °C. The proposed vapor chambers provide a highly efficient and reliable solution for thermal management in a wide range of applications.