Numerical Study of Flattened Miniature Heat Pipe with Hybrid Porous Wick and Double Heat Sources

Designing flattened miniature heat pipes (FMHPs) for electronic devices is a challenging issue due to high heat flux and limited heat dissipation space. It requires understanding the combined effects of the sintered-grooved wick structure, double heat sources, and flat thickness on heat pipes' thermal efficiency. Therefore, the aim of this study is to numerically investigate the effects of the FMHP with a hybrid wick on the thermal performance of its double heat sources acting as the CPU and GPU in notebook PCs. A transient 3D finite volume method was used to solve the governing equations and assisted boundary conditions. The cylindrical heat pipe with a 200 mm length and 6 mm outside diameter is flattened into 2, 2.5, 3, and 4 mm final thicknesses (FT). The obtained results show that the final critical thicknesses with the lowest thermal resistance are 2.5 and 3 mm for hybrid and grooved wick structures, respectively. Therefore, FMHP with hybrid wicks can be flattened about 8% more. Hybrid wick structures have the best effect on FMHP thermal performance at FT=2.5 mm