Experimental study on the heat transfer characteristics of flat-plate micro heat pipe arrays with grooved porous wick structure and porous copper foam inserts

The high-speed development of 5G technology and electronic components has provided an opportunity for micro heat pipe arrays (MHPAs). This study proposes a grooved multi-hole wick structure heat pipe (MHPA-CFW) with an MHPA micro-fin structure injected with copper foam to enhance the heat transfer performance. The study investigates how the heat transfer capability of MHPA-CFW is affected by the pore density and width of copper foam. It also examines its ability to function against gravity at various working inclinations. Experimental findings demonstrate that the MHPA-CFW exhibits superior heat transfer capability compared with that of MHPA. Under vertical operation, the heat transfer capability increases as the pore density rises at the low heat flux. However, it initially improves and then weakens with an increase in the pore density when the heat flux exceeds 3.75  W/cm². The heat transfer capability deteriorates as the copper foam width increases. A 4#MHPA-CFW (95PPI, 1.0 mm) was chosen for the multi-orientation experiment. Results indicate that it significantly enhances the heat transfer capability by overcoming the effects of gravity when the working inclination angle changes from 90° to −10°. These results provide a reference for improving heat transfer and expanding heat pipe applications in electronic heat dissipation.