Synergistic effect of active-passive methods using fins surface roughness and fluid flow for improving cooling performance of heat sink heat pipes

The continued depreciation of electronic components presents severe challenges for thermal management. Regarding this issue, the current experimental study targets to propose and assess two passive cooling (using a heat sink and rough surface) and two active cooling (air and water cooling) for improving the cooling efficiency of aluminum heat sink heat pipes (HSHPs). In roughening process, the fins are chemically etched using a lab-made simple, cost-efficient, and environmental-friendly method to achieve better cooling performance synergistically. Scanning electron microscopy and atomic force microscopy characterizations are executed to investigate the heat sink surfaces' micro/nano roughened structure. Current results and related comparative studies of the three cooling modules (typical, liquid-based, and liquid-based micro/nano roughened HSHPs) are presented as well, where effects of constant/intermittent heat fluxes (4000-12000 W/m(2)) and the volume flow rates of testing fluid on heat transfer characteristics, thermal resistance, and temperature behavior are disclosed. Based on findings, at a constant heat flux, roughening the HSHP fins led to an enhancement in cooling through fins and a reduction in cooling through the water. Moreover, it is found that the modified HSHP without testing fluid and with water at volume flow rates of 100 and 200 ml/min decreases the thermal resistance by 11.9, 13.7, and 3.6%, in order, compared with the typical HSHP.