Free-standing nanowire printed surfaces with high variability in substrate selection for boiling heat transfer enhancement

Nanowires (NWs) constitute a promising solution to the overheating of high-heat-load surfaces in mul-tiphase heat transfer. Typical nanostructure fabrication methods such as complex photolithography and metal-assisted chemical etching (MACE) that utilize patterned templates are limited by high manufactur-ing costs and type of substrate materials. These limitations significantly hinder the industrial applicability of NW structures in high heat flux units. In this study, we first examine the effect of the morphology of Zinc oxide (ZnO) NW printed substrates, fabricated via microcontact printing (mu CP) and solution based growing, on the heat transfer characteristics in pool boiling. Unlike advanced photolithography, mu CP offers greater vari-ability and convenience in terms of the substrate selection and large area creation for NW fabrication. Compared with the silicon substrate, the underlying mechanisms for enhancing both the critical heat flux and heat transfer coefficient of ZnO NW substrates are explored by analyzing the surface morphol-ogy, bubble, and wicking characteristics of the test surfaces, in order to determine the applicability of boiling heat transfer using ZnO NWs in industrial fields.(c) 2023 Elsevier Ltd. All rights reserved.

Automated summary

The effect of substrates with silicon base and zinc oxide nanowires on pool boiling heat transfer characteristics is investigated. The mechanisms for enhancing critical heat flux and heat transfer coefficient of zinc oxide nanowire substrates are explored by analyzing surface morphology, bubble, and wicking characteristics. The applicability of using zinc oxide nanowires for boiling heat transfer in industrial fields is determined.