Pool Boiling of CNT + GO Nanomaterial–Coated Copper Substrate: An Experimental Study

Abstract

Nanoparticle coating on copper substrates like carbon nanotubes (CNT) and graphene oxide (GO) is a promising method to enhance the surface properties as well as improve the boiling heat transfer characteristics. The main objective of the present investigation is to study the influence of the nanocomposite coating on the performance of pool boiling heat transfer. CNT + GO nanomaterials are coated on copper substrates via the dip coating method by varying the concentration of the nanomaterial. Morphological analysis, surface roughness, and wettability behavior of the coating are also observed. The result shows that CNT + GO increases the surface roughness of the samples, and the coated samples are superhydrophilic in nature. Compared with the uncoated sample, the coated sample shows the maximum increase in critical heat flux and heat transfer coefficient is 145.76% and 259.08%, respectively. A high-speed camera is used to study the bubble dynamics. Bubble diameter, departure frequency, and site density are also calculated and presented.