Experimental study of nucleate pool boiling heat transfer improvement utilizing micro/nanoparticles porous coating on copper surfaces

Abstract

Abstract Pool boiling has gained tremendous attention in an efficient transferring of high thermal energy for diverse industrial applications. Surface coating is considered as a common approach for achieving an enhanced boiling heat transfer. In this paper, spin-coating technique is scrutinized experimentally for modifying the surface and enhancing the heat transfer in nucleate pool boiling of distilled water at atmospheric pressure. The images of Scanning Electron Microscopy (SEM) as well as Atomic Force Microscopy (AFM) are utilized for obtaining the phase structure and surface morphology in the prepared materials. Regarding the results of experimental tests, considerable improvements in surface roughness and porosity were achieved by the use of surface coating. Furthermore, the positive effect of adding an appropriate amount of material in achieving the enhanced overall performance of pool boiling was found. Also, higher nucleation sites densities (NSD) were formed by coating the surface, and consequently, improved boiling performance was reached. The maximum heat flux of 101.78 W/cm2 was associated with sample 4 regarding the highest roughness as well as the highest NSD. In addition, it was inferred that the superior surface characteristics of the micro/nanostructured coatings resulted in an enhanced heat transfer coefficient (HTC) value.