A review on the effects of porous coating surfaces on boiling heat transfer

Abstract

Nowadays, the heat transfer of surface material is a significant challenge faced by boiling and cooling industries. Therefore, several researchers are taking efforts to develop surface material coatings for enhancement of pool boiling. This paper provides a comprehensive review of previously published articles on the different surface coating materials used in boiling heat transfer enhancement and the various surface coating techniques employed for the development of the coating surfaces. Material coatings are covering thin film layers applied to metallic surfaces in various engineering applications to improve heat transfer performance. In addition, different types of coatings such as polymers, metals, ceramics and aerogels coatings applied on metal surfaces through different coatings techniques to enhance surface temperature are included. The rate of heat transfer during boiling depends upon the coating method and the properties of the surface material such as thermal conductivity, heating surface area, roughness and porosity. The surface modification using various material coating techniques results in the enhancement of the active nucleation site of the coating surface, which leads to an improvement of the critical heat flux (CHF) and the heat transfer coefficient (HTC). This is mainly due to increased surface temperature attained in the boiling prosses because of the high thermal conductivity of the surface coating materials. The current status of the surface coating techniques for boiling heat transfer along with their prevailing challenges, enhancement potentials and their possible industrial appliances are discussed in detail.