Advances in modeling investigations of multimode dropwise condensation heat transfer on smooth and textured surfaces – A review

Abstract

Manipulating dropwise condensation is of critical importance in enhancing liquid-gas phase change heat transfer. In addition to experimental investigations, theoretical modeling is also helpful in understanding the process of heat transfer in dropwise condensation. It has been over half a century since the very first theoretical model for dropwise condensation heat transfer. The essence of integrating the droplet heat transfer and droplet distribution is deeply rooted and long-lasting appreciated. In recent decades, the high-ended micro/nano-fabrication of the superhydrophobic textured surface has motivated both dropwise and jumping-droplet condensation heat transfer. Efforts have been made to understand and predict dropwise condensation or jumping-droplet condensation heat transfer by different models. However, the transient and random characteristics of self-propelled droplet jumping or sliding make it hard to establish a universal heat transfer model for all surfaces. In this review, we summarized the existing theoretical models for the multimode dropwise condensation on the smooth hydrophobic and textured superhydrophobic surfaces, including models for individual droplet heat transfer and droplet size distribution, to highlight the status-of-the-art. Comparisons with the experimental data under various conditions were provided. Some of the authors’ reflections were also presented, which are hoped to bring as many inspirations as possible to advances in the modeling work in the future.