Microscale Behaviors of Dropwise Condensation: Reflection Spectrum Analysis

The clustering phenomenon on the solid wall during dropwise condensation is analyzed with reflection spectrum. From the theoretical prediction of the reflectivity for thin liquid films with different thickness on stainless steel surface, it is ascertained that the reflectivity corresponds to the coacervate characteristics of the steam molecular. Furthermore, the experimental data of the reflection spectrum during dropwise condensation in literature also demonstrated that the reflection feature and so as the coacervate characters lie between liquid and steam after the droplet departing during an actual continuous condensation process. The clustering model is used to analyze the results, indicating that clusters form on the blank surface. And it is found that different microstructures of the solid wall would lead to different deposition rates of the clusters, which prompts an effective way to enhance heat transfer process of condensation by accelerating the deposition rate of clusters with surface modification.