Dispersion Behavior of a Droplet Impacting a Single Wetted Fiber

Abstract

The high-gravity reactor serves as a pivotal piece of equipment within the framework of high-gravity technology for CO2 capture. The phenomenon of droplet impact on wetted fibers is widely observed during the high-gravity decarbonization process. However, the underlying dynamics and subsequent dispersal characteristics that emerge following droplet impact on wetted fibers remain inadequately understood. In this work, the effects of initial velocity (u0), liquid film thickness (H), liquid film length (L), and impact eccentric distance (e) on the deformation evolution and dispersion characteristics of a droplet impacting a single wetted fiber were systematically studied. The observed deformation evolution process can be categorized into four distinct stages: contacting, merging-stretching, stretching-breaking, and rupture. Edge curling, elongated liquid threads, and liquid film tearing and rupture are commonly observed during the droplet impact process. Moreover, our findings indicate the existence of a critical velocity threshold that governs the behavior of droplets during their impact against wetted fibers. Following this analysis, we proposed a correlation for predicting the maximum rate of increase in the gas–liquid interfacial area of the droplet, demonstrating a high accuracy with errors confined to within ±20%. Furthermore, by examining the influences of differential pressure and velocity both within and external to the liquid film, we have developed a comprehensive understanding of the deformation mechanisms underlying droplet impacts on fiber surfaces.