Droplet Impact on a Heated Surface: Influence of Key Factors on Heat Transfer

Abstract

The review focuses on the study of heat and mass transfer processes in liquid droplets, which play a critical role in various natural and technological systems. The main mechanisms of heat transfer and mass transport in droplets are considered, including convective and diffusive transport, evaporation, condensation, and interactions between the droplet and its surrounding environment. Unresolved challenges remain in deriving simplified estimates for unsteady, non-isothermal heat transfer in liquid droplets under rapidly changing boundary conditions on free surfaces. The review proposes several approaches to assess the intensity of heat and mass transfer. Factors influencing heat and mass transfer intensity, such as droplet size, temperature, liquid composition, gas properties, and external conditions, are analyzed. Theoretical approaches and models commonly used to describe these processes, as well as experimental research results, are presented. This review highlights the relevance of the problem and outlines prospects for further research into heat and mass transfer in droplets to improve technologies and deepen fundamental knowledge of interfacial processes. Understanding the physical mechanisms and accurately predicting droplet behavior and heat transfer are essential for advancing modern technologies, including materials science, spray cooling of microelectronics, inkjet printing, fuel droplet atomization in internal combustion engines, as well as applications in medicine (disease diagnostics) and biotechnology (micro- and mini-reactors).