Stationary Droplet Levitation via the Leidenfrost Effect: A Molecular Dynamics Study

Recent advances in microfluidic technology have positioned droplet-based systems as versatile microreactors, leveraging their unique interfacial dynamics and mass transfer properties. While precise manipulation of gas-liquid interfaces or external fields enables controlled chemical reactions and drug synthesis, escalating system complexity demands enhanced regulation of droplet thermodynamics and kinetics. The Leidenfrost phenomenon demonstrates significant engineering potential through its capacity to spontaneously form vapor lubrication layers, facilitating noncontact suspension and controlled evaporation of droplets. However, current research predominantly focuses on droplet impact behaviors with initial kinetic energy, leaving fundamental questions unresolved: Is kinetic energy conversion indispensable for this phenomenon? Can stationary droplets autonomously achieve stable levitation? In this context, this study employs molecular dynamics modeling to systematically investigate the phase transition behaviors of stationary droplets on high-temperature substrates. Our findings confirm the feasibility of Leidenfrost phenomenon formation under zero initial velocity conditions, while quantitatively elucidating the coupled effects of multiple physical parameters, including surface wettability, temperature, and droplet size. This work advances microscale phase-change theory and provides mechanistic insights for harnessing Leidenfrost effects in advanced manufacturing, including precision chemical engineering and biomedical applications.