Abstract

The interface between air and water is a dynamic and complex environment where objects interact with surrounding fluids, exhibiting a wide range of hydrodynamic behaviors. Understanding these interactions is crucial for advancing fluid dynamics and has practical implications in fields such as maritime engineering and environmental science. Despite its importance, the study of objects partially immersed at the air-water interface has been limited due to the complex physics involved.

Our research investigates several key aspects of hydrodynamics at the air-water interface. We first examine the movement of floating spheres when pulled horizontally along the water surface, identifying distinct motion regimes that depend on the forces at play. Building on these findings, we explore the dynamics of buoyant spheres moving rapidly at the air-water interface, observing oscillations, air cavity formations, and skipping behavior. The interactions between the spheres and the water surface reveal complex fluid dynamics, including periodic diving and resurfacing, which influence the overall drag and lift forces experienced by the spheres.

We also investigate the effects of thin air layers, known as Leidenfrost vapor layers, on reducing drag for various objects moving through water. Although these layers significantly reduce drag for bluff bodies like spheres, their impact on streamlined objects is less pronounced, emphasizing the complex relationship between surface properties and fluid dynamics.

Additionally, we analyze the performance of hydrofoils and speed boats with superhydrophobic coatings. While these coatings reduce friction drag, they also introduce phenomena such as ventilated cavitation and increased splashing, which can affect overall performance.

Overall, our research enhances the understanding of hydrodynamics at the air-water interface, revealing complex interactions with significant implications for developing new technologies aimed at creating more efficient and innovative solutions for real-world applications.

Biography

Farrukh Kamoliddinov earned his B.Sc. (2016) and M.Sc. (2018) with honors from Lomonosov Moscow State University. He joined the High-Speed Fluids Imaging Laboratory as a Ph.D. student in the fall of 2019, under the supervision of Professor Sigurdur Thoroddsen. His research interests include fluid-solid interactions, multiphase flows, drag reduction, and flow instabilities.