Water Entry Dynamics of Superhydrophobic and Lubricant-Impregnated Surfaces: A Theoretical and Experimental Perspective

In this current work, a comprehensive investigation into the impact dynamics of superhydrophobic and lubricant-impregnated aluminium sphere balls on liquid surfaces were carried out. The study delves into the hydrodynamic lubrication behavior and the resulting phenomena during impact. The Worthington jet and cavity associated give more insight into fundamental forces. The experimental analysis and theoretical modeling suggest potential applications in various fields such as fluid dynamics, tribology, and materials science. The stability investigation on an aluminum-textured sphere ball is carried out, and the evaluation of jet height and pinch-off phenomena is analyzed in detail. The experiment on entrapped air on a superhydrophobic surface and the oil inside the LIS for greater height was performed. The experimental setup involved a carefully designed apparatus for impact analysis by utilizing high-speed imaging techniques. Parameters such as impact velocity, Weber number, and sphere diameter were systematically varied to understand their influence on the observed dynamics. The lubricant viscosity is chosen such that it is comparable to water viscosity. Furthermore, the study on Lubricant Impregnated Surfaces (LIS) assessed frictional losses, i.e., drag reduction, compared to control and textured surfaces. In conclusion, the valuable insights into the impact dynamics advance our understanding of hydrodynamic lubrication and its applications. The findings presented here underscore the importance of further research in optimizing surface properties, selecting suitable lubricants, and exploring broader applications in the fields of fluid dynamics, surface engineering, and mechanical engineering.