Engineering Commons^™

Dynamic Wetting And Drag Reduction On Superhydrophobic And Liquid-Infused Surfaces, Jeong-Hyun Kim

Doctoral Dissertations

Reducing drag in fluid flow has been one of the most widely studied topics in fluid dynamics due to the significant impact on improving operational efficiencies and cutting cost in applications from the aerospace, automotive and naval industries. Over the past two decades, superhydrophobic surfaces have been in the spotlight due to their ability to reduce frictional drag on the wall surface in both laminar and turbulent flows. Despite the extensive work on superhydrophobic surfaces, there are still a number of open questions remaining. In this dissertation, we investigate how a moving contact line interacts with a superhydrophobic surface by …

The Microchannel Flow Of A Micropolar Fluid, Guohua Liu

Doctoral Dissertations

Micro-channel flows have been computed to investigate the influence of Navier-Stokes formulation for the slip-flow boundary condition, and a micro-polar fluid model, respectively.

The results of the slip boundary condition show that the current methodology is valid for slip-flow regime (i.e., for values of Knudsen number less than approximately 0.1). Drag reduction phenomena apparent in some micro-channels can be explained by slip-flow theory. These results are in agreement with some computations and experiments.

An ad hoc micro-polar fluid model is developed to investigate the influence of micro effects, such as micro-gyration, in micro-scale flows. The foundation of the ad hoc …