Ph.D. Proposal Presentation by
Peter T. Nagy
Wednesday, February 2, 2005
(Dr. Paul G. Neitzel, Chair)
"Investigation of Nonwetting System Failure and System Integration"
discovery of permanent suppression of coalescence and wetting has led researchers to investigate underlying mechanisms. Past studies concluded that a relative surface motion, introduced by the manipulation of surface tension force or by the translation of a droplet on another surface, drags the surrounding gas into the space between the surfaces in question. This flow of gas creates a thin film between the interfaces that acts a lubricant and inhibits the surfaces from coming into a contact. Surprisingly, these droplets defy their normal tendency to coalesce or wet permanently if proper conditions exist in providing the relative motion that supplies the film of gas. In addition, the noncoalescing and nonwetting droplets are able to withstand a compressive load.
Numerous engineering applications have been proposed to exploit the load-carrying and “non-contact” nature of noncoalescing and nonwetting systems. However, these droplets will fail by coalescing and wetting if proper conditions are not satisfied, e.g., if a large load is imposed or if external excitations are introduced. These failures must be well understood if engineers are to design a reliable system and operate it properly. The proposed research will investigate nonwetting system failures associated with an application of high static-loading and dynamic excitation. These studies will map out a reliable range of system operation that can be used to optimize system design. In addition, the nonwetting phenomenon will be exploited to levitate a drop for a microfluidic delivery system, which might one day be used in a “lab-on-a-chip” application.