"Nonlinear Stability of Interfacial Fluids in Microchannels" Entwicklung von numerischen und asymptotischen Modellen zur Beschreibung des Stabilitätsverhaltens von Grenzflächenströmungen in Mikrokanälen unter dem Einfluss von elektrischen Feldern.

• Applicant: Dr. Stefan Mählmann
• Subject Area: Fluid Mechanics
• Term: from 2006 to 2008
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 26314246

Liquid film flows occur in many applications of fluid mechanics including cooling systems, coating processes, combustion, and biological applications. The fundamental analysis of the stability and nonlinear states of such systems is of interest since the dynamics can enhance quantities such as heat and mass transfer rates. It is well known that electric fields can be used to control important physical aspects such as the properties of interfacial stability and the onset of singularities during rupture events. Although there have been numerous studies of the linear and nonlinear stability of interfacial flows in micro channels, research on the effects of electric fields acting on these flows is very rare. Recently, experiments at the NJIT have shown a nonlinear breakup mechanism in microchannel interfacial flow when an electric field acts on the fluids. Using finite electrodes, the flow can be controlled in a switching manner since the field produces instability. Detailed studies of the full problem have not been carried out so far. To improve understanding of the nonlinear stability of electrified microfluidic interfacial flows that cannot be addressed by asymptotic approaches, a full numerical simulation of the technically important electrified Poiseuille microchannel flow in a systematic way is proposed in this research. Special attention is devoted to interfacial stability, traveling wave formation, and droplet events.

• DFG Programme: Research Fellowships
• International Connection: USA
• Host: Professor Demitrios T. Papageorgiou