Effect of thermal boundary conditions at the microscale: A means for flow generation and control

Abstract:

In difference from incompressible fluid flows, microscale gas flows commonly couple the dynamic and thermodynamic fluid states, through the combination of bulk-flow evolution and external boundary conditions. While thermal boundary conditions have a significant effect on the generated flows, traditional studies on rarefied gas systems have been limited to gas-surface interactions where the surfaces temperatures are prescribed. Such an assumption, however, may be of little practical value at unsteady conditions, where the surface temperature can only be imposed indirectly through direct prescription of the boundary heat-flux. In this talk, we demonstrate the impact of replacing an isothermal surface condition with a heat-flux condition in a variety of unsteady micro-flow setups. These include problems in acoustic wave propagation, active flow control, and shear-driven flows. Extensions to other setups, including hydrodynamic stability problems, are also reviewed.

Bio:

Avshalom Manela completed his BSc, MSc and PhD degrees in the Faculty of Aerospace Engineering at the Technion, Israel. During his PhD work, he examined the effects of gas rarefaction on the hydrodynamic stability of near-continuum gas flows. After completing his PhD, Dr. Manela accepted an Instructor position in the Department of Mathematics at MIT, where he conducted his post-doctoral research. In 2010, Dr. Manela joined the Faculty of Aerospace Engineering at the Technion, where he serves as an Assistant Professor. Dr. Manela's research interests combine topics in microfluidics, fluid structure interactions and acoustics.