Microfluidics
Background
Microfluidic devices have existed in nature for millions of years. Indeed, the system that allows for oxygen exchange is a beautiful example of such a device [1]. More recently, with the advent of new technologies and development of soft materials, it has been possible to control flows at the microscale [2,3,4,5]. At this scale, fluids are primarily dominated by surface tension and viscous forces. The number that characterizes the competition between inertial and viscous forces in a fluid, the Reynolds number, is low [6]. This makes the description of these flows simpler. However, most microfluidic devices are built on top of a rigid substrate, making it impossible to study how the fluid-structure interactions may play a role in the fluid dynamics of the system. In this research we will aim to produce microfluidic devices that are supported in extremely flexible substrates and analyze the effects of elasticity [7] in the fluid flow at the microscale.
IRES student involvement
Students will be trained in the basics of fluid dynamics at the microscale in the first part of the internship. Students will explore different techniques aim to produce small and soft microfluidic devices, and will measure the different regimes that emerge at different flow rates in simple systems. They will learn how to use a high-speed camera and illumination techniques using laser sheets.
References
[1] Joseph A Potkay. The promise of microfluidic artificial lungs. Lab on a Chip, 2014.
[2] JC McDonald, GM Whitesides. Poly (dimethylsiloxane) as a material for fabricating microfluidic devices. Accounts of chemical research, 2002.
[3] TM Squires, SR Quake. Microfluidics: Fluid physics at the nanoliter scale. Reviews of modern physics, 2005.
[4] P Tabeling, S Chen. Introduction to Microfluidics. OUP Oxford, 2005.
[5] SN Bhatia, DE Ingber. Microfluidic organs-on-chips. Nature, 2014.
[6] C. Duprat, HA Stone. Fluid-Structure Interactions in Low-Reynolds-Number Flows. Royal Society of Chemistry, 2015.
[7] C Py, P Reverdy, L Doppler, J Bico, B Roman, C Baroud. “Capillary Origami: Spontaneous Wrapping of a Droplet with an Elastic Sheet”. Physical Review Letters, 2007