Engineering Flows in Small Devices: Microfluidics Toward a Lab-on-a-Chip

TLDR

Microfluidic devices manipulate fluids and are used widely across scientific and industrial contexts, requiring unusual geometries and the interplay of pressure gradients, electrokinetics, and capillarity, which give rise to variants of fluid dynamical problems and new fluid responses. The authors provide an overview of flows in microdevices, focusing on electrokinetics, mixing and dispersion, and multiphase flows. They highlight key aspects of fluid dynamics description, namely driving forces, geometry, and surface chemical characteristics.

Abstract

Microfluidic devices for manipulating fluids are widespread and finding uses in many scientific and industrial contexts. Their design often requires unusual geometries and the interplay of multiple physical effects such as pressure gradients, electrokinetics, and capillarity. These circumstances lead to interesting variants of well-studied fluid dynamical problems and some new fluid responses. We provide an overview of flows in microdevices with focus on electrokinetics, mixing and dispersion, and multiphase flows. We highlight topics important for the description of the fluid dynamics: driving forces, geometry, and the chemical characteristics of surfaces.