Patterning Flows Using Grooved Surfaces: Application to Microfluidics

Pressure-driven flows over grooved surfaces are shown to develop transverse components. This induces helical recirculation in channels or capillaries with grooved walls, and more generally permits the design of 3D flows with simple patterns of grooved regions. This strategy is easy to implement with standard methods of microfabrication, and permits for example the realization of a low Reynolds number chaotic mixer.