Particle manipulation using programmable hydrodynamic forces

Manipulating particles is of interest in diverse fields of engineering. Generally, manipulation activities carried out in micro-devices have a fixed design tailored to specific task. To address this issue, we designed a Hele-Shaw flow cell with "virtual" channels generated by uniform flow in transverse direction and three inlets in the longitudinal axis. These three inlets can inject or dispense fluid in the flow cell to deviate the streamlines. This device provides us the opportunity to integrate multiple functionalities such as particle trapping and separation onto a single device. Since the depth-averaged velocity over the channel in a Hele-Shaw cell is irrotational, we use potential flow theory to predict the flow field for manipulating particles.