A microdevice for producing monodispersed droplets under a jetting flow

Abstract

A new microdevice by extending capillaries into a step microchannel for generating monodispersed droplets was specially designed. A much wider narrowing jetting flow regime can be easily realized in this new device.The new microchannel and the operating regime make it possible to produce monodispersed microdroplets that are one to two magnitudes smaller than the main channel size. Scaling laws of jet diameters and droplet sizes are developed in both theory and experiments. The device turns out to be a good platform for tiny droplet preparation under the jetting flow compared with conventional microchannels.

The dripping-to-jetting transition in a co-axial flow of aqueous two-phase systems with low interfacial tension

“…[1][2][3] The dynamics of the drippingto-jetting transition in co-axial ow is of fundamental importance in industrial applications that involve droplets. [4][5][6] Oilwater systems with a relatively high interfacial tension (g ¼ 0.1-40 mN m À1 ) are the main options to study the transition. Recently, some novel systems with a low interfacial tension, such as aqueous two-phase systems (ATPSs), are used to generate droplets and have great potential for applications in making bio-and cyto-compatible emulsion droplets.…”

Droplet formation of H2SO4/alkane system in a T‐junction microchannel: Gravity effect

“…Additionally, the effect of viscosity on the transition pattern is much greater than squeezing . Li et al found that the flow rate of the dispersed phase has little effect on the droplet size in dripping pattern while it has great influence on the jetting pattern . It is generally recognized that gravity has little effect on the droplet formation processes.…”

Manipulation and Control of Structure and Size of Inorganic Nanomaterials in Microchemical Systems

“…For example, droplets with a diameter of 0.7–10 μm could be produced based on phase change in a microfluidic platform with integrated heating and cooling modules . Moreover, Li et al successfully prepared small microbubbles of 35 μm and microdroplets of 15 μm by extending capillaries into a microchannel with a stair structure, while the bubble/droplet size is usually the same as that of the normal microchannels under dripping , , .…”