Droplet Dynamics in Microchannels

Droplet dynamics in microchannels refer to the description of motion and deformation of droplets in capillaries or conduits of hydraulic diameters of the orders of microns. 

Droplet Dynamics in Microchannels, Fig. 3 A schematic diagram specifying the contact angles at the rear and the front ends of the advancing droplet, alraig with the other pertinent geometrical features... 

Mathematical models for describing the droplet dynamics in microchannels can turn out to be substantially more involved in case the... 

Droplet Dynamics in Microchannels, Fig. 4 Critical conditions for droplet breaking at T-junctions... 

Droplet Dynamics in Microchannels, Figure 1 A deformable slug (droplet) in a micro-tube... 

Droplet Dynamics in Microchannels, Figure 2 A schematic layout of the analyzed microfluidic apparatus, showing the droplet of a liquid sandwiched between the electrodes and insulators... 

Mathematical models for describing the droplet dynamics in microchannels can turn out to be substantially more involved in case the multi-dimensionalities in the flow patterns need to be adequately resolved. One can demonstrate such a situation by describing the two-dimensional motion of a deformable droplet in a microchannel. The initial position and shape of the droplet are geometrically specified. Viscosity of the droplet is taken to be rn, and that of the continuous phase is taken to be ric- For simplicity, the density of the two phases is taken to be the same (= p). The equations governing the flow-field in the microchannel, in this case, can be described as... 

Another interesting feature of droplet dynamics in microchannels can be observed in the T-junctions, across which the droplets can be sheared, extended and split. In order to elucidate the underlying dynamics from a fundamental perspective, one may consider an underformed droplet (with viscosity r]iy) of radius / in a matrix fluid of viscosity r]c, with a local velocity gradient of magnitude G and surface tension y. The stresses scale as t]cG and the drop extension time-scale is as (1-f The sur-... 

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