This paper experimentally investigates the mechanism of water droplet detachment in a confined microchannel under highly inertial air flow. Experimental observations show that as the Reynolds number in the channel is increased, the droplet transitions from a nearly spherical droplet to a high aspect ratio slug. Scaling arguments are then made to address this behavior in an order of magnitude se...

We investigate the dynamics of a droplet on a planar substrate as the droplet volume changes dynamically due to liquid being pumped in or out through a pore. We adopt a diffuse-interface formulation which is appropriately modified to account for a localized inflow-outflow boundary condition (the pore) at the bottom of the droplet, hence allowing to dynamically control its volume, as the droplet...

This paper describes a multifunctional semi-closed droplet-array chip coupled with electrospray ionization mass spectrometry (ESI-MS) detection for multiple sample pretreatment and analysis. A novel interfacing method for coupling droplet system with ESI-MS was proposed using a sampling probe-two-dimensional (2D) droplet-array strategy. The 2D droplet-array system was composed of an 8 × 8 micro...

The behavior of droplets trapped in geometric structures is essential to droplet manipulation applications such as for droplet transport. Here we show that directional droplet movement can be realized by a V-shaped groove with the movement direction controlled by adjusting the surface wettability of the groove inner wall and the cross sectional angle of the groove. Experiments and analyses show...

ABSTRACT We describe an integrated microchip for droplet analysis with electrospray ionization mass spectrometry (ESI-MS). The chip integrated multiple modules of droplet generator, droplet extraction interface, and monolithic ESI-emitter. A novel droplet extraction interface based on a hydrophilic tongue structure was developed to transfer droplet from segmented phase to aqueous phase with hig...

Background: Several multiphase flow analyses have been developed to predict the fate of particles used in inhalation drug delivery; however, the collapse of droplets during their passage through respiratory tract has not been investigated. Objective: To assess the probability of droplet collapse in the upper respiratory tract.Methods: A 3D model of mouth-to-second generation airway after the tr...