Droplet formation in T-junction microchannel


  Droplet formation of a fluid in a second immiscible fluid has many practical applications in microfluidic such as biological processes, chemical analyses, drug delivery, heat exchangers etc. T-junction microchannels are used for droplets formation, fusion, fission and microscale mass transportation such as proteins. Droplet formation in a T-junction microfluidic device is simulated in five different regimes of squeezing, dripping, transition, jetting and parallel. Effects of Capillary number (Ca) and Reynolds number (Re) are investigated which changes the regime of droplet formation and creates rotational flow inside droplet, respectively. Simulations were done using Volume of Fluid (VOF) method and Adaptive Mesh Refinement (AMR) techniques in order to track interface properly. This study shows that the results of Re>1 have some differences compared with those of Re<1 . Using the effect of inertial forces, transition regime is limited to a range of Ca number. Simulations indicate that new vortices are created due to effect of inertial forces at a moment after droplet detachment, while it is fully creeping flow for Re<1. Springer Publishing. 2016. Meccanica. [http://dx.doi.org/10.1007/s11012-015-0245-6]