Transition from Threads to Droplets in a Microchannel for Liquids with No Viscosity Contrast

The flowing regime has a huge importance in microfluidics, mainly because every design can have its own flow map. However, the flowing regime differs from the case of macroscopic flows since we are in the case of confined flows, the material properties of the working fluids are at play, the aspect ratio and as well the actual design. In the current work we investigated the flowing regimes in a microchannel with three inlets using two immiscible liquids. Both fluids are Newtonian, a vegetal oil and a mixture of water and glycerol to match the viscosity of the vegetal oil. The purpose of this work is to investigate two flowing regimes: threading and dripping in terms of non-dimensional numbers and the transition between them.