Numerical and Experimental Study of Microdrops Flow-Selection by Fluidic Oscillator Device

Microdrops have been one of the most important branches in microfluidic science, Microfluidic oscillators were obtained from wall attachment microfluidic amplifiers using a feedback loop from the outputs to the control inputs [1], [2] have experimentally investigated the effects of the dimensions of the jet nozzle and feedback channel on the oscillatory frequency of water. In this work, we based on a feedback fluidic oscillator studied by [2], we perform numerical CFD study on the influence of hydrodynamics and physical parameters on the production of microdrops and its flow-separation, for that, we use the typical geometry, which includes double T-junction connected by a fluidic oscillator in order to produce simultaneous microdrops of oil on water. The generation of microdrops is computed by volume-of-fluid method (VOF). We investigated the microdrops frequencies as function of the difference of applied pressure ( P) and interfacial tension, flow oscillations of microdrops were triggered by the Coanda effect on jet flow, physical analysis of simulation results is also presented. The computational results show that the difference of applied pressure ( P) on T-junction and interfacial tension have a significant effect on the microdrops oscillatory frequency and its selection.