AUTHORS: Abdelhakim Benali, Brahim Dennai, Rachid Khelfaoui
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ABSTRACT: Flows based on microfluidic oscillators are among the most studied flows in micro-system technology both because of their frequent occurrence in nature and their uses in many industrial applications. These flows have also been the subject of numerous academic studies because they generally have a simple geometry and can be considered as a vibratory system having a frequency and an amplitude which is represented by an injected mass flow. Most micro-mixers are often characterized by laminar flow and the effective mixing process is often difficult, many solutions are proposed in the literature to overcome this issue. As an example, effective mixing can be achieved by using a secondary pulsed flow to destabilize the diffusion layer between the two fluids to be mixed. This layer is then stretched and folded which leads to an improved chaotic mixture [1]. However, this technique requires specific actuation, making the micro system more complex and knives. In this work, our proposed idea is based on the use of unsteady movements generated by a micro-oscillator to hydrodynamically destabilize the diffusion layer between the two fluids to mix in a micromixer; we add that the design of this idea can be easily printed on a cheap and portable Micro fluidic chip. By talking about the large proportion of our work, we study an integrated micro-mixer with a micro-oscillator using a T-junction; several cases are studied numerically for liquid fluids using the CFD code. Practically, we want to follow numerically the variation of the efficiency of micro-mixer in parallel with the Change of the frequency of oscillator when injected the two fluids has mixed. This work has been developed at the level of the ENERGY laboratory in ARID Zones (ENERGARID)
KEYWORDS: micro fluidic, laminar flow, micro-oscillator, micro-mixer, T-junction
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