Analytical, numerical and experimental investigations of mixing fluids in microchannel

Abstract

This work presents theoretical analysis, numerical simulation, fabrication and test of a micromixer chip for mixing fluids in microchannel. A threedimensional analytical model is developed using a different mathematical approach to study passive laminar mixing phenomena and predict concentration distribution in a microchannel. The analytical model is validated by comparing with experimental and simulation results. The process of mixing fluids in a microchannel is simulated by solving the continuity, momentum and mass diffusion equations. The simulation results are validated and then parametric studies are performed to investigate the effects of channel aspect ratio, Reynolds number and diffusion coefficient on the mixing performance. The micromixer chip is fabricated with patterned SU-8 photoresist as the microchannel layer on a PMMA substrate using a combination of photolithography and micro-milling. Experiments are performed with different mixing fluids and the results were compared with that obtained from the theoretical model and simulation results.

Parametric investigation on mixing in a micromixer with two-layer crossing channels

“…Recently, computational fluid dynamics (CFD) has become very popular technique to analyze the mixing and fluid flow in micromixers. In recent years, many investigations have been performed to improve the mixing in a variety of passive micromixers; T-type micromixer (Gobby et al 2001 ) and Y-type micromixer (Sahu et al 2012 ), serpentine micromixers (Beebe et al 2001 ; Hossain et al 2009 ; Ansari and Kim 2009 ; Sahu et al 2013 ), split-and-recombinination (SAR) micromixers (Lee and Lee 2008 ; Viktorov and Nimafar 2013 ; Nimafar et al 2012a , b ; Hossain and Kim 2014 ), patterned grooves micromixers (Ansari and Kim 2007 ; Hossain et al 2010a , b ), etc. It was exposed that shifting the inlet direction in a T-type micromixer did not appreciably improve the mixing performance (Gobby et al 2001 ).…”

Nanofluidic mixing via hybrid surface

“…What is worth mentioning, previously reported micromixers have the typical mixing length of several to many millimeters 15 for moderate flow rates, and in a micromixer with hydrophobic/hydrophilic patterns only on the bottom wall of the microchannel, 16 effective mixing was observed after flowing for a distance of 20 mm in the microchannel. However, stable mixing phenomenon was clearly observed in only $300 lm in our design, which indicates a significant reduction in mixing length.…”

Development of a solenoid actuated planar valveless micropump with single and multiple inlet–outlet arrangements

“…A time-series of the mixing of two fluids inside the micropump chamber is depicted in figure 13. The mixing process is characterized in terms of a mixing index I m , which is defined as follows [49][50][51]…”