An easily fabricated three-dimensional threaded lemniscate-shaped micromixer for a wide range of flow rates

Mehdi Rafeie, Marcel Welleweerd, Amin Hassanzadeh-Barforoushi, Mohsen Asadnia, Wouter Olthuis, Majid Ebrahimi Warkiani

    Research output: Contribution to journalArticleAcademicpeer-review

    20 Citations (Scopus)
    267 Downloads (Pure)

    Abstract

    Mixing fluid samples or reactants is a paramount function in the fields of micro total analysis system (μTAS) and microchemical processing. However, rapid and efficient fluid mixing is difficult to achieve inside microchannels because of the difficulty of diffusive mass transfer in the laminar regime of the typical microfluidic flows. It has been well recorded that the mixing efficiency can be boosted by migrating from two-dimensional (2D) to three-dimensional (3D) geometries. Although several 3D chaotic mixers have been designed, most of them offer a high mixing efficiency only in a very limited range of Reynolds numbers (Re). In this work, we developed a 3D fine-threaded lemniscate-shaped micromixer whose maximum numerical and empirical efficiency is around 97% and 93%, respectively, and maintains its high performance (i.e., >90%) over a wide range of 1 < Re < 1000 which meets the requirements of both the μTAS and microchemical process applications. The 3D micromixer was designed based on two distinct mixing strategies, namely, the inducing of chaotic advection by the presence of Dean flow and diffusive mixing through thread-like grooves around the curved body of the mixers. First, a set of numerical simulations was performed to study the physics of the flow and to determine the essential geometrical parameters of the mixers. Second, a simple and cost-effective method was exploited to fabricate the convoluted structure of the micromixers through the removal of a 3D-printed wax structure from a block of cured polydimethylsiloxane. Finally, the fabricated mixers with different threads were tested using a fluorescent microscope demonstrating a good agreement with the results of the numerical simulation. We envisage that the strategy used in this work would expand the scope of the micromixer technology by broadening the range of efficient working flow rate and providing an easy way to the fabrication of 3D convoluted microstructures.
    Original languageEnglish
    Article number014108
    Number of pages15
    JournalBiomicrofluidics
    Volume11
    Issue number1
    DOIs
    Publication statusPublished - 30 Jan 2017

    Fingerprint Dive into the research topics of 'An easily fabricated three-dimensional threaded lemniscate-shaped micromixer for a wide range of flow rates'. Together they form a unique fingerprint.

    Cite this