Abstract
The capillary microseparator is an important microfluidic device for achieving the inline separation of biphasic segmented flows. While it has found wide applications in areas such as on-chip synthesis of pharmaceuticals and fine chemicals, many aspects regarding its operating ranges and hydrodynamic details remain to be elucidated. In this work, we employ OpenFOAM computational fluid dynamics (CFD) method to systematically simulate the performance of the capillary microseparator under the retention, normal operation and breakthrough regimes. The three distinct operating regimes are in accordance with experimental observations. In addition, the simulations enable quantification of the instantaneous flow rate through each micron-scale capillary microchannel and provide detailed predictions even under very low pressure differences (∼10 Pa), both of which are difficult to achieve experimentally. Furthermore, inspired by high-resolution hydrodynamics from the CFD simulations, we develop a simple analytic expression that predicts the retention threshold of the microseparator in good agreement with the simulated results and recent computations and experimental data.
Highlights
The segmented flow configuration exhibits enhanced heat and mass transfer performance owing to increased circulation and specific interfacial area, and has found many lab-on-chip applications, including multiphase reaction screening,[14] kinetics determination,[15] chemical synthesis,[16] crystallization,[17] extraction,[18,19] and microchemical assays.[20]
In order to obtain a better understanding of the underlying physics and enable accurate predictions, we systematically model the hydrodynamics of the device under various operating conditions using computational fluid dynamics (CFD) simulations, the volume-of-fluid (VOF) method
We systematically modelled the performance of the capillary microseparator using a combination of CFD simulations and analytical methods
Summary
Miniaturization of chemical processes via on-chip synthesis and manipulation has attracted considerable attention and undergone significant development in recent years.[1,2,3,4,5,6] In particular, the co-introduction of biphasic flow into a single microchannel gave rise to segmented flow, where droplets of the non-wetting phase are alternated between segments of the wetting fluid while moving concomitantly through a microchannel.[7,8,9,10,11,12,13] The segmented flow configuration exhibits enhanced heat and mass transfer performance owing to increased circulation and specific interfacial area, and has found many lab-on-chip applications, including multiphase reaction screening,[14] kinetics determination,[15] chemical synthesis,[16] crystallization,[17] extraction,[18,19] and microchemical assays.[20].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
