Chemical Engineering Research & Design, Vol.102, 253-260, 2015
Development of bifurcation microchannel to uniformly distribute a liquid plug
This study developed a Y-bifurcation microchannel to enhance uniformity and reduce losses associated with the distribution of liquid plugs. Bifurcation geometry can be integrated within the design of high-throughput systems to enable the precise distribution of reagents used in parallel reactions. Numerical simulations were used to evaluate the geometry-dependent pressure distribution inside the splitting liquid plug, the results of which were used as a reference for the modification of the Y-bifurcation microchannels. Four geometries were tested in the simulations to elucidate the relationship between bifurcation geometry and distribution performance. A Y-bifurcation microchannel with rounded corners (2 mm radius) and a separator (0.5 mm in height) resulted in the smallest pressure difference within the splitting liquid plug. Thus, this design was adopted for the fabrication of devices used in subsequent experiments. The proposed Y-bifurcation microchannel was manufactured on a PMMA substrate using a micromilling machine in conjunction with a thermal bonding technique. The results of fifty experiments using the Y-bifurcation microchannel revealed an average variance of 2.13% (standard deviation of 3.94%) in distribution uniformity and an average residual liquid volume of 95% (standard deviation of 4.3%). The performance of the proposed Y-bifurcation microchannel proved significantly better than that of existing T-bifurcation microchannels. (C) 2015 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.
Keywords:Bifurcation microchannel;Uniform reagent distribution;ANOVA;Two phase flow numerical;Simulations;Microfluidics