Abstract
This study investigates the dynamic formation process of water microdroplets in a silicon oil flow in a T-junction microchannel. Segmented water microdroplets are formed at the junction when the water flow is perpendicularly injected into the silicon oil flow in a straight rectangular microchannel. This study further presents the effects of the water flow inlet geometry on hydrodynamic characteristics of water microdroplet formation. A numerical multiphase volume of fluid (VOF) scheme is coupled to solve the unsteady three-dimensional laminar Navier-Stokes equations to depict the droplet formation phenomena at the junction. Predicted results on the length and generated frequency of the microdroplets agree well with experimental results in a T-junction microchannel with straight and flat inlets (the base model) for both fluid flows. Empirical correlations are reported between the volumetric flow ratio and the dimensionless microdroplet length or dimensionless frequency of droplet generation at a fixed capillary number of 4.7 · 10−3. The results of this study indicate a reduction in the droplet length of approximately 21% if the straight inlet for the water flow is modified to a downstream sudden contraction inlet for the water flow.
Similar content being viewed by others
References
M. A. Burns, B. N. Johnson, S. N. Brahmasandra, et al., “An Integrated Nanoliter DNA Analysis Device,” Science 282, 484–487 (1998).
W. Wang, Z. X. Li, R. Luo, et al., “Droplet-Based Microoscillating-Flow PCR Chip,” J. Micromech. Microeng. 15, 1369–1377 (2005).
H. Song, J. D. Tice, and R. F. Ismagilov “A Microfluidic System for Controlling Reaction Networks in Time,” Angew. Chem. Int. Ed. 42, 768–772 (2003).
J. D. Tice, H. Song, A. D. Lyon, and R. F. Ismagilov, “Formation of Droplets and Mixing in Multiphase Microfluidics at Low Values of the Reynolds and the Capillary Numbers,” Langmuir. 19, 9127–9133 (2003).
H. Song, M. R. Bringer, J. D. Tice, et al., “Experimental Test of Scaling of Mixing by Chaotic Advection in Droplets Moving through Microfluidic Channels,” Appl. Phys. Lett. 83, 4664–4666 (2003).
J. D. Tice, A. D. Lyon, and R. F. Ismagilov, “Effects of Viscosity on Droplet Formation and Mixing in Microfluidic Channels,” Anal. Chim. Acta 507, 73–77 (2004).
S. M. S. Murshed, S. H. Tan, N. T. Nguyen, et al., “Microdroplet Formation of Water and Nanofluids in Heat-Induced Microfluidic T-Junction,” Microfluid Nanofluid 6, 253–259 (2009).
N. T. Nguyen, T. H. Ting, Y. F. Yap, et al., “Thermally Mediated Droplet Formation in Microchannels,” Appl. Phys. Lett. 91, 084102 (2007).
T. Thorsen, R. W. Roberts, F. H. Arnold, and S. R. Quakem, “Dynamic Pattern Formation in a Vesicle-Generating Microfluidic Device,” Phys. Rev. Lett., No. 6, 4163–4166 (2001).
P. Garstecki, M. J. Fuerstman, H. A. Stone, and G. M. Whitesides “Formation of Droplets and Bubbles in a Microfluidic T-Junction-Scaling and Mechanism of Break-Up,” Lab. Chip., No. 6, 437–446 (2006).
P. M. Korczyk, O. Cybulski, S. Makulska, and P. Garstecki, “Effects of Unsteadiness of the Rates of Flow on the Dynamics of Formation of Droplets in Microfluidic Systems,” Lab. Chip., No. 11, 173–175 (2011).
S. L. Anna, N. Bontoux, and H. A. Stone, “Formation of Dispersions Using’ Flow Focusing’ in Microchannels,” Appl. Phys. Lett. 82, 364–366 (2003).
P. Guillot and A. Colin, “Stability of Parallel Flows in a Microchannel after a T-Junction,” Phys. Rev. E 72, 066301 (2005).
V. van Steijn, C. R. Kleijn, and M. T. Kreutzer, “Predictive Model for the Size of Bubbles and Droplets Created in Microfluidic T-Junctions,” Lab. Chip., No. 10, 2513–2518 (2010).
A. J. Abrahamse, A. Van der Padt, R. M. Boom, and W. B. C. De Heij. “Process Fundamentals of Membrane Emulsification: Simulation with CFD,” AIChE J. 47, 1285–1291 (2001).
M. Rayner, G. Trägårdh, C. Trägårdh, and P. Dejmek, “Using the Surface Evolver to Model Droplet Formation Processes in Membrane Emulsification,” J. Colloid Interface Sci. 279, 75–185 (2004).
S. Van der Graaf, T. Nisisako, C. G. P. H. Schroën, et al., “Lattice Boltzmann Simulations of Droplet Formation in a T-Shaped Microchannel,” Langmuir 22, 4144–4152 (2006).
M. D. Menech, “Modeling of Droplet Break up in a Microfluidic T-Shaped Junction with a Phase-Field Model,” Phys. Rev. E 73, 031505 (2006).
L. Sang, Y. Hong, and F. Wang, “Investigation of Viscosity Effect on Droplet Formation in T-Shaped Microchannels by Numerical and Analytical Methods,” Microfluid Nanofluid, No. 6, 621–635 (2009).
S. Protiere, M. Z. Bazant, D. A. Weitz, and H. A. Stone, “Droplet Breakup in Flow Past an Obstacle: A Capillary Instability due to Permeability Variations,” Europhys. Lett. 92, 54002 (2010).
C. W. Hirt and B. D. Nichols, “Volume of Fluid (VOF) Method for the Dynamics of Free Boundaries,” J. Comput. Phys. 39, 201–225 (1981).
J. U. Brackbill, D. B. Kothe, and C. Zemach, “A Continuum Method for Modeling Surface Tension,” J. Comput. Phys. 100, 335–354 (1992).
D. L. Youngs, “Time-Dependent Multi-Lateral Flow with Large Fluid Distortion,” in Numerical Methods for Fluid Dynamics, Ed. by K. Baines and M. Morton (Academic Press, New York, 1982), pp. 273–285.
W. J. Rider and D. B. Kothe, “Reconstructing Volume Tracking,” J. Comput. Phys. 141, 112–152 (1998).
R. Dangla, F. Gallaire, and C. N. Baroud, “Microchannel Deformations due to Solvent-Induced PDMS Swelling,” Lab. Chip., No. 10, 2972–2978 (2010).
M. A. Holden, S. Kumar, A. Beskok, and P. S. Cremer, “Microfluidic Diffusion Diluter: Bulging of PDMS Microchannels under Pressure-Driven Flow,” J. Micromech. Microeng. 13, 412–418 (2003).
T. Gervais, J. El-Ali, A. Gunther, and K. F. Jensen, “Flow-Induced Deformation of Shallow Microfluidic Channels,” Lab. Chip., No. 6, 500–507 (2006).
B. S. Hardy, K. Uechi, J. Zhen, and H. P. Kavehpour, “The Deformation of Flexible PDMS Microchannels under a Pressure Driven Flow.” Lab. Chip., No. 9, 935–938 (2009).
R. Raj, N. Mathur, and V. V. Buwa, “Numerical Simulations of Liquid-Liquid Flows in Microchannels,” Indust. Engng Chem. Res. 49, 10606–10614 (2010).
H. Liu and Y. Zhang, “Droplet Formation in a T-Shaped Microfluidic Junction,” J. Appl. Phys. 106, 034906 (2009).
A. Gupta, S. M. S. Murshed, and R. Kumar, “Droplet Formation and Stability of Flows in a Microfluidic T-Junction,” Appl. Phys. Lett. 94, 164107 (2009).
Author information
Authors and Affiliations
Corresponding author
Additional information
Original Russian Text © F.L. Lih, J. M. Miao.
__________
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 56, No. 2, pp. 63–75, March–April, 2014.
Rights and permissions
About this article
Cite this article
Lih, F.L., Miao, J.M. Effect of junction configurations on microdroplet formation in a T-junction microchannel. J Appl Mech Tech Phy 56, 220–230 (2015). https://doi.org/10.1134/S0021894415020078
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S0021894415020078