Numerical investigation on the liquid-liquid, two phase flow in a Y-shaped microchannel

Abstract

A liquid-liquid, two phase, flow in a Y-shaped microchannel was numerically studied. Liquids 1~and~2, which are immiscible into each other, were injected into a Y-shaped microchannel from the two lateral channels respectively. The widths of the lateral and main channels are ten microns. The lengths of the lateral channels and main channel are five and 15 times of the channel width. The Volume of Fluid method was used to track the liquid-liquid interface, and Piecewise-Liner Interface Construction resolved a sharp interface. The interfacial tension was simulated with the Continuum Surface Force model with a wall adhesion boundary condition. The results show that a zebra flow mode appears in the main channel. For a certain inlet velocity, the length of zebra stripe depends on the interfacial tension force and inclined angles of two lateral channels. The length of a zebra stripe is short at large interfacial tension. As for the effect of confluent angles of Y-shaped junction, the zebra stripe length is largest when the inclined angles of two lateral channels are~$45^\circ$ and smallest when a T-shaped junction is used. References W. Ehrfeld, V. Hessel, and H. Lowe. Microreactors, New Technology for Modern Chemistry. WILEY-VCH Verlag GmbH, D-69469 Weinheim (Federal Republic of Germany), 2000. Harries, N., Burns, J. R., Barrow, D. A. and Ramshaw, C., A numerical model for segmented flow in a microreactor, International Journal of Heat and Mass Transfer, 46, 2003, 3313--3322. Tang, H., Wrobel, L. C. and Fan, Z., Tracking of immiscible interfaces in muitiple-material mixing processes, Computational Materials Science, 29, 2004, 103--118. Rider, W. J. and Kothe, D. B., Reconstrcting volume tracking, J. Comp. Phys. 141, 1998, 112--152. Brackbill, J. U., Kothe, D. B. and Zemach, C., A continuum method for modeling surface tension, J. Comp. Phys. 100, 1992, 335--354. V. Hessel, S. Hardt and H. Lowe. Chemical micro process engineering, Fundamentals, modelling and reactions. WILEY-VCH Verlag GmbH and Co.KGaA, Weinheim, 2004. Hirt, C. W. and Nichols, B. D., Volume of fluid (VOF) method for the dynamics of free boundaries, J. Comput. Phys. 39, 1981, 201--225. Youngs, D. L., Time-dependent multi-material flow with large fluid distortion, in: Numerical Methods for Fluid Dynamics, edited by K. W. Morton and M. J. Baines, Academic Press, New York, 1982, 273--285. C. W. Hirt, B. D. Nichols and N. C. Romero. SOLA: A numerical solution algorithm for transient fluid flow---Addendum. Los Alamos Scientfic Laboratory Report, LA-5852, 1975.