小曲率蛇形微通道弯头处弹状流流动及传质特性的数值研究

doi:10.11949/j.issn.0438-1157.20161283

摘要/Abstract

摘要：

采用CLSVOF（coupled level set and volume of fluid）方法，以空气和水为工作流体对小曲率矩形截面蛇形微通道内气液两相流动进行模拟研究。验证模型的合理性后，研究了曲率对弯通道内压降的影响，曲率及气相速度对弹状流气泡及液塞长度的综合影响；同时深入分析了弯管内气液两相流动的传质特性，包括不同曲率下气泡长度的变化，弯管内液侧体积传质系数与液膜体积传质系数的比较，曲率及气相速度对液相体积传质系数的影响。同时，对比了回转弯道与直微通道传质系数的差异，发现弯微通道可以强化传质。

关键词: 蛇形微通道, 气液两相流, 数值模拟, 微流体学, 弹状流

Abstract:

A numerical analysis of flow pattern in a serpentine microchannel with small curvature and rectangular cross-section was made using the CLSVOF(coupled level set and volume of fluid method) multiphase model.The gas and water were used as working fluids.After verifying the rationality of the model with the experiment, the effect of curvature on the pressure drop in curved microchannel was studied, the combined influence of curvature and gas velocity on bubble and liquid slug length were investigated.At the same time, the mass transfer characteristics of gas-liquid two-phase flow in curve microchannel were analyzed deeply, including the change of bubble length under different curvature, and comparison of liquid volumetric mass transfer coefficient and mass transfer coefficient of liquid film in curve microchannel.Also, effect of curvature and gas phase velocity on liquid phase volumetric mass transfer coefficient was observed.Meanwhile, the difference of mass transfer coefficient between the curve and straight microchannel was compared, which leaded to a conclusion that the curve micro-channel can enhance the mass transfer.

Key words: serpentine microchannels, gas-liquid flow, numerical simulation, microfluidics, slug flow

中图分类号:

TQ021.1

周云龙, 常赫. 小曲率蛇形微通道弯头处弹状流流动及传质特性的数值研究[J]. 化工学报, 2017, 68(1): 97-103.

ZHOU Yunlong, CHANG He. Numerical simulation on gas-liquid flow and mass transfer in curve part of serpentine micro-channel with small curvature[J]. CIESC Journal, 2017, 68(1): 97-103.

参考文献 30

[1]	叶仪, 殷晨波. Gauss型粗糙表面对微通道流动与换热的影响[J]. 农业机械学报, 2013, 44(12):294-300. YE Y, YIN C B. Effects of Gaussian rough surface on fluid flow and heat transfer in microchannels[J]. Transactions of Chinese Society for Agricultural Machinary, 2013, 44(12):294-300.
[2]	EHRFELD W, HESSEK V, LOWE H. Micro-reactors:New Technology for Modern Chemistry[M].Weinheim:WILEY-VCH, 2000:33-36.
[3]	FRIES D, VON R P R. Impact of inlet design on mass transfer in gas-liquid rectangular micro channels[J]. Microfluidics and Nanofluidics, 2009, 6(1):27-35.
[4]	TAN J, DU L, XU J H. Surfacant-free microdsipersion process of gas in organic solvents in microfluidic devices[J]. AIChE Journal, 2011, 57(10):2647-2656.
[5]	LEE C Y, LEE S Y. Influence of surface wettability on transition of two-phase flow pattern in round mini-channels[J]. International Journal of Multiphase Flow, 2008, 34(7):706-711.
[6]	TRIPLLET K A, GHIAASSIAAN S M, ABDEL-KHALIK S I, et al. Gas-liquid two-phase flow in microchannels(Ⅰ):Two -phase flow pattern[J]. International Journal of Multiphase Flow, 1999, 25(3):377-394.
[7]	MAS N D, JACKMAN R J, SCHMIDT M A, et al. Microchemical systems for direct fluorination of aromatics[C]//Fifth International Conference on Microreaction Technology (IMRET5). Berlin:Springer -Verlag, 2001:60-67.
[8]	ZHAO C X, MIDDLEBERG A P J. Two phase microfluidic flows[J]. Chemical Engineering Science, 2011, 66(7):1394-1411.
[9]	NIU H N, PAN L W, SU H J, et al. Flow pattern, pressure drop, and mass transfer in a gas-liquid concurrent two-phase flow microchannel reactor[J]. Industrial and Engineering Chemistry Research, 2009, 48(3):1621-1628.
[10]	AOKI N, TANGIWA S, MAE K. Design and operation of gas-liquid slug flow in a miniaturized channel for rapid mass transfer[J]. Chemical Engineering Science, 2011, 66(24):6536-6543.
[11]	DONALDSON A A, KIRPALANI D M, MACCHI A. Curvature induced flow pattern transitions in serpentine microchannels[J]. International Journal of Multiphase Flow, 2011, 37(8):429-439.
[12]	TRIPLLETE H A, KIM S. Microfluidics:basic issues, applications, and challenges[J]. AIChE Journal, 2001, 47(6):1250-1254.
[13]	AKIMI S, FENG Z P, ZENSAKU K. Two-phase flow in microchannels[J]. Experimental Thermal & Fluid Science, 2002, 26(6/7):703-714.
[14]	FRIES D M, WAELCHIL S, ROHR P R. Gas-liquid two-phase flow in meandering microchannels[J]. Chemical Engineering Journal, 2008, 135(S):S37-345.
[15]	WONG S H, WARD M C L, CHRISTOPHER C W. Micro T-mixer as a rapid mixing micromixer[J]. Sensors and Actuators B Chemical, 2004, 100(3):359-379.
[16]	PARK J M, KWON K Y. Numerical characterization of three-dimensional serpentine micromixers[J]. AICHE Journal, 2008, 54(54):1999-2008.
[17]	ANASARI M A, KIM K Y. Parametric study on mixing of two fluids in a three-dimensional serpentine microchannel[J]. Chem. Eng. J., 2009, 146(3):439-448.
[18]	SONG M, KIM H, KIM K. Effects of hydrophilic/hydrophobic prpperties of gas flow channels on liquid water transport in a serpentine polymer electrolyte membrane fuel cell[J]. Int. J. Hydrogen Energy, 2014, 39(7):19714-19721.
[19]	KOSITANONT C, PUTITISAK S, TAGAWA T. Multiphase parallel flow stabilization in curved microchannel[J]. Chemical Engineering Journal, 2014, 253(8):332-340.
[20]	周云龙, 常赫. 壁面润湿性对蛇形微通道内两相流流动特性影响的格子Boltzmann模拟[J]. 化工进展, 2016, 35(S1):20-25. ZHOU Y L, CHANG H. Lattice Boltzmann simulation of gas-liquid flow in serpentine microchannel under different contact angle[J]. Chemical Industry and Engineering Progress, 2016, 35(S1):20-25.
[21]	周云龙, 张立彦.矩形截面螺旋管内气液两相流型转换数值模拟[J]. 化工学报, 2014, 65(12):4767-4774. ZHOU Y L, ZHANG L Y. Numerical simulation of flow pattern transition for gas-liquid two-phase flow in helical square ducts[J]. CIESC Journal, 2014, 65(12):4767-4774.
[22]	周云龙, 孙振国. 蛇形微通道气液两相流动特性[J]. 化工学报, 2015, 66(11):4350-4358. ZHOU Y L, SUN Z G. Gas-liquid flow characteristics in serpentine micro channels[J]. CIESC Journal, 2015, 66(11):4350-4358.
[23]	ZHOU Y L, CHANG H, QI T Y. Gas-liquid two-phase flow in serpentine microchannel with different wall properties[J]. Chinese Journal of Chemical Engineering, doi:10.1016/j.cjche.2016.08.009.
[24]	SOBISESZUK P, CYGANSKI P, POHORECKI R.Bubble lengths in the gas-liquid Taylor flow in microchannels[J]. Chem. Eng. Res. Des., 2010, 88(5):263-269.
[25]	QIAN D, LAWAL A.Numerical study on gas and liquid slugs for Taylor flow in a T-junction microchannel[J]. Chem. Eng. Sci., 2006, 61(9):7609-7625.
[26]	PICARDO J R, PUSHPAVANAM S. Laterally stratified flow in a curved microchannel[J]. International Journal of Multiphase Flow, 2015, 75(3):39-53.
[27]	VANDU C O, LIU H, KRISNA R. Mass transfer from Taylor bubbles rising in single capillaries[J]. Chemical Engineering Science, 2005, 60(22):6430-6437.
[28]	VAN J M, KRISNA R. CFD simulations of mass transfer from Taylor bubbles rising in circular capillaries[J]. Chemical Engineering Science, 2004, 59(12):2535-2545.
[29]	YUE J, LUO L A, YVES G, et al. An experimental study of air-water Taylor flow and mass transfer inside square microchannels[J]. Chemical Engineering Science, 2009, 64(16):3697-3708.
[30]	孙俊杰, 郝婷婷, 马学虎, 等. 壁面润湿性对微通道内二氧化碳-水两相流流动及传质性能的影响[J]. 化工学报, 2015, 66(5):3405-3412. SUN J J, HAO T T, MA X H, et al. Surface wettability effect on carbon dioxide-water two-phase flow and mass transfer in rectangular microchannel[J]. CIESC Journal, 2015, 66(5):3405-3412.