Research Papers: Fundamental Issues and Canonical Flows

Experimental Techniques for Bubble Dynamics Analysis in Microchannels: A Review

[+] Author and Article Information
Mahshid Mohammadi

e-mail: mohammma@onid.orst.edu

Kendra V. Sharp

Associate Professor
e-mail: kendra.sharp@oregonstate.edu
Department of Mechanical Engineering,
School of Mechanical, Industrial, and Manufacturing Engineering,
Oregon State University,
Corvallis, OR 97331

“High-speed” can be interpreted as thousands of frames per second; however, this term was also used in the cited literature for frame rates down to one hundred frames per second.

Manuscript received August 2, 2012; final manuscript received December 7, 2012; published online March 19, 2013. Assoc. Editor: David Sinton.

J. Fluids Eng 135(2), 021202 (Mar 19, 2013) (10 pages) Paper No: FE-12-1362; doi: 10.1115/1.4023450 History: Received August 02, 2012; Revised December 07, 2012

Experimental studies employing advanced measurement techniques have played an important role in the advancement of two-phase microfluidic systems. In particular, flow visualization is very helpful in understanding the physics of two-phase phenomenon in microdevices. The objective of this article is to provide a brief but inclusive review of the available methods for studying bubble dynamics in microchannels and to introduce prior studies, which developed these techniques or utilized them for a particular microchannel application. The majority of experimental techniques used for characterizing two-phase flow in microchannels employs high-speed imaging and requires direct optical access to the flow. Such methods include conventional brightfield microscopy, fluorescent microscopy, confocal scanning laser microscopy, and micro particle image velocimetry (micro-PIV). The application of these methods, as well as magnetic resonance imaging (MRI) and some novel techniques employing nonintrusive sensors, to multiphase microfluidic systems is presented in this review.

Copyright © 2013 by ASME
Your Session has timed out. Please sign back in to continue.


Lindken, R., Rossi, M., Große, S., and Westerweel, J., 2009, “Micro-Particle Image Velocimetry (µPIV): Recent Developments, Applications, and Guidelines,” Lab Chip, 9(17), pp. 2551–2567. [CrossRef] [PubMed]
Fu, T., Ma, Y., Funfschilling, D., and Li, H. Z., 2009, “Bubble Formation and Breakup Mechanism in a Microfluidic Flow-Focusing Device,” Chem. Eng. Sci., 64(10), pp. 2392–2400. [CrossRef]
Shui, L., Eijkel, J., and Vandenberg, A., 2007, “Multiphase Flow in Micro- and Nanochannels: A Review,” Sens. Actuators B, 121(1), pp. 263–276. [CrossRef]
Gunther, A., and Jensen, K. F., 2006, “Multiphase Microfluidics: From Flow Characteristics to Chemical and Materials Synthesis,” Lab Chip, 6(12), pp. 1487–1503. [CrossRef] [PubMed]
Yen, B. K. H., Günther, A., Schmidt, M. A., Jensen, K. F., and Bawendi, M. G., 2005, “A Microfabricated Gas–Liquid Segmented Flow Reactor for High-Temperature Synthesis: The Case of CdSe Quantum Dots,” Angew. Chem., 117(34), pp. 5583–5587. [CrossRef]
Yu, Z., Hemminger, O., and Fan, L., 2007, “Experiment and Lattice Boltzmann Simulation of Two-Phase Gas–Liquid Flows in Microchannels,” Chem. Eng. Sci., 62(24), pp. 7172–7183. [CrossRef]
Dietrich, N., Poncin, S., Midoux, N., and Li, H. Z., 2008, “Bubble Formation Dynamics in Various Flow-Focusing Microdevices,” Langmuir, 24(24), pp. 13904–13911. [CrossRef] [PubMed]
Hetsroni, G., 2003, “Two-Phase Flow Patterns in Parallel Micro-Channels,” Int. J. Multiphase Flow, 29(3), pp. 341–360. [CrossRef]
Wang, E., Devasenathipathy, S., Lin, H., Hidrovo, C., Santiago, J., Goodson, K., and Kenny, T., 2006, “A Hybrid Method for Bubble Geometry Reconstruction in Two-Phase Microchannels,” Exp. Fluids, 40(6), pp. 847–858. [CrossRef]
Cornwell, K., and Kew, P. A., 1993, “Boiling in Small Parallel Channels,” Energy Efficiency in Process Technology, P. A.Pilvachi, ed., Elsevier, London, pp. 624–638.
Kandlikar, S. G., 2004, “Heat Transfer Mechanisms During Flow Boiling in Microchannels,” ASME J. Heat Transfer, 126(1), pp. 8–16. [CrossRef]
Born, M., and Wolf, E., 1986, Principles of Optics, Pergamon Press, Oxford, UK, p. 415.
Meinhart, C. D., and Wereley, S. T., 2003, “The Theory of Diffraction-Limited Resolution in Microparticle Image Velocimetry,” Meas. Sci. Technol., 14(7), pp. 1047–1053. [CrossRef]
Piston, D. W., 1998, “Choosing Objective Lenses: The Importance of Numerical Aperture and Magnification in Digital Optical Microscopy,” Biol. Bull., 195(1), pp. 1–4. [CrossRef] [PubMed]
Thoroddsen, S. T., Etoh, T. G., and Takehara, K., 2008, “High-Speed Imaging of Drops and Bubbles,” Annu. Rev. Fluid Mech., 40, pp. 257–285. [CrossRef]
Takeuchi, H., Motosuke, M., and Honami, S., 2012, “Noncontact Bubble Manipulation in Microchannel by Using Photothermal Marangoni Effect,” Heat Transfer Eng., 33(3), pp. 234–244. [CrossRef]
Settles, G. S., 2001, Schlieren and Shadowgraph Techniques: Visualizing Phenomena in Transparent Media (Experimental Fluid Mechanics), R. J.Adrian, M.Gharib, W.Merzkirch, D.Rockwell, and J. H.Whitelaw, eds., Springer-Verlag, Berlin, pp. 28–32.
Lee, P. C., Tseng, F. G., and Pan, C., 2004, “Bubble Dynamics in Microchannels. Part I: Single Microchannel,” Int. J. Heat Mass Transfer, 47(25), pp. 5575–5589. [CrossRef]
Li, H. Y., Tseng, F. G., and Pan, C., 2004, “Bubble Dynamics in Microchannels. Part II: Two Parallel Microchannels,” Int. J. Heat Mass Transfer, 47(25), pp. 5591–5601. [CrossRef]
Feng, S. H., and Pan, C., 2005, “Bubble Dynamics in Multiple Parallel Silicon-Based Microchannels,” Proceedings of the 16th International Symposium on Transport Phenomena, Prague, Czech Republic.
Barber, J., Brutin, D., Sefiane, K., Gardarein, J. L., and Tadrist, L., 2011, “Unsteady-State Fluctuations Analysis During Bubble Growth in a ‘Rectangular’ Microchannel,” Int. J. Heat Mass Transfer, 54(23–24), pp. 4784–4795. [CrossRef]
Krishnamurthy, S., and Peles, Y., 2010, “Flow Boiling on Micropin Fins Entrenched Inside a Microchannel—Flow Patterns and Bubble Departure Diameter and Bubble Frequency,” ASME J. Heat Transfer, 132(4), p. 041002. [CrossRef]
Coleman, J. W., and Garimella, S., 1999, “Characterization of Two-Phase Flow Patterns in Small Diameter Round and Rectangular Tubes,” Int. J. Heat Mass Transfer, 42(15), pp. 2869–2881. [CrossRef]
Xu, J., Gan, Y., Zhang, D., and Li, X., 2005, “Microscale Boiling Heat Transfer in a Micro-Timescale at High Heat Fluxes,” J. Micromech. Microeng., 15(2), pp. 362–376. [CrossRef]
Fu, B. R., Lin, P. H., Tsou, M. S., and Pan, C., 2012, “Flow Pattern Maps and Transition Criteria for Flow Boiling of Binary Mixtures in a Diverging Microchannel,” Int. J. Heat Mass Transfer, 55(5–6), pp. 1754–1763. [CrossRef]
Galvis, E., and Culham, R., 2012, “Measurements and Flow Pattern Visualizations of Two-Phase Flow Boiling in Single Channel Microevaporators,” Int. J. Multiphase Flow, 42, pp. 52–61. [CrossRef]
Kandlikar, S. G., Kuan, W. K., Willistein, D. A., and Borrelli, J., 2006, “Stabilization of Flow Boiling in Microchannels Using Pressure Drop Elements and Fabricated Nucleation Sites,” ASME J. Heat Transfer, 128(4), pp. 389–396. [CrossRef]
Xu, J. H., Li, S. W., Wang, Y. J., and Luo, G. S., 2006, “Controllable Gas-Liquid Phase Flow Patterns and Monodisperse Microbubbles in a Microfluidic T-Junction Device,” Appl. Phys. Lett., 88(13), p. 133506. [CrossRef]
Garstecki, P., Fuerstman, M. J., Stone, H. A., and Whitesides, G. M., 2006, “Formation of Droplets and Bubbles in a Microfluidic T-Junction—Scaling and Mechanism of Break-Up,” Lab Chip, 6(3), pp. 437–446. [CrossRef] [PubMed]
Pancholi, K. P., Stride, E., and Edirisinghe, M. J., 2008, “Dynamics of Bubble Formation in Highly Viscous Liquids,” Langmuir, 24(8), pp. 4388–4393. [CrossRef] [PubMed]
Chen, C., Zhu, Y., Leech, P. W., and Manasseh, R., 2009, “Production of Monodispersed Micron-Sized Bubbles at High Rates in a Microfluidic Device,” Appl. Phys. Lett., 95(14), p. 144101. [CrossRef]
Wang, K., Lu, Y. C., Tan, J., Yang, B. D., and Luo, G. S., 2009, “Generating Gas/Liquid/Liquid Three-Phase Microdispersed Systems in Double T-Junctions Microfluidic Device,” Microfluid. Nanofluid., 8(6), pp. 813–821. [CrossRef]
Wang, K., Lu, Y. C., Xu, J. H., Tan, J., and Luo, G. S., 2011, “Generation of Micromonodispersed Droplets and Bubbles in the Capillary Embedded T-Junction Microfluidic Devices,” AIChE J., 57(2), pp. 299–306. [CrossRef]
Yun, J., Lei, Q., Zhang, S., Shen, S., and Yao, K., 2010, “Slug Flow Characteristics of Gas–Miscible Liquids in a Rectangular Microchannel With Cross and t-Shaped Junctions,” Chem. Eng. Sci., 65(18), pp. 5256–5263. [CrossRef]
Fu, T., Ma, Y., Funfschilling, D., Zhu, C., and Li, H. Z., 2010, “Squeezing-to-Dripping Transition for Bubble Formation in a Microfluidic T-Junction,” Chem. Eng. Sci., 65(12), pp. 3739–3748. [CrossRef]
Santos, R. M., and Kawaji, M., 2010, “Numerical Modeling and Experimental Investigation of Gas-Liquid Slug Formation in a Microchannel T-Junction,” Int. J. Multiphase Flow, 36(4), pp. 314–323. [CrossRef]
Gañán-Calvo, A. M., and Gordillo, J. M., 2001, “Perfectly Monodisperse Microbubbling by Capillary Flow Focusing,” Phys. Rev. Lett., 87(27), p. 274501. [CrossRef] [PubMed]
Gordillo, J. M., Cheng, Z., Ganan-Calvo, A. M., Márquez, M., and Weitz, D. A., 2004, “A New Device for the Generation of Microbubbles,” Phys. Fluids, 16(8), pp. 2828–2834. [CrossRef]
Garstecki, P., Ganan-Calvo, A. M., and Whitesides, G. M., 2005, “Formation of Bubbles and Droplets in Microfluidic Systems,” Bull. Pol. Acad. Sci.: Tech. Sci., 53(4), pp. 361–372. Available at http://www.ippt.pan.pl/~bulletin/%2853-4%29361.pdf
Garstecki, P., Gitlin, I., DiLuzio, W., Whitesides, G. M., Kumacheva, E., and Stone, H. A., 2004, “Formation of Monodisperse Bubbles in a Microfluidic Flow-Focusing Device,” Appl. Phys. Lett., 85(13), pp. 2649–2651. [CrossRef]
Dollet, B., van Hoeve, W., Raven, J.-P., Marmottant, P., and Versluis, M., 2008, “Role of the Channel Geometry on the Bubble Pinch-Off in Flow-Focusing Devices,” Phys. Rev. Lett., 100(3), p. 034504. [CrossRef] [PubMed]
Fu, T., Funfschilling, D., Ma, Y., and Li, H. Z., 2009, “Scaling the Formation of Slug Bubbles in Microfluidic Flow-Focusing Devices,” Microfluid. Nanofluid., 8(4), pp. 467–475. [CrossRef]
Xiong, R., Bai, M., and Chung, J. N., 2007, “Formation of Bubbles in a Simple Co-Flowing Micro-Channel,” J. Micromech. Microeng., 17(5), pp. 1002–1011. [CrossRef]
Quan, X., Chen, G., and Cheng, P., 2010, “Periodic Generation and Transport of Micro Air Bubble in Co-Flowing of Water in Microchannels,” Int. Commun. Heat Mass Transfer, 37(8), pp. 992–997. [CrossRef]
Shintaku, H., Imamura, S., and Kawano, S., 2008, “Microbubble Formations in MEMS-Fabricated Rectangular Channels: A High-Speed Observation,” Exp. Therm. Fluid Sci., 32(5), pp. 1132–1140. [CrossRef]
Sevilla, A., Gordillo, J. M., and Martinez-Bazan, C., 2005, “Bubble Formation in a Coflowing Air-Water Stream,” J. Fluid Mech., 530, pp. 181–195. [CrossRef]
Yue, J., Luo, L., Gonthier, Y., Chen, G., and Yuan, Q., 2008, “An Experimental Investigation of Gas–Liquid Two-Phase Flow in Single Microchannel Contactors,” Chem. Eng. Sci., 63(16), pp. 4189–4202. [CrossRef]
Yasuno, M., Sugiura, S., Iwamoto, S., Nakajima, M., Shono, A., and Satoh, K., 2004, “Monodispersed Microbubble Formation Using Microchannel Technique,” AIChE J., 50(12), pp. 3227–3233. [CrossRef]
Ichikawa, N., Chung, P., Matsumoto, S., Matsumoto, J.-I., and Takada, N., 2007, “Generation of Gas Bubbles in Microflow Using Micropipette With Ultrasound,” Microgravity Sci. Technol., 19(3), pp. 35–37. [CrossRef]
Barajas, A. B., and Panton, R. L., 1993, “Effects of Contact Angle on Two-Phase Flow in Capillary Tubes,” Int. J. Multiphase Flow, 19(2), pp. 337–346. [CrossRef]
Triplett, K. A., Ghiaasiaan, S. M., Abdel-Khalik, S. I., and Sadowski, D. L., 1999, “Gas-Liquid Two-Phase Flow in Microchannels Part I: Two-Phase Flow Patterns,” Int. J. Multiphase Flow, 25(3), pp. 377–394. [CrossRef]
Yang, C. Y., and Shieh, C. C., 2001, “Flow Pattern of Air-Water and Two-Phase R-134a in Small Circular Tubes,” Int. J. Multiphase Flow, 27(7), pp. 1163–1177. [CrossRef]
Haverkamp, V., Hessel, V., Lowe, H., Menges, G., Warnier, M. J. F., Rebrov, E. V., de Croon, M. H. J. M., Schouten, J. C., and Liauw, M. A., 2006, “Hydrodynamics and Mixer-Induced Bubble Formation in Micro Bubble Columns With Single and Multiple-Channels,” Chem. Eng. Technol., 29(9), pp. 1015–1026. [CrossRef]
Serizawa, A., Feng, Z., and Kawara, Z., 2002, “Two-Phase Flow in Microchannels,” Exp. Therm. Fluid Sci., 26(6–7), pp. 703–714. [CrossRef]
Cubaud, T., Ulmanella, U., and Ho, C.-M., 2006, “Two-Phase Flow in Microchannels With Surface Modifications,” Fluid Dyn. Res., 38(11), pp. 772–786. [CrossRef]
Fu, B. R., Tseng, F. G., and Pan, C., 2007, “Two-Phase Flow in Converging and Diverging Microchannels With CO2 Bubbles Produced by Chemical Reactions,” Int. J. Heat Mass Transfer, 50(1–2), pp. 1–14. [CrossRef]
Cubaud, T., and Ho, C. M., 2004, “Transport of Bubbles in Square Microchannels,” Phys. Fluids, 16(12), pp. 4575–4585. [CrossRef]
Sur, A., and Liu, D., 2012, “Adiabatic Air-Water Two-Phase Flow in Circular Microchannels,” Int. J. Therm. Sci., 53, pp. 18–34. [CrossRef]
Abadie, T., Aubin, J., Legendre, D., and Xuereb, C., 2012, “Hydrodynamics of Gas-Liquid Taylor Flow in Rectangular Microchannels,” Microfluid. Nanofluid., 12(1–4), pp. 355–369. [CrossRef]
Kawahara, A., Sadatomi, M., Nei, K., and Matsuo, H., 2009, “Experimental Study on Bubble Velocity, Void Fraction and Pressure Drop for Gas–Liquid Two Phase Flow in a Circular Microchannel,” Int. J. Heat Fluid Flow, 30(5), pp. 831–841. [CrossRef]
Zhao, T. S., and Bi, Q. C., 2001, “Co-Current Air–Water Two-Phase Flow Patterns in Vertical Triangular Microchannels,” Int. J. Multiphase Flow, 27(5), pp. 765–782. [CrossRef]
Kwak, Y., Pence, D., Liburdy, J., and Narayanan, V., 2009, “Gas–Liquid Flows in a Microscale Fractal-Like Branching Flow Network,” Int. J. Heat Fluid Flow, 30(5), pp. 868–876. [CrossRef]
Wang, Q., and Zhang, Y., 2011, “High Speed Stereoscopic Shadowgraph Imaging and Its Digital 3D Reconstruction,” Meas. Sci. Technol., 22(6), p. 065302. [CrossRef]
Voisin, C., Jeandet, P., and Liger-Belair, G., 2005, “On the 3D-Reconstruction of Taylor-Like Bubbles Trapped Inside Hollow Cellulose Fibers Acting as Bubble Nucleation Sites in Supersaturated Liquids,” Colloids Surf. A, 263, pp. 303–314. [CrossRef]
Blackmore, B., 2001, “Detachment of Bubbles in Slit Microchannels by Shearing Flow,” J. Colloid Interface Sci., 241(2), pp. 514–520. [CrossRef]
Chio, H., Jensen, M. J., Wang, X., Bruus, H., and Attinger, D., 2006, “Transient Pressure Drops of Gas Bubbles Passing Through Liquid-Filled Microchannel Contractions: An Experimental Study,” J. Micromech. Microeng., 16(1), pp. 143–149. [CrossRef]
Zhao, Y., and Cho, S. K., 2007, “Micro Air Bubble Manipulation by Electrowetting on Dielectric (EWOD): Transporting, Splitting, Merging and Eliminating of Bubbles,” Lab Chip, 7(2), pp. 273–280. [CrossRef] [PubMed]
Xu, J., Vaillant, R., and Attinger, D., 2010, “Use of a Porous Membrane for Gas Bubble Removal in Microfluidic Channels: Physical Mechanisms and Design Criteria,” Microfluid. Nanofluid., 9(4), pp. 765–772. [CrossRef]
Fu, B. R., and Pan, C., 2009, “Bubble Growth With Chemical Reactions in Microchannels,” Int. J. Heat Mass Transfer, 52(3–4), pp. 767–776. [CrossRef]
Borhani, N., Agostini, B., and Thome, J. R., 2010, “A Novel Time Strip Flow Visualisation Technique for Investigation of Intermittent Dewetting and Dryout in Elongated Bubble Flow in a Microchannel Evaporator,” Int. J. Heat Mass Transfer, 53(21–22), pp. 4809–4818. [CrossRef]
Ren, K. F., Gouesbet, G., Géhan, G., Lebrun, D., Özkul, C., and Kleitz, A., 1996, “On the Measurements of Particles by Imaging Methods: Theoretical and Experimental Aspects,” Part. Part. Syst. Charact., 13(2), pp. 156–164. [CrossRef]
Niwa, Y., Kamiya, Y., Kawaguchi, T., and Maeda, M., 2000, “Bubble Sizing by Interferometric Laser Imaging,” Proceedings of the 10th International Symposium on Applications of Laser Techniques to Fluid Mechanics, Lisbon, Portugal.
Maeda, M., Kawaguchi, T., and Hishida, K., 2000, “Novel Interferometric Measurement of Size and Velocity Distributions of Spherical Particles in Fluid Flows,” Meas. Sci. Technol., 11(12), pp. L13–L18. [CrossRef]
Kawaguchi, T., and Maeda, M., 2005, “Measurement Technique for Analysis in Two-Phase Flows Involving Distributed Size of Droplets and Bubbles Using Interferometric Method—Planar Simultaneous Measurement of Size and Velocity Vector Field,” Multiphase Sci. Technol., 17(1–2), pp. 57–77. [CrossRef]
Kawaguchi, T., Akasaka, Y., and Maeda, M., 2002, “Size Measurements of Droplets and Bubbles by Advanced Interferometric Laser Imaging Technique,” Meas. Sci. Technol., 13(3), pp. 308–316. [CrossRef]
Dehaeck, S., and van Beeck, J. P. A. J., 2008, “Multifrequency Interferometric Particle Imaging for Gas Bubble Sizing,” Exp. Fluids, 45(5), pp. 823–831. [CrossRef]
Hess, C., 1998, “Planar Particle Image Analyzer,” Proceedings of the 9th International Symposium on Applications of Laser Techniques to Fluid Mechanics, Lisbon, Portugal.
Dehaeck, S., van Beeck, J. P. A. J., and Riethmuller, M. L., 2005, “Extended Glare Point Velocimetry and Sizing for Bubbly Flows,” Exp. Fluids, 39, pp. 407–419. [CrossRef]
Dehaeck, S., Van Parys, H., Hubin, A., and van Beeck, J. P. A. J., 2009, “Laser Marked Shadowgraphy: A Novel Optical Planar Technique for the Study of Microbubbles and Droplets,” Exp. Fluids, 47(2), pp. 333–341. [CrossRef]
Sinton, D., 2004, “Microscale Flow Visualization,” Microfluid. Nanofluid., 1(1), pp. 2–21. [CrossRef]
Aubin, J., Ferrando, M., and Jiricny, V., 2010, “Current Methods for Characterising Mixing and Flow in Microchannels,” Chem. Eng. Sci., 65(6), pp. 2065–2093. [CrossRef]
Brown, C., 2007, “Fluorescence Microscopy—Avoiding the Pitfalls,” J. Cell Sci., 120(10), pp. 1703–1705. [CrossRef] [PubMed]
Gunther, A., Khan, S. A., Thalmann, M., Trachsel, F., and Jensen, K. F., 2004, “Transport and Reaction in Microscale Segmented Gas-Liquid Flow,” Lab Chip, 4(4), pp. 278–286. [CrossRef] [PubMed]
Waelchli, S., and Rudolf von Rohr, P., 2006, “Two-Phase Flow Characteristics in Gas-Liquid Microreactors,” Int. J. Multiphase Flow, 32(7), pp. 791–806. [CrossRef]
Fries, D. M., Trachsel, F., and von Rohr, P. R., 2008, “Segmented Gas-Liquid Flow Characterization in Rectangular Microchannels,” Int. J. Multiphase Flow, 34(12), pp. 1108–1118. [CrossRef]
Weinmueller, C., Hotz, N., Mueller, A., and Poulikakos, D., 2009, “On Two-Phase Flow Patterns and Transition Criteria in Aqueous Methanol and CO2 Mixtures in Adiabatic, Rectangular Microchannels,” Int. J. Multiphase Flow, 35(8), pp. 760–772. [CrossRef]
Yamaguchi, E., Smith, B. J., and Gaver, D. P., 2009, “μ-PIV Measurements of the Ensemble Flow Fields Surrounding a Migrating Semi-Infinite Bubble,” Exp. Fluids, 47(2), pp. 309–320. [CrossRef] [PubMed]
Meng, L., Cai, F., Jin, Q., Niu, L., Jiang, C., Wang, Z., Wu, J., and Zheng, H., 2011, “Acoustic Aligning and Trapping of Microbubbles in an Enclosed PDMS Microfluidic Device,” Sens. Actuators B, 160(1), pp. 1599–1605. [CrossRef]
Hellman, A. N., Rau, K. R., Yoon, H. H., Bae, S., Palmer, J. F., Phillips, K. S., Allbritton, N. L., and Venugopalan, V., 2007, “Laser-Induced Mixing in Microfluidic Channels,” Anal. Chem., 79(12), pp. 4484–4492. [CrossRef] [PubMed]
Claxton, N. S., Fellers, T. J., and Davidson, M. W., 2006, “Laser Scanning Confocal Microscopy,” Department of Optical Microscopy and Digital Imaging, Florida State University, Tallahassee, http://www.olympusconfocal.com/theory/LSCMIntro.pdf
Ferrando, M., and Spiess, W. E. L., 2000, “Review: Confocal Scanning Laser Microscopy—A Powerful Tool in Food Science,” Food Sci. Technol. Int., 6(4), pp. 267–284. [CrossRef]
Kihm, K. D., Kim, H.-J., Park, J.-S., Banerjee, A., Wee, S.-K., Choi, C.-K., Paik, S.-W., Seo, C.-S., and Lee, H.-J., 2004, “Development of Microscale Visualization Techniques,” J. Flow Visualization Image Process., 11(3), pp. 153–176. [CrossRef]
Park, J. S., Kihm, K. D., and Allen, J. S., 2002, “Three-Dimensional Microfluidic Measurements Using Optical Sectioning by Confocal Microscopy: Flow Around a Moving Air Bubble in a Micro-Channel,” Proceedings of the 2002ASME International Mechanical Engineering Congress and Exposition, ASME, New York, pp. 217–222. [CrossRef]
Park, J. S., Choi, C. K., and Kihm, K. D., 2004, “Optically Sliced Micro-PIV Using Confocal Laser Scanning Microscopy (CLSM),” Exp. Fluids, 37(1), pp. 105–119. [CrossRef]
Santiago, J. G., Wereley, S. T., Meinhart, C. D., Beebe, D. J., and Adrian, R. J., 1998, “Particle Image Velocimetry System for Microfluidics,” Exp. Fluids, 25(4), pp. 316–319. [CrossRef]
Meinhart, C. D., Wereley, S. T., and Santiago, J. G., 1999, “PIV Measurements of a Microchannel Flow,” Exp. Fluids, 27(5), pp. 414–419. [CrossRef]
Meinhart, C. D., Wereley, S., and Gray, M., 2000, “Volume Illumination for Two-Dimensional Particle Image Velocimetry,” Meas. Sci. Technol., 11(6), pp. 809–814. [CrossRef]
Bayraktar, T., and Pidugu, S. B., 2006, “Characterization of Liquid Flows in Microfluidic Systems,” Int. J. Heat Mass Transfer, 49(5–6), pp. 815–824. [CrossRef]
Lindken, R., and Merzkirch, W., 2002, “A Novel PIV Technique for Measurements in Multiphase Flows and Its Application to Two-Phase Bubbly Flows,” Exp. Fluids, 33(6), pp. 814–825. [CrossRef]
Yoon, S. Y., Kim, J. M., Kim, S. H., and Kim, K. C., 2004, “Micro-LIF Measurement in a Micro-Channel Using an Ultra-Thin Laser Light Sheet,” Proceedings of the 2004 ASME International Mechanical Engineering Congress and Exposition (IMECE 2004), ASME, New York, pp. 349–355. [CrossRef]
Yoon, S. Y., Ross, J. W., Mench, M. M., and Sharp, K. V., 2006, “Gas-Phase Particle Image Velocimetry (PIV) for Application to the Design of Fuel Cell Reactant Flow Channels,” J. Power Sources, 160(2), pp. 1017–1025. [CrossRef]
Fu, T., Ma, Y., Funfschilling, D., and Li, H. Z., 2011, “Dynamics of Bubble Breakup in a Microfluidic T-Junction Divergence,” Chem. Eng. Sci., 66(18), pp. 4184–4195. [CrossRef]
Kwak, Y., Liburdy, J., Pence, D., and Narayanan, V., 2007, “Liquid and Gas Phase Velocity Measurements for Two Phase Flow in a Branching Microchannel Network,” Proceedings of the ASME International Mechanical Engineering Congress and Exposition (IMECE 2007), ASME, New York, pp. 791–800. [CrossRef]
Vansteijn, V., Kreutzer, M., and Kleijn, C., 2007, “μ-PIV Study of the Formation of Segmented Flow in Microfluidic T-Junctions,” Chem. Eng. Sci., 62(24), pp. 7505–7514. [CrossRef]
Tseng, F. G., Yang, I. D., Lin, K. H., Ma, K. T., Lu, M. C., Tseng, Y. T., and Chieng, C. C., 2002, “Fluid Filling Into Micro-Fabricated Reservoirs,” Sens. Actuators, 97–98, pp. 131–138. [CrossRef]
Elcock, D., Jung, J., Kuo, C. J., Amitay, M., and Peles, Y., 2011, “Interaction of a Liquid Flow Around a Micropillar With a Gas Jet,” Phys. Fluids, 23(12), p. 122001. [CrossRef]
Fries, D. M., and von Rohr, P. R., 2009, “Liquid Mixing in Gas-Liquid Two-Phase Flow by Meandering Microchannels,” Chem. Eng. Sci., 64(6), pp. 1326–1335. [CrossRef]
Fries, D. M., Waelchli, S., and Rudolf von Rohr, P., 2007, “Gas-Liquid Two-Phase Flow in Meandering Microchannels,” Chem. Eng. J., 135(Suppl. 1), pp. S37–S45. [CrossRef]
Devasenathipathy, S., Santiago, J. G., Wereley, S. T., Meinhart, C. D., and Takehara, K., 2003, “Particle Imaging Techniques for Microfabricated Fluidic Systems,” Exp. Fluids, 34(4), pp. 504–514. [CrossRef]
Park, J. S., and Kihm, K. D., 2006, “Three-Dimensional Micro-PTV Using Deconvolution Microscopy,” Exp. Fluids, 40(3), pp. 491–499. [CrossRef]
Mantle, M. D., Sederman, A. J., Gladden, L. F., Raymahasay, S., Winterbottom, J. M., and Stitt, E. H., 2002, “Dynamic MRI Visualization of Two-Phase Flow in a Ceramic Monolith,” AIChE J., 48(4), pp. 909–912. [CrossRef]
Gladden, L. F., Lim, M. H. M., Mantle, M. D., Sederman, A. J., and Stitt, E. H., 2003, “MRI Visualisation of Two-Phase Flow in Structured Supports and Trickle-Bed Reactors,” Catal. Today, 79–80, pp. 203–210. [CrossRef]
Sederman, A. J., Mantle, M. D., and Gladden, L. F., 2003, “Single Excitation Multiple Image RARE (SEMI-RARE): Ultra-Fast Imaging of Static and Flowing Systems,” J. Magn. Res., 161(1), pp. 15–24. [CrossRef]
Sederman, A. J., Heras, J. J., Mantle, M. D., and Gladden, L. F., 2007, “MRI Strategies for Characterising Two-Phase Flow in Parallel Channel Ceramic Monoliths,” Catal. Today, 128(1–2), pp. 3–12. [CrossRef]
Heras, J. J., Sederman, A. J., and Gladden, L. F., 2005, “Ultrafast Velocity Imaging of Single- and Two-Phase Flows in a Ceramic Monolith,” Magn. Reson. Imaging, 23(2), pp. 387–389. [CrossRef] [PubMed]
Kraus, T., Gunther, A., Mas, N., Schmidt, M. A., and Jensen, K. F., 2004, “An Integrated Multiphase Flow Sensor for Microchannels,” Exp. Fluids, 36(6), pp. 819–832. [CrossRef]
De Mas, N., Gunther, A., Kraus, T., Schmidt, M. A., and Jensen, K. F., 2005, “Scaled-Out Multilayer Gas-Liquid Microreactor With Integrated Velocimetry Sensors,” Ind. Eng. Chem. Res., 44(24), pp. 8997–9013. [CrossRef]
Leung, S.-A., Edel, J. B., Wootton, R. C. R., and deMello, A. J., 2004, “Continuous Real-Time Bubble Monitoring in Microchannels Using Refractive Index Detection,” Meas. Sci. Technol., 15(1), pp. 290–296. [CrossRef]
Wolffenbuttel, B. M. A., Nijhuis, T. A., Stankiewicz, A., and Moulijn, J. A., 2002, “Novel Method for Non-Intrusive Measurement of Velocity and Slug Length in Two- and Three-Phase Slug Flow in Capillaries,” Meas. Sci. Technol., 13(10), pp. 1540–1544. [CrossRef]
Revellin, R., Agostini, B., and Thome, J. R., 2008, “Elongated Bubbles in Microchannels. Part II: Experimental Study and Modeling of Bubble Collisions,” Int. J. Multiphase Flow, 34(6), pp. 602–613. [CrossRef]
Revellin, R., Agostini, B., Ursenbacher, T., and Thome, J. R., 2008, “Experimental Investigation of Velocity and Length of Elongated Bubbles for Flow of R-134a in a 0.5 mm Microchannel,” Exp. Therm. Fluid Sci., 32(3), pp. 870–881. [CrossRef]
Revellin, R., Dupont, V., Ursenbacher, T., Thome, J. R., and Zun, I., 2006, “Characterization of Diabatic Two-Phase Flows in Microchannels: Flow Parameter Results for R-134a in a 0.5 mm Channel,” Int. J. Multiphase Flow, 32(7), pp. 755–774. [CrossRef]
Revellin, R., and Thome, J. R., 2007, “Optical Measurements to Characterize Two-Phase Fluid Flow in Microchannels,” Multiphase Sci. Technol., 19(1), pp. 75–97. [CrossRef]


Grahic Jump Location
Fig. 1

Schematic of shadowgraphy for a gas bubble in a liquid medium, adapted from Settles [17]

Grahic Jump Location
Fig. 2

Principles of GPVS and ILIDS techniques, courtesy of Dehaeck and van Beeck [76]

Grahic Jump Location
Fig. 3

Arrangement of the filters in a widefield fluorescent microscope with xenon/mercury arc light source

Grahic Jump Location
Fig. 4

Fluorescent images from different flow patterns in microchannels, (a) slug and plug flow, (b) annular flow, and (c) bubbly flow, courtesy of Waelchli and Rudolf von Rohr [84]

Grahic Jump Location
Fig. 5

Schematic illustration of confocal microscopy

Grahic Jump Location
Fig. 6

Particle images taken by (a) CSLM and (b) widefield fluorescent microscopy, courtesy of Park et al. [94]

Grahic Jump Location
Fig. 7

Scheme of data analysis for the determination of the film thickness: (a) optical slices in direction of the channel depth recorded with the CSLM. (b) Reconstruction of yz slices. (c) Average image of all yz slices in channel length direction. (d) Average image of the channel cross section with a schematic outline of the channel wall and observed films. Film thicknesses at the channel top (δf) and in the corner (δc) were measured, courtesy of Fries et al. [85].

Grahic Jump Location
Fig. 8

Schematic of a micro-PIV setup using a microscope, adopted from Lindken et al. [1]

Grahic Jump Location
Fig. 9

(a) Gas-liquid distribution within a ceramic monolith. (b) The map produced by correction to the image intensities arising from resonance frequency inhomogeneity and averaging the signal intensities across the width of each channel. (c) The ternary-gated map showing gas (black), solid (gray), and liquid (white), courtesy of Gladden et al. [112].



Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In