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Examination of large-scale structures in turbulent microchannel flow

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Abstract

Microscopic particle image velocimetry was performed on turbulent flow in microchannels of various diameters and aspect ratios to evaluate the characteristics of large-scale turbulent structures. Spatial correlations of velocity fluctuations were measured along the channel centerlines and at four other locations, and characteristic turbulent length scales were defined. For square microchannels, excellent agreement was observed between the measured length scales and results for macro-scale duct flow. Along the centerline of the square microchannels the normalized longitudinal length scale, 2Lx uu /W, ranged from 0.30 to 0.37, the lateral length scale, 2Ly uu /W, ranged from 0.16 to 0.18, and the ratio between the two length scales, Lx uu /Ly uu ranged from 1.88 to 2.00, results which agree well with macroscale results. Results for non-square microchannels indicate that as aspect ratio increases, the ratio Lx uu /Ly uu also increases, ranging from 2.29 for an aspect ratio of 2.09 up to 3.75 for an aspect ratio of 5.68. Measurements were repeated at various distances from the side walls of the microchannels. For the square microchannels the turbulent structures are smaller near the side walls than near the center of the microchannel with 2Lx uu /W ranging from 0.30 to 0.38 along the centerline, but dropping to 0.04–0.06 at y/(W/2)=0.94. Similar results were observed for the rectangular microchannels. For the rectangular microchannels 2Lx uu /W ranged from 0.32 to 0.42, compared to 0.30–0.38 for the square microchannels.

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Abbreviations

D h :

Hydraulic diameter (μm)

L :

Turbulent length scale (μm)

M :

Magnification (-)

NA :

Numerical aperture (-)

R :

Spatial correlation

Re :

Reynolds number (-)

u :

Longitudinal velocity in microchannel (m/s)

u′:

Instantanteous fluctuation of longintudinal velocity (m/s)

v′:

Instantaneous fluctuation of transverse velocity (m/s)

H :

Microchannel depth (μm)

W :

Microchannel width (μm)

Δt :

Time period between two laser pulses (μm)

ε s :

Surface roughness (μm)

μ:

Viscosity (kg/(m s))

〈〉:

Ensemble averaging value

x :

Longitudinal direction

y :

Transverse direction

References

  • Anderson J, Chiu D, Jackman R, Chemiavskaya O, McDonald J, Wu H, Whitesides S, Whitesides G (2000) Fabrication of topologically complex three-dimensional microfluidic systems in PDMS by rapid prototyping. Anal Chem 72:3158–3164

    Article  Google Scholar 

  • Bernard-Michel B, Monavon A, Abdo D, Simon H (2002) Particle velocity fluctuations and correlation lengths in dilute sedimenting suspensions. Phy Fluids 14(7):2339–2349

    Article  Google Scholar 

  • Bourdon C, Olsen MG, Gorby A (2004) Validation of analytical solution of depth of correlation in microscopic particle image velocimetry. Meas Sci Technol 15:318–327

    Article  Google Scholar 

  • Clark W (1970) Measurement of two-point correlations in a pipe flow using laser anemometer. PhD Thesis, University of Virginia

  • Fraser R, Pack C, Santavicca D (1986) An LDV system for turbulence length scale measurements. Exp Fluids 4:150–152

    Google Scholar 

  • Gui F, Scaringe R (1995) Enhanced heat transfer in the entrance region of microchannels. In: Proceedings of the 30th intersociety energy conversion engineering conference, vol 2, pp 289–294

  • Guo Z, Li Z (2003a) Size effect on microscale single-phase flow and heat transfer. Int J Heat Mass Trans 46:149–159

    Article  MathSciNet  Google Scholar 

  • Guo Z, Li Z (2003b) Size effect on single-phase channel flow and heat trnasfer at microscale. Int J Heat Fluid Flow 24:284–298

    Article  MathSciNet  Google Scholar 

  • Hegab H, Bari A, Ameel T (2002) Friction and convection studies of r-134a in microchannels within the transition and turbulent flow regimes. Exp Heat Trans 15:245–259

    Article  Google Scholar 

  • Henning A (1998) Microfluidic MEMS. In: IEEE aerospace conference, Snowmass, Colorado, p 4.906

  • Hetsroni G, Mosyak A, Pogrebnyak E, Yarin L (2005) Fluid flow in micro-channels. Int J Heat Mass Trans 48:1982–1998

    Article  Google Scholar 

  • Jo B, Van Lerverghe L, Motsegood K, Beebe D (2000) Three-dimensional microchannel fabrication in polydimethylsiloxane (PDMS) elastomer. J Microelectromech Sys 9:76–81

    Article  Google Scholar 

  • Judy J, Maynes D, Webb B (2002) Characterization of frictional pressure drop for liquid flows through microchannels. Int J Heat Mass Trans 45:3477–3489

    Article  Google Scholar 

  • Li H, Olsen M (2006a) Aspect ratio effects on turbulent and transitional flow is rectangular microchannels as measured by microPIV. J Fluids Eng 128:305–315

    Article  Google Scholar 

  • Li H, Olsen M (2006b) MicroPIV measurements of turbulent flow in square microchannels with hydraulic diameters from 200 μm to 640 μm. Int J Heat Fluid Flow 27:123–134

    Article  Google Scholar 

  • Li H, Ewoldt R, Olsen M (2005) Turbulent and transitional velocity measurements in a rectangular microchannel using microscopic particle image velocimetry. Exp Therm Fluid Sci 29:435–446

    Article  Google Scholar 

  • Lipman J (1999) Microfluidics puts big labs on small chips. EDN Magaz pp 79–86

  • Mala G, Li D (1999) Flow characteristics of water in microtubes. International J Heat Fluid Flow 20:142–148

    Article  Google Scholar 

  • Morton J, Clark W (1971) Measurements of two-points velocity correlations in a pipe flow using laser anemometers. J Phy E Sci Instrum 4:809–814

    Article  Google Scholar 

  • Olsen M, Adrian R (2000a) Brownian motion and correlation in particle image velocimetry. Opt Laser Technol 32:621–627

    Article  Google Scholar 

  • Olsen M, Adrian R (2000b) Out-of-focus effects on particle image visibility and correlation in microscopic particle image velocimetry. Exp Fluids 29:S166–S174

    Article  Google Scholar 

  • Peng X, Peterson G (1996) Convective heat transfer and fluid flow friction for water flow in microchannel structures. Int J Heat Mass Trans 39:2599–2608

    Article  Google Scholar 

  • Peng X, Peterson G, Wang B (1994) Frictional flow characteristics of water flowing through rectangular microchannels. Exp Heat Trans, 7:249–264

    Google Scholar 

  • Pfund D, Rector D, Shekarriz A, Popescu A, Welty J (2000) Pressure drop measurements in a microchannel. Fluid Mech Transp Phenomena 46(8):1496–1507

    Google Scholar 

  • Prasad A, Adrian R, Landreth C, Offutt P (1992) Effect of resolution on the speed and accuracy of particle image velocimetry interrogation. Exp Fluids 13:105–116

    Article  Google Scholar 

  • Qu W, Mudawar I (2002) Experimental and numerical study of pressure drop and heat transfer in a single-phase micro-channel heat sink. Int J Heat Mass Trans 45:2549–2565

    Article  Google Scholar 

  • Qu W, Mala G, Li D (2000) Pressure-driven water flows in trapezoidal silicon microchannels. Int J Heat Mass Trans 43:353–364

    Article  MATH  Google Scholar 

  • Sabry M (2000) Scale effects on fluid flow and heat transfer in microchannels. IEEE Trans Components Packaging Technol 23(3):562–567

    Article  Google Scholar 

  • Santiago J, Wereley S, Meinhart C, Beebe D, Adrian R (1998) A particle image velocimetry system for microfluidics. Exp Fluids 25:316–319

    Article  Google Scholar 

  • Sharp K, Adrian R (2004) Transition from laminar to turbulent flow in liquid filled microtubes. Exp Fluids 36:741–747

    Article  Google Scholar 

  • Taylor G (1936) Correlation measurements in turbulent flow through a pipe. In: Proceedings of the Royal Society A, vol 157, pp 537–546

  • Tuckerman D, Pease R (1981) High-performance heat sinking for VLSI. IEEE Elect Dev Let 2:126–129

    Article  Google Scholar 

  • Wang Q, Squires K, Wu X (1995) Lagrangian statistics in turbulent channel flow. Atmos Environ 29:2417–2427

    Article  Google Scholar 

  • Wu H, Cheng P (2003) Friction factors in smooth trapezoidal silicon microchannels with different aspect ratios. Int J Heat Mass Trans 46:2519–2525

    Article  MathSciNet  Google Scholar 

  • Wu P, Little W (1983) Measurement of friction factor for flow of gases in very fine channels used for micro-miniature joule-thompson refrigerators. Cryogenics 23:273–277

    Article  Google Scholar 

  • Wu P, Little W (1984) Measurement of the heat transfer characteristics of gas flow in fine channel heat exchangers used for microminiature refrigerators. Cryogenics 24:415–420

    Article  Google Scholar 

Download references

Acknowledgements

The work was funded by the National Science Foundation under grant number CTS-0134469.

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Authors and Affiliations

  1. Department of Mechanical Engineering, Iowa State University, 3025 H.M. Black Engineering Building, Ames, IA, 50010, USA

    Hao Li & Michael G. Olsen

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  1. Hao Li
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  2. Michael G. Olsen
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Correspondence to Michael G. Olsen.

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Li, H., Olsen, M.G. Examination of large-scale structures in turbulent microchannel flow. Exp Fluids 40, 733–743 (2006). https://doi.org/10.1007/s00348-006-0110-4

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