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Experimental study of negatively buoyant finite-size particles in a turbulent boundary layer up to dense regimes

Published online by Cambridge University Press:  13 March 2019

Lucia J. Baker*
Affiliation:
Department of Aerospace Engineering and Mechanics, University of Minnesota, Minneapolis, MN 55455, USA St. Anthony Falls Laboratory, University of Minnesota, Minneapolis, MN 55414, USA
Filippo Coletti
Affiliation:
Department of Aerospace Engineering and Mechanics, University of Minnesota, Minneapolis, MN 55455, USA St. Anthony Falls Laboratory, University of Minnesota, Minneapolis, MN 55414, USA
*
Email address for correspondence: [email protected]

Abstract

We experimentally investigate the two-phase interplay in an open-channel turbulent boundary layer laden with finite-size particles at global volume fractions between 4 and 25 %. The working fluid (water) and the dispersed phase (hydrogel spheres) have closely matched refractive indices, allowing us to measure the properties of both phases using particle image velocimetry and particle tracking velocimetry, respectively. The particles have a diameter of approximately 9 % of the channel depth and are slightly denser than the fluid. The negative buoyancy causes a strong vertical concentration gradient, characterized by discrete and closely spaced particle layers parallel to the wall. Even at the lowest considered volume fractions, the near-wall fluid velocity and velocity gradients are strongly reduced, with large mean shear throughout most of the channel height. This indicates that the local effective viscosity of the suspension is greatly increased due to the friction between particle layers sliding over one another. The particles consistently lag the fluid and leave their footprint on its mean and fluctuating velocity profiles. The turbulent activity is damped near the wall, where the nearly packed particles disrupt and suppress large-scale turbulent fluctuations and redistribute some of the kinetic energy to smaller scales. On the other hand, in the outer region of the flow where the local particle concentration is low, the mean shear produces strong Reynolds stresses, with enhanced sweeps and ejections and frequent swirling events.

Type
JFM Papers
Copyright
© 2019 Cambridge University Press 

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References

Adhikari, D.2013 Volumetric velocity measurement of aquatic predator–prey interactions. PhD thesis, University of Minnesota.Google Scholar
Bagnold, R. A. 1954 Experiments on a gravity-free dispersion of large solid spheres in a Newtonian fluid under shear. Proc. R. Soc. Lond. A 225 (1160), 4963.Google Scholar
Balachandar, S. & Eaton, J. K. 2010 Turbulent dispersed multiphase flow. Annu. Rev. Fluid Mech. 42, 111133.Google Scholar
Batchelor, G. K. & Green, J. T. 1972 The determination of the bulk stress in a suspension of spherical particles to order c 2 . J. Fluid Mech. 56 (3), 401427.Google Scholar
Bellani, G., Byron, M. L., Collignon, A. G., Meyer, C. R. & Variano, E. A. 2012 Shape effects on turbulent modulation by large nearly neutrally buoyant particles. J. Fluid Mech. 712, 4160.Google Scholar
Byron, M. L. & Variano, E. A. 2013 Refractive-index-matched hydrogel materials for measuring flow–structure interactions. Exp. Fluids 54 (2), 1456.Google Scholar
Cisse, M., Saw, E.-W., Gibert, M., Bodenschatz, E. & Bec, J. 2015 Turbulence attenuation by large neutrally buoyant particles. Phys. Fluids 27 (6), 061702.Google Scholar
Costa, P., Picano, F., Brandt, L. & Breugem, W.-P. 2016 Universal scaling laws for dense particle suspensions in turbulent wall-bounded flows. Phys. Rev. Lett. 117 (13), 134501.Google Scholar
Costa, P., Picano, F., Brandt, L. & Breugem, W.-P. 2018 Effects of the finite particle size in turbulent wall-bounded flows of dense suspensions. J. Fluid Mech. 843, 450478.Google Scholar
Crowe, C. T., Schwarzkopf, J. D., Sommerfeld, M. & Tsuji, Y. 2011 Multiphase Flows with Droplets and Particles. CRC Press.Google Scholar
Cuccia, N. L.2017 The tribological properties of polyacrylamide hydrogel particles. Honours thesis, Emory University, https://etd.library.emory.edu/concern/etds/j3860778r?locale=en.Google Scholar
Da Cruz, F., Emam, S., Prochnow, M., Roux, J.-N. & Chevoir, F. 2005 Rheophysics of dense granular materials: discrete simulation of plane shear flows. Phys. Rev. E 72 (2), 021309.Google Scholar
De Graaff, D. B. & Eaton, J. K. 2000 Reynolds-number scaling of the flat-plate turbulent boundary layer. J. Fluid Mech. 422, 319346.Google Scholar
Eilers, H. 1941 The viscosity of the emulsion of highly viscous substances as function of concentration. Kolloid-Zeitschrift 97 (3), 313321.Google Scholar
Einstein, A. 1906 Eine neue Bestimmung der Moleküldimensionen. Ann. Phys. 324 (2), 289306.Google Scholar
Elghobashi, S. 1994 On predicting particle-laden turbulent flows. Appl. Sci. Res. 52 (4), 309329.Google Scholar
Forterre, Y. & Pouliquen, O. 2008 Flows of dense granular media. Annu. Rev. Fluid Mech. 40, 124.Google Scholar
Gondret, P., Lance, M. & Petit, L. 2002 Bouncing motion of spherical particles in fluids. Phys. Fluids 14 (2), 643652.Google Scholar
Gore, R. A. & Crowe, C. T. 1991 Modulation of turbulence by a dispersed phase. Trans. ASME J. Fluids Engng 113 (2), 304307.Google Scholar
Hetsroni, G. 1989 Particles–turbulence interaction. Intl J. Multiphase Flow 15 (5), 735746.Google Scholar
Hsu, T.-J., Jenkins, J. T. & Liu, P. L.-F. 2004 On two-phase sediment transport: sheet flow of massive particles. Proc. R. Soc. Lond. A 460 (2048), 22232250.Google Scholar
Joseph, G. G., Zenit, R., Hunt, M. L. & Rosenwinkel, A. M. 2001 Particle–wall collisions in a viscous fluid. J. Fluid Mech. 433, 329346.Google Scholar
Krieger, I. M. & Dougherty, T. J. 1959 Concentration dependence of the viscosity of suspensions. Trans. Soc. Rheol. 3 (1), 137152.Google Scholar
Lashgari, I., Picano, F., Breugem, W.-P. & Brandt, L. 2014 Laminar, turbulent, and inertial shear-thickening regimes in channel flow of neutrally buoyant particle suspensions. Phys. Rev. Lett. 113 (25), 254502.Google Scholar
Loisel, V., Abbas, M., Masbernat, O. & Climent, É. 2013 The effect of neutrally buoyant finite-size particles on channel flows in the laminar-turbulent transition regime. Phys. Fluids 25 (12), 123304.Google Scholar
Lu, W.-M., Tung, K.-L., Hung, S.-M., Shiau, J.-S. & Hwang, K.-J. 2001 Compression of deformable gel particles. Powder Technol. 116 (1), 112.Google Scholar
Matas, J.-P., Morris, J. F. & Guazzelli, E. 2003 Transition to turbulence in particulate pipe flow. Phys. Rev. Lett. 90 (1), 014501.Google Scholar
Pan, Y. & Banerjee, S. 1996 Numerical simulation of particle interactions with wall turbulence. Phys. Fluids 8 (10), 27332755.Google Scholar
Picano, F., Breugem, W.-P. & Brandt, L. 2015 Turbulent channel flow of dense suspensions of neutrally buoyant spheres. J. Fluid Mech. 764, 463487.Google Scholar
Picano, F., Breugem, W.-P., Mitra, D. & Brandt, L. 2013 Shear thickening in non-Brownian suspensions: an excluded volume effect. Phys. Rev. Lett. 111 (9), 098302.Google Scholar
Pope, S. B. 2000 Turbulent Flows. Cambridge University Press.Google Scholar
Revil-Baudard, T., Chauchat, J., Hurther, D. & Barraud, P.-A. 2015 Investigation of sheet-flow processes based on novel acoustic high-resolution velocity and concentration measurements. J. Fluid Mech. 767, 130.Google Scholar
Robinson, S. K. 1991 Coherent motions in the turbulent boundary layer. Annu. Rev. Fluid Mech. 23 (1), 601639.Google Scholar
Shao, X., Wu, T. & Yu, Z. 2012 Fully resolved numerical simulation of particle-laden turbulent flow in a horizontal channel at a low Reynolds number. J. Fluid Mech. 693, 319344.Google Scholar
Sierou, A. & Brady, J. F. 2002 Rheology and microstructure in concentrated noncolloidal suspensions. J. Rheol. 46 (5), 10311056.Google Scholar
Stickel, J. J. & Powell, R. L. 2005 Fluid mechanics and rheology of dense suspensions. Annu. Rev. Fluid Mech. 37, 129149.Google Scholar
Tachie, M. F., Bergstrom, D. J. & Balachandar, R. 2003 Roughness effects in low-Re 𝜃 open-channel turbulent boundary layers. Exp. Fluids 35 (4), 338346.Google Scholar
Underwood, E. E. 1969 Stereology, or the quantitative evaluation of microstructures. J. Microsc. 89 (2), 161180.Google Scholar
Wang, G., Abbas, M. & Climent, É. 2017 Modulation of large-scale structures by neutrally buoyant and inertial finite-size particles in turbulent Couette flow. Phys. Rev. Fluids 2 (8), 084302.Google Scholar
Wang, G., Abbas, M. & Climent, E. 2018 Modulation of the regeneration cycle by neutrally buoyant finite-size particles. J. Fluid Mech. 852, 257282.Google Scholar
Westerweel, J. & Scarano, F. 2005 Universal outlier detection for PIV data. Exp. Fluids 39 (6), 10961100.Google Scholar
Yeo, K., Dong, S., Climent, É. & Maxey, M. R. 2010 Modulation of homogeneous turbulence seeded with finite size bubbles or particles. Intl J. Multiphase Flow 36 (3), 221233.Google Scholar
Yeo, K. & Maxey, M. R. 2010 Dynamics of concentrated suspensions of non-colloidal particles in Couette flow. J. Fluid Mech. 649, 205231.Google Scholar
Zade, S., Costa, P., Fornari, W., Lundell, F. & Brandt, L. 2018 Experimental investigation of turbulent suspensions of spherical particles in a square duct. J. Fluid Mech. 857, 748783.Google Scholar
Zhang, K. & Rival, D. E. 2018 Experimental study of turbulence decay in dense suspensions using index-matched hydrogel particles. Phys. Fluids 30 (7), 073301.Google Scholar
Zhang, Q. & Prosperetti, A. 2010 Physics-based analysis of the hydrodynamic stress in a fluid-particle system. Phys. Fluids 22 (3), 033306.Google Scholar
Zhou, J., Adrian, R. J., Balachandar, S. & Kendall, T. M. 1999 Mechanisms for generating coherent packets of hairpin vortices in channel flow. J. Fluid Mech. 387, 353396.Google Scholar