Particle pressure in a sheared suspension: a bridge from osmosis to granular dilatancy.

The normal stress exerted by particles in a sheared suspension is measured by analogy with a method used to measure osmotic pressure in solutions. Particles in a liquid are confined by a fine screen to a gap between two vertical concentric cylinders, the inner of which rotates. Pressure in the liquid is sensed either by a manometer or by a pressure transducer across the screen. The particles are large enough so that Brownian motion and equilibrium osmotic pressure are vanishingly small. The measured pressure yields the shear-induced particle pressure Pi, the nonequilibrium continuation of equilibrium osmotic pressure. For volume fractions 0.3< or =varphi< or =0.5, Pi is strongly dependent on varphi, and linear in shear rate. Comparisons of the measured particle pressure with modeling and simulation show good agreement.

[1]  Osborne Reynolds Ll.D. F.R.S..  LVII. On the dilatancy of media composed of rigid particles in contact. With experimental illustrations , 1885 .

[2]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[3]  A. Einstein.  Über die von der molekularkinetischen Theorie der Wärme geforderte Bewegung von in ruhenden Flüssigkeiten suspendierten Teilchen [AdP 17, 549 (1905)] , 2005, Annalen der Physik.

[4]  Andreas Acrivos,et al.  Measurement of shear-induced self-diffusion in concentrated suspensions of spheres , 1987, Journal of Fluid Mechanics.

[5]  A. Acrivos,et al.  The shear-induced migration of particles in concentrated suspensions , 1987, Journal of Fluid Mechanics.

[6]  D. A. Saville,et al.  Colloidal Dispersions: ACKNOWLEDGEMENTS , 1989 .

[7]  David J. Jeffrey,et al.  The pressure moments for two rigid spheres in low-Reynolds-number flow , 1993 .

[8]  J. Brady,et al.  Pressure-driven flow of suspensions: simulation and theory , 1994, Journal of Fluid Mechanics.

[9]  Andreas Acrivos,et al.  Apparent wall slip velocity coefficients in concentrated suspensions of noncolloidal particles , 1995 .

[10]  John F. Brady,et al.  Normal stresses in colloidal dispersions , 1995 .

[11]  D. Prasad,et al.  Particle stress and viscous compaction during shear of dense suspensions , 1995 .

[12]  Martin,et al.  Hydrodynamic dispersion of noncolloidal suspensions: Measurement from Einstein's argument. , 1995, Physical review letters.

[13]  L. G. Leal,et al.  An experimental study of the motion of concentrated suspensions in two-dimensional channel flow. Part 1. Monodisperse systems , 1998, Journal of Fluid Mechanics.

[14]  Anubhav Tripathi,et al.  The measurement of the shear-induced particle and fluid tracer diffusivities in concentrated suspensions by a novel method , 1998, Journal of Fluid Mechanics.

[15]  Jeffrey F. Morris,et al.  Curvilinear flows of noncolloidal suspensions: The role of normal stresses , 1999 .

[16]  David T. Leighton,et al.  The characterization of the total stress of concentrated suspensions of noncolloidal spheres in Newtonian fluids , 2000 .

[17]  D. Ende,et al.  Measurement of the full shear-induced self-diffusion tensor of noncolloidal suspensions , 2002 .

[18]  John F. Brady,et al.  Rheology and microstructure in concentrated noncolloidal suspensions , 2002 .

[19]  Eric R. Weeks,et al.  Particle migration in pressure-driven flow of a Brownian suspension , 2003, Journal of Fluid Mechanics.

[20]  I. Cohen,et al.  Shear-induced configurations of confined colloidal suspensions. , 2004, Physical review letters.

[21]  J. F. Brady,et al.  Chaos and threshold for irreversibility in sheared suspensions , 2005, Nature.

[22]  Ericka Stricklin-Parker,et al.  Ann , 2005 .

[23]  Jeffrey F. Morris,et al.  Particle pressure in sheared Brownian suspensions , 2008 .