Role of micro-convection due to non-affine motion of particles in a mono-disperse suspension

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Abstract

Non-affine translation of suspended particles in a flowing suspension causes micro-convection of the fluid in the vicinity of the particle which affects the local transport mechanisms in the suspension. To investigate the importance of micro-convection on heat transport, a unit cell approach is adopted. A parametric study investigates the influence of particle fall velocity in a quiescent fluid and particle volume fraction on micro-convection in a sedimenting suspension. The thermal flux across the unit cell is shown to be a function of modified Péclet number that includes the influence of volume fraction for the range of volume fractions (0 < ε < 0.3) and for Pe ≈ O(1). This is used to investigate the influence of hindered settling on transport processes such as heat transfer occurring in a sedimenting suspension.

References (10)

  • A. Bejan

    Convection Heat Transfer

    (1984)
  • S.L. Soo

    Heat transfer due to convective interaction in fluid-solid mixtures

    ASME, 90-WAIHT-14

    (Nov. 25–30, 1990)
  • L.G. Leal

    On the effective conductivity of a dilute suspension of spherical drops in the limit of low particle Péclet number

    Chem. Eng. Commun.

    (1973)
  • C.W. Sohn et al.

    Microconvective thermal conductivity in disperse two-phase mixtures as observed in a low velocity Couette flow experiment

    J. Heat Transfer

    (1981)
  • S.K. Gupte et al.

    A cell model to investigate the influence of fall velocity distribution on transport processes in a sedimenting suspension

There are more references available in the full text version of this article.

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