Fluid motion around and through a porous cylinder

Abstract The flow-field and solute transport through and around a porous cylinder is investigated numerically. The range of Reynolds number (based on the cylinder diameter and the uniform sinking rate of the cylinder) considered here is between 1 and 40 with Darcy number (Da) in the range 10 - 6 ⩽ Da ⩽ 1.5 and porosity in the range 0.629 ⩽ e ⩽ 0.999 . The motivation of the present study is the application of flow through porous cylinder extensively applied in nuclear biological chemical filters as well as reduction of carbon fines in filtered water. The influence of Da on the drag coefficient, separation angle, recirculation length, streamline and vorticity pattern are investigated. The drag ratio, defined as the ratio of drag coefficient of porous cylinder to that of solid cylinder, is found to approach zero from unity as Da is increased from 10 - 6 to 1.5 . The separation point shifts towards the rear stagnation point as Da is increased. The time evolution of the solutal field at different Reynolds number and Darcy number is presented. A long slender concentration plume is found to evolve from the cylinder with decreasing concentration at the outer edge.

[1]  Marco Vanni,et al.  Creeping flow over spherical permeable aggregates , 2000 .

[2]  S. Dennis,et al.  Numerical solutions for steady flow past a circular cylinder at Reynolds numbers up to 100 , 1970, Journal of Fluid Mechanics.

[3]  A. Bejan,et al.  Convection in Porous Media , 1992 .

[4]  B. Fornberg.  A numerical study of steady viscous flow past a circular cylinder , 1980, Journal of Fluid Mechanics.

[5]  A. Alldredge,et al.  In situ settling behavior of marine snow1 , 1988 .

[6]  L. Mathelin,et al.  The Effect of Uniform Blowing on the Flow Past a Circular Cylinder , 2002 .

[7]  J. Masliyah,et al.  Laminar flow past a permeable sphere , 1982 .

[8]  K. N. Seetharamu,et al.  Natural convective heat transfer in a fluid saturated variable porosity medium , 1997 .

[9]  Creeping flow past and within a permeable spheroid , 2002 .

[10]  A. Alldredge,et al.  Direct observations of the mass flocculation of diatom blooms: characteristics, settling velocities and formation of diatom aggregates , 1989 .

[11]  A. Munitsyn.  Three-dimensional non-linear oscillations of a rod with hinged supports , 2006 .

[12]  U. H. Thygesen,et al.  Fluid motion and solute distribution around sinking aggregates. I. Small-scale fluxes and heterogeneity of nutrients in the pelagic environment , 2001 .

[13]  K. Vafai,et al.  Forced Convection in a Channel Filled With a Porous Medium: An Exact Solution , 1989 .

[14]  H. Brauer,et al.  Fluiddynamik bei quer angeströmten Zylindern , 1975 .

[15]  H. Jiménez-Islas,et al.  Natural convection in a cylindrical porous cavity with internal heat source: a numerical study with Brinkman-extended Darcy model , 1999 .

[16]  Mobility of permeable aggregates: effects of shape and porosity , 2004 .

[17]  L. Wolfersdorf.  Potential Flow Past a Circular Cylinder with Permeable Surface , 1988 .

[18]  Pierre M. Adler,et al.  Porous media : geometry and transports , 1992 .

[19]  J. Masliyah,et al.  Terminal velocity of porous spheres , 1980 .

[20]  A. Basu,et al.  Computation of flow through a fluid-sediment interface in a benthic chamber , 1999 .

[21]  M. Braza,et al.  Numerical study and physical analysis of the pressure and velocity fields in the near wake of a circular cylinder , 1986, Journal of Fluid Mechanics.

[22]  S. Patankar.  Numerical Heat Transfer and Fluid Flow , 2018, Lecture Notes in Mechanical Engineering.

[23]  U. H. Thygesen,et al.  Fluid motion and solute distribution around sinking aggregates. II. Implications for remote detection by colonizing zooplankters , 2001 .

[24]  L. Glicksman,et al.  Drag on a permeable cylinder in steady flow at moderate Reynolds numbers , 1998 .