Wall shear rate in the Taylor–Couette–Poiseuille flow at low axial Reynolds number

Abstract An experimental investigation was done by the use of visual observations and the electrochemical technique in order to study the appearance of hydrodynamic instabilities at low Re axg in the gap between two coaxial cylinders, with radius ratio R r / R s =0.615 and aspect ratio L / e =24. A motor drove the inner cylinder and the outer cylinder was fixed. A Newtonian fluid (Emkarox HV45) and two non-Newtonian fluids (aqueous solutions of guar and CMC) have been used. The analysis of the evolution of the size of the Taylor vortices is carried out for Re axg Re axg Ta g ≈80, and a stretching phase for Ta g >80. For higher Re axg , the contraction phase vanished and the vortices progressively stretched with increasing Ta g . A dimensionless representation was also proposed for wall friction generalized to non-Newtonian fluids following the Ostwald law.

[1]  J. Leuliet,et al.  Modélisation de la vitesse de cisaillement apparente dans un échangeur de chaleur à surface raclée. Application aux performances thermiques avec des produits non newtoniens , 1987 .

[2]  T. Wei,et al.  Effect of polymer additives on Görtler vortices in Taylor—Couette flow , 1995, Journal of Fluid Mechanics.

[3]  K. Kataoka,et al.  Heat/mass transfer in taylor vortex flow with constant axial flow rates , 1977 .

[4]  C. Cooney,et al.  Analysis of a Taylor–Poiseuille vortex flow reactor—I: Flow patterns and mass transfer characteristics , 1998 .

[5]  Jack Legrand,et al.  Diffusion coefficients of ferricyanide ions in polymeric solutions — comparison of different experimental methods , 2000 .

[6]  V. Sobolík,et al.  Study of Taylor-Couette flow using a three-segment electrodiffusion probe , 1995 .

[7]  T. J. Hanratty.  Use of the polarographic method to measure wall shear stress , 1991 .

[8]  E. Dickinson,et al.  Food Macromolecules and Colloids , 1995 .

[9]  M. Jastrzębski,et al.  The stability of the helical flow of pseudoplastic liquids in a narrow annular gap with a rotating inner cylinder , 1990 .

[10]  J. Legrand,et al.  Structure dynamique et transfert de matiere liquide-paroi dans le cas de l’ecoulement laminaire tourbillonnaire de Couette-Poiseuille , 1983 .

[11]  O. Wein,et al.  Calibration of electrodiffusion friction probes using a voltage-step transient , 1998 .

[12]  S. Richardson,et al.  The stability of inelastic non-Newtonian fluids in Couette flow between concentric cylinders: a finite-element study , 1992 .

[13]  S. Chandrasekhar.  Hydrodynamic and Hydromagnetic Stability , 1961 .

[14]  Experimental investigations of the stability limit of the helical flow of pseudoplastic liquids , 1990 .

[15]  S. Woodruff,et al.  Görtler vortex formation at the inner cylinder in Taylor–Couette flow , 1992, Journal of Fluid Mechanics.

[16]  Thomas J. Hanratty,et al.  An experimental study of the unsteady nature of the viscous sublayer , 1963 .

[17]  S. Craig,et al.  Heat transfer to pseudoplastic fluids in laminar flow , 1962 .

[18]  R. DiPrima,et al.  The stability of a viscous fluid between rotating cylinders with an axial flow , 1960, Journal of Fluid Mechanics.

[19]  J. Legrand,et al.  Transfert de matiere global liquide-paroi pour des ecoulements associant tourbillons de taylor et circulation axiale forcee , 1982 .