A Numerical Study on the Eccentric Rotation Flow Characteristics of Drilling Fluid in Annuli

환형관내 굴착유체의 편심회전유동에 관한 수치해석적 연구

  • 서병택 (용인송담대학 건축소방설비과) ;
  • 장영근 (용인송담대학 건축소방설비과) ;
  • 김덕주 (용인송담대학 건축소방설비과)
  • Received : 2011.11.17
  • Accepted : 2011.12.21
  • Published : 2011.12.31

Abstract

The paper concerns numerical study of fully developed laminar flow of a Newtonian water and non-Newtonian fluids, 0.2% aqueous of sodium carboxymethyl cellulose(CMC) solution in eccentric annuli with combined bulk axial flow and inner cylinder rotation. Pressure losses and skin friction coefficients have been measured when the inner cylinder rotates at the speed of 0~200 rpm. A numerical analysis considered mainly the effects of annular eccentricity and inner cylinder rotation. The present analysis has demonstrated the importance of the drill pipe rotation and eccentricity. In eccentricity of 0.7 of a Newtonian water, the flow field is recirculation dominated and unexpected behavior is observed. it generates a strong rotation directed layer, that two opposing effects act to create two local peaks of the axial velocity. The influences of rotation, radius ratio and working fluid on the annular flow field are investigated.

Keywords

References

  1. Taylor, G. I., 1923, Stability of a Viscous Fluid Contained Between Two Rotating Cylinder, Phil. Trans., A. Vol. 223, pp. 289-343. https://doi.org/10.1098/rsta.1923.0008
  2. Nouri, J. M. and Whitelaw, J. H., 1994, Flow of Newtonian and Non-Newtonian Fluids in a Concentric Annulus With Rotation of the Inner Cylinder, J. Fluids Eng., Vol. 116, pp. 821-827. https://doi.org/10.1115/1.2911856
  3. Escudier, M. P. and Gouldson, I. W., 1995, Concentric annular flow with centerbody rotation of a Newtonian and a shear-thinning liquid, Int. J. Heat and Fluid Flow., Vol. 16, pp. 156-162. https://doi.org/10.1016/0142-727X(95)00012-F
  4. Richard, E. W. and Othmen Al-Rawi, 1970, Helical Flow of Bentonite Slurries, SPE 3108.
  5. Hwang, Y. K. and Kim, Y. J., 2002, Helical flow Study on Non-Newtonian Fluid in an Inclined Annulus with Rotating Inner Cylinder, Proc. of the KSME. pp. 1944-1949.
  6. Pinho, F. T. and Whitelaw, J. H., 1990, "Flow of Non-Newtonian Fluids in A Pipes", J of Non-Newtonian Fluids Vol. 34, pp.129-144 https://doi.org/10.1016/0377-0257(90)80015-R