Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
권호 표지
DOI QR코드

DOI QR Code

Experimental Study on the Helical Flow Field in a Concentric Annulus with Rotating Inner Cylinders

안쪽축이 회전하는 환형관내 헬리컬 유동장의 실험적 연구

  • 황영규 (성균관대학교 기계공학부) ;
  • 김영주 (성균관대학교 대학원)
  • Published : 2000.06.01
Download PDF
⟨ Previous Next ⟩

Abstract

This experimental study concerns the characteristics of a transitional flow in a concentric annulus with a diameter ratio of 0.52, whose outer cylinder is stationary and inner one rotating. The pressure drops and skin-friction coefficients have been measured for the fully developed flow of water and that of glycerine-water solution (44%) at a inner cylinder rotational speed of $0{\sim}600$ rpm, respectively. The transitional flow has been examined by the measurement of pressure drops and the visualization of flow field, to reveal the relation of the Reynolds and Rossby numbers with the skin-friction coefficients and to understand the flow instability mechanism. The present results show that the skin-friction coefficients have the significant relation with the Rossby numbers, only for laminar regime. The occurrence of transition has been checked by the gradient changes of pressure drops and skin-friction coefficients with respect to the Reynolds numbers. The increasing rate of skin-friction coefficient due to the rotation is uniform for laminar flow regime, whereas it is suddenly reduced for transitional flow regime and, then, it is gradually declined for turbulent flow regime. Consequently, the critical (axial-flow) Reynolds number decreases as the rotational speed increases. Thus, the rotation of inner cylinder promotes the early occurrence of transition due to the excitation of taylor vortices.

Keywords

References

  1. Taylor, G. I., 1923, 'Stability of a Viscous Fluid Contained Between Two Rotating Cylinders,' Phil. Trans. A, Vol. 223, pp. 289-343 https://doi.org/10.1098/rsta.1923.0008
  2. Stuart, J. T., 1958, 'On the Nonlinear Mechanics of Hydrodynamic Stability,' J Fluid Meeh., Vol. 4, pp. 1-21. https://doi.org/10.1017/S0022112058000276
  3. Diprima, R. C., 1960, 'The Stability of a Viscous Fluid Between Rotating Cylinders with an Axial Flow,' J Fluid Meeh., Vol. 366, pp. 621-631 https://doi.org/10.1017/S0022112060001365
  4. Yamada, Y., 1962, 'Resistance of a Flow through an Annulus with an Inner Rotating Cylinder,' Bull. JSME, Vol. 5, No. 18, pp. 302-310
  5. Yamada, Y., Nakabayashi, K. and Maeda, K., 1969, 'Pressure Drop of the Flow through Eccentric Cylinder with Rotating Inner Cylinders,' Bull. JSME, Vol. 12, No. 53, pp. 1032-1040
  6. Yamada, Y. and Watanabe, S., 1973, 'Frictional Moment and Pressure Drop of the Flow through Co-Axial Cylinders with an Outer Rotating Cylinder,' Bull. JSME, Vol. 16, No. 93, pp. 551 -559
  7. Nakabayashi, K., Yamada, Y. and Seo, K., 1974, 'Rotational and Axial through the Gap between Eccentric Cylinders of which the Outer One Rotates,' Bull. JSME, Vol. 17, No. 114, pp. 1564-1571
  8. Nouri, J. M., Umur, H. and Whitelaw, J. H., 1993, 'Flow of Newtonian and Non-Newtonian Fluids in Concentric and Eccentric Annuli,' J Fluid Meeh., Vol. 253, pp. 617-641 https://doi.org/10.1017/S0022112093001922
  9. 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
  10. Delwiche, R. A., Stratabit, D. B. and Lejeune, M. W. D., 1992, 'Slimhole Drilling Hydraulics,' Society of Petroleum Engineers Inc., SPE 24596 pp. 521-541
  11. Bird, R. R., Stewart, W. E. and Lightfoot, E. N., 1960, Transport Phenomena, pp. 34-70
  12. Ogawa, A., 1993, Vortex Flow, CRC Press Inc., pp. 169-192
  13. Becker, K. M. and Kaye, J., 1962, 'Measurements of Diabatic Flow in an Annulus With an Inner Rotating Cylinder,' J. Heat Transfer, Vol. 84, pp. 97-105