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

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

DOI QR Code

Direct Numerical Simulation of Turbulent Mixed Convection in Heated Vertical Annulus

수직 동심 환형관 내의 난류혼합대류 현상에 관한 직접수치모사

  • Published : 2009.09.01
Download PDF
⟨ Previous Next ⟩

Abstract

Turbulent mixed convection in heated vertical annulus is investigated using Direct Numerical Simulation (DNS) technique. The objective of this study is to find out the effect of buoyancy on turbulent mixed convection in heated vertical annulus. Downward and upward flows with bulk Reynolds number 8500, based on hydraulic diameter and mean velocity, have been simulated to investigate turbulent mixed convection by gradually increasing the effect of buoyancy. With increased heat flux, heat transfer coefficient first decreases and then increases in the upward flow due to the effect of buoyancy, but it gradually increases in downward flow. The mean velocity and temperature profiles can not be explained by the wall log laws due to the effect of buoyancy, too. All simulation results are in good quantitative agreement with existing numerical results and in good qualitative agreement with existing experimental results.

Keywords

References

  1. Yoo, J. W., Yoo, J. Y. and Choi, H. C., 2003, 'Direct Numerical Simulation of Heated Vertical Air Flows in Fully Developed Turbulent Mixed Convection,' Int. J. Heat Mass Transfer, Vol. 46, No. 9, pp. 1613-1627 https://doi.org/10.1016/S0017-9310(02)00442-8
  2. Jackson, J. D., Cotton, M. A., Axcell, B. P., 1989, 'Studies of Mixed Convection in Vertical Tubes,' Int. J. Heat Fluid Flow, Vol. 10, No. 1, pp. 2-15 https://doi.org/10.1016/0142-727X(89)90049-0
  3. Parlatan, Y., Todreas, N. E. and Driscoll, M. J., 1996, 'Buoyancy and Property Variation Effects in Turbulent Mixed Convection of Water in Vertical Tubes,' J. Heat Transfer, Vol. 118, No. 2, pp. 381-387 https://doi.org/10.1115/1.2825855
  4. Nouri, J. M., Umur, H. and Whitelaw, J. H., 1993, 'Flow of Newtonian and Non-Newtonian Fluids in Concentric and Eccentric Annuli,' J. of Fluid Mech., Vol. 253, pp. 617-641 https://doi.org/10.1017/S0022112093001922
  5. Escudier, M. P., Gouldson, I. W. and Jones, D. M., 1995, 'Flow of Shear-thinning Fluids in a Concentric Annulus,' Exp. in Fluids, Vol. 18, pp. 225-238 https://doi.org/10.1007/BF00195092
  6. Chung, S. Y., Rhee, G. H. and Sung, H. J., 2002, 'Direct Numerical Simulation Of Turbulent Concentric Annular Pipe Flow. Part 1: Flow Field,' Int. J. Heat Fluid Flow, Vol. 23, pp. 426-440 https://doi.org/10.1016/S0142-727X(02)00140-6
  7. Xu, Z., 2002, 'Study of the Influences of Buoyancy on Turbulent Flow and Heat Transfer in a Vertical Passage of Annular Cross-section,' Ph. D. Thesis, University of Manchester
  8. Kang, S., Patil, B., Zarate, J. A. and Roy, R. P., 2001, 'Isothermal and Heated Turbulent Upflow in a Vertical Annular Channel - Part I. Experimental Measurements,' Int. J. Heat Mass Transfer, Vol. 44, pp. 1171-1184 https://doi.org/10.1016/S0017-9310(00)00150-2
  9. Zarate, J. A., Roy, R. P. and Laporta, A., 2001, 'Isothermal and Heated Turbulent Upflow in a Vertical Annular Channel - Part II. Numerical Simulations,' Int. J. Heat Mass Transfer, Vol. 44, pp. 1185-1199 https://doi.org/10.1016/S0017-9310(00)00151-4
  10. Akselvoll, K. and Moin, P., 1995, 'Large Eddy Simulation of Turbulent Confined Coannular Jets and Turbulent Flow Over a Backward Facing Step,' Mech. Eng. Dept. Report TF-63, Stanford University
  11. Buchhave, P., George, W. K. and Lumley, J. L., 1979, 'The Measurement of Turbulence with the Laser-Doppler Anemometer,' Annual Review of Fluid Mechanics, Vol. 11, pp. 443-503 https://doi.org/10.1146/annurev.fl.11.010179.002303
  12. Shen, Y., Xia, K. Q. and Tong, P., 1995, 'Measured Local-Velocity Fluctuations in Turbulent Convection,' Phys. Rev. Lett., Vol. 75, No. 3, pp. 437-440 https://doi.org/10.1103/PhysRevLett.75.437
  13. van Maanen, H. R. E., 1999, 'Retrieval of Turbulence and Turbulence Properties from Randomly Sampled Laser-Doppler Anemometry Data with Noise,' Ph. D. Thesis, Technische Universiteit Delft