International Journal of Air-Conditioning and Refrigeration

  • 제10권1호
  • /
  • Pages.10-18
  • /
  • 2002
  • /
  • 2010-1325(pISSN)
  • /
  • 2010-1333(eISSN)
대한설비공학회 (The Society of Air-Conditioning and Refrigerating Engineers of Korea)
권호 표지

Thermal Analysis on Triple-Passage Heat Exchangers for a Continuous Hot-Steel Tube Cooling System

  • Ko, Bong-Hwan (Graduate School,Department of Mechanical and System Design Engineering, Hongik University) ;
  • Park, Seung-Ho (Department of Mechanical and System Design Engineering, Hongik University)
  • 발행 : 2002.03.01
PDF 다운로드
⟨ 이전 논문 다음 논문 ⟩

초록

The objective of present study is to analyze a concentric triple-passage heat exchanger for an optimal design of a continuous hot steel-tube cooling system, where a hot-steel tube line is passing through an antioxidant gas with a constant speed. Velocities and temperatures of the inert gas flowing between inner and outer tubes are calculated theoretically for laminar and numerically for turbulent flow regimes. From their profiles Nusselt numbers and friction factors are calculated (or various ratios of inner/outer tube radii and relative velocities. With these Nusselt numbers triple-passage heat exchangers are investigated for their thermal characteristics. It is shown that heat transfer coefficients based on ratios of average heat fluxes from inner and outer tubes might result in great errors for the temperature distributions of the flows, since local heat transfer coefficients for flows through an annulus are dependent on local wall heat flux ratios.

키워드

참고문헌

  1. Agency for Technology and Standards, 1979, Metal Tubes and Tubing for Automobiles, KS R 2028, Korean Standards Association
  2. Sekulic, D. P. and Shah, R. K., 1995, Thermal design theory of three-fluid heat exchangers, Advances In Heat Transfer, Vol. 26, pp. 219-328
  3. Tsuchiya, K., Ohuchi, N., Terashima, A. and Shinkai, K., 1990, Cryogenic system of the superconducting insertion quadruple magnets for tristan main ring, Advances in Cryogenic Engineering, Vol. 35, Part B, pp. 941-948
  4. Asakura, H., Kato, D., Saji, N. and Ohya, H., 1992, 80 K centrifugal compressor for helium refrigeration system, Advances in Cryogenic Engineering, Vol. 37, Part B, pp. 787-794
  5. Yanagi, H., Yaguchi, H., Yabana, T., Fujirma, K., Ino, N. and Yasuda, A., 1992, The planning of a low temperature purifier for super-GM helium refrigeration plant, Advances in Cryogenic Engineering, Vol. 37, Part A, pp. 739-746
  6. Brindza, P., Chronis, W., Rode, C., Kelley, J. P. and Shea, M., 1988, Cebaf's cryogenic system, Advances in Cryogenic Engineering, Vol. 33, pp. 623-630
  7. Yamamoto, J., Mito, T., Motojima, O., Asami, T., Ebisu, H. and Otani, T., Feasibility study of cooling system of new superconduction large helical fusion reactor, Advances in Cryogenic Engineering, Vol. 35, Part B, pp. 967-974
  8. Kays, W. M. and London, A. L., 1984, Compact Heat Exchangers, McGraw Hill
  9. Kays, W. M. and Crawford, M. E., 1993, Convective Heat and Mass Transfer, McGraw Hill, pp. 121-124
  10. Rohsenow, W. M. and Hartnett, J. P., 1973, Handbook of Heat Transfer, McGraw Hill
  11. Star-CD version 3.0 Manual, 1996, Computationa Dynamics Limited