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Effects of cross-sectional aspect ratio of V-shaped ribs and blockage ratio on heat transfer in a channel at a low Reynolds number

Abstract

V-shaped ribs were investigated with the objective of enhancing heat transfer at the high-temperature side of a fin-plate type heat exchanger used in a railway vehicle compressor. The high-temperature side supplied with compressed air has a Reynolds number of approximately 4000, which is not sufficiently high to generate strong turbulence. When a 3D printer is used to fabricate a heat exchanger, the cross-sectional aspect ratio or blockage ratio of the ribs should be greater than the optimum value in order to attain a certain value of strength. In this study, a series of numerical analyses were conducted to investigate whether increasing the aspect ratio or the blockage ratio was more advantageous for achieving high heat transfer. Ribs with cross-sectional aspect ratios ranging from 0.3 to 5 were investigated. The investigated blocking ratios were 0.1 and 0.3. The results of computational fluid dynamics calculations were used to investigate the influences of flow separation–reattachment, secondary flow, and turbulence on heat transfer. The results demonstrated that the introduction of V-shaped ribs with a high blockage ratio into the channel at a low Reynolds number resulted in greater heat transfer enhancement compared with the effect of introducing ribs with a high cross-sectional aspect ratio.

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References

  1. M. Norfolk and H. Johnson, Solid–state additive manufacturing for heat exchangers, J. Minerals, Metals and Material Society, 67 (2015) 655–659.

    Article  Google Scholar 

  2. ALMIiG, ALMIiG WP2N8ST TAO compressor user manual (2014) 32–41.

  3. J. Ahn, M. S. Kim and S. Jang, Heat transfer analysis of a heat exchanger for an air–compressor of a railway vehicle based on cooling air flow measurement, Korean J. Air–Cond. Refrig., 29 (2017) 447–454.

    Google Scholar 

  4. P. M. Ligrani, Heat transfer augmentation technologies for internal cooling of turbine components of gas turbine engine, Int. J. Rotating Machinery (2013) 275653.

    Google Scholar 

  5. J.–C. Han and S. Dutta, Recent developments in turbine blade internal cooling, Annals, 934 (2001) 179–193.

    Google Scholar 

  6. M. K. Chyu and S. C. Siw, Recent advances of internal cooling techniques for gas turbine airfoils, ASME J. Ther. Sci. Eng. Appl., 5 (2013) 021008.

    Article  Google Scholar 

  7. Y. O. Lee, J. Ahn and J. S. Lee, Effects of dimple arrangements on the turbulent heat transfer in a dimpled channel, Int. J. Enhanced Heat Transf., 19 (2012) 359–367.

    Article  Google Scholar 

  8. C.–O. Olsson and B. Sunden, Heat transfer and pressure drop characteristics of ten radiator tubes, Int. J. Heat Mass Transf., 39 (1996) 3211–3220.

    Article  Google Scholar 

  9. C.–O. Olsson and B. Sunden, Experimental study of flow and heat transfer in rib–roughened rectangular channels, Exp. Therm. Fluid Sci., 16 (1998) 349–365.

    Article  Google Scholar 

  10. S. Acharya, T. A. Myrum, X. Qiu and S. Sinha, Developing and periodically developed flow, temperature and heat transfer in a ribbed duct, Int. J. Heat Mass Transf., 40 (1997) 461–479.

    Article  Google Scholar 

  11. J. Ahn, H. Choi and J. S. Lee, Large eddy simulation of flow and heat transfer in a rotating ribbed channel, Int. J. Heat Mass Transf., 50 (2007) 4937–4947.

    Article  MATH  Google Scholar 

  12. J. Park, P. R. Desam and P. M. Ligrani, Numerical prediction of flow structure above dimpled surface in a channel, Num. Heat Transf., 45 (2004) 1–20.

    Article  Google Scholar 

  13. H. Iacovides and B. E. Launder, Computational fluid dynamics applied to internal gas–turbine blade cooling: A review, Int. J. Heat Fluid Flow (1995) 16 454–470.

    Google Scholar 

  14. D. H. Lee, D. H. Rhee, K. M. Kim, H. H. Cho and H. K. Moon, Detailed measurement of heat/mass transfer with continuous and multiple V–shaped ribs in rectangular channel, Energy, 24 (2009) 1770–1778.

    Article  Google Scholar 

  15. Q.–Y. Zhao, H. Chung, E. Y. Jung and H. H. Cho, Effects of various rib arrangements on heat transfer in a semicylinder channel with effusion flow, Num. Heat Transf. A, 61 (2017) 547–559.

    Article  Google Scholar 

  16. G. Iaccarino, A. Ooi, P. A. Durbin and M. Behina, Conjugate heat transfer predictions in two–dimensional ribbed passage, Int. J. Heat Fluid Flow, 23 (2002) 340–345.

    Article  Google Scholar 

  17. A. Murata and S. Mochizuki, Large eddy simulation with a dynamic subgrid–scale model of turbulent heat transfer in an orthogonally rotating rectangular duct with transverse rib turbulators, Int. J. Heat Mass Transf., 43 (2000) 1243–1259.

    Article  MATH  Google Scholar 

  18. J. Ahn, H. Choi and J. S. Lee, Large eddy simulation of flow and heat transfer in a channel roughened by square or semicircle ribs, ASME J. Turbomachinery, 127 (2005) 263–269.

    Article  Google Scholar 

  19. L. Casarsa and T. Arts, Experimental investigation of the aerothermal performance of a high blockage rib–roughened cooling channel, ASME J. Turbomachinery, 127 (2005) 580–588.

    Article  Google Scholar 

  20. M. E. Taslim and C. M. Wadsworth, An experimental investigation of the rib surface–averaged heat transfer coefficient in a rib–roughened square passage, ASME J. Turbomachinery, 119 (1997) 381–389.

    Article  Google Scholar 

  21. D. L. Gee and R. L Webb, Forced convection heat transfer in helically rib–roughened tubes, Int. J. Heat Mass Transf., 23 (1980) 1127–1136.

    Article  Google Scholar 

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Correspondence to Joon Ahn.

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Recommended by Associate Editor Chang Yong Park

Joon Ahn received his B.S. (1997), M.S. (1999), and Ph.D. (2003) degrees from Seoul National University, Korea. He worked as a Senior Researcher at KIER (2006−2010) and is now a Professor at Kookmin University. His research interests include heat transfer and combustion problems in energy systems.

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Ahn, J., Kim, M.S. & Jang, S. Effects of cross-sectional aspect ratio of V-shaped ribs and blockage ratio on heat transfer in a channel at a low Reynolds number. J Mech Sci Technol 32, 5465–5473 (2018). https://doi.org/10.1007/s12206-018-1044-5

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  • DOI: https://doi.org/10.1007/s12206-018-1044-5

Keywords

  • Blockage ratio
  • Cross-sectional aspect ratio
  • Heat exchanger
  • V-shaped rib