International Scientific Journal


The flow boiling heat transfer study of R-134a/R-290/R-600a refrigerant mixture is carried out in a vertical helical evaporator test section. The test section is immersed in an agitated ethylene glycol-water bath maintained at constant temperature. An aluminum test section with a height of 0.22 m, tube inside diameter of 6.35 mm, outside diameter of 8 mm and coil length of 8 m is used. The influences of various operating parameters such as evaporating temperature, bath temperature, and refrigerant composition on the heat transfer coefficient are investigated experimentally. Using the same experimental results the shell side flow boiling heat transfer coefficient correlation in helical evaporator is also evolved.
PAPER REVISED: 2009-04-21
PAPER ACCEPTED: 2009-04-21
CITATION EXPORT: view in browser or download as text file
  1. ***, United Nations Environment Programme, Montreal Protocol on Substances that Deplete the Ozone Layer-Final Act, 1989
  2. Spauschus, H. O., HFC 134a as a Substitute Refrigerant for CFC 12, Int. J. Refrigeration, 11 (1988), 6, pp. 389-392
  3. Jung, D. S., Radermacher, R., Performance Simulation of Single-Evaporator Domestic Refrigerators Charged with Pure and Mixed Refrigerants, Int J. Refrigeration, 14 (1991), 4, pp. 223-232
  4. Carpenter, N. E., Retrofitting HFC 134a into Existing CFC 12 Systems, Int J. Refrigeration, 15 (1992), 6, pp. 332-348
  5. Devotta, S., Gopichand, S., Comparative Assessment of HFC134a and Some Refrigerants as Alternatives to CFC12, Int. J. Refrigeration, 15 (2) (1992), 2, pp. 112-118
  6. Jung, D., et al., Testing of a Hydrocarbon Mixture in Domestic Refrigerators, ASHRAE Trans., 19 (1996), 3, pp. 1077-1084
  7. Granryd, E., Hydrocarbons as Refrigerants - An Overview, Int. J. Refrigeration, 24 (2001), 1, pp.15-24
  8. Fatouh, M., El Kafafy, M., Assessment of Propane/Commercial Butane Mixtures as Possible Alternatives to R134a in Domestic Refrigerators, Energy Conversion and Management, 47 (2006), 15, pp. 2644-2658
  9. Janssen, M., Engels, F., The Use of HFC134a with Mineral Oil in Hermetic Cooling Equipment, Report 95403/NO 07, International Congress of Refrigeration, The Hague, 1995
  10. Sekhar, S. J., Lal, D. M., Renganarayanan, S., Improved Energy Efficiency for CFC Domestic Refrigerators Retrofitted with Ozone-Friendly HFC134a/HC Refrigerant Mixture, Int. J. Thermal Sciences, 43 (2004), 3, pp. 307-314
  11. Sekhar, S. J., Kumar, K. S., Lal, D. M., Ozone Friendly HFC134a/HC Mixture Compatible with Mineral Oil in Refrigeration System Improves Energy Efficiency of a Walk in Cooler, Energy Conversion and Management, 45 (2004), 3, pp.1175-1186
  12. Raja, B., Lal, D. M., Saravanan, R., Flow Boiling Heat Transfer Coefficient of R-134a/R-290/R-600a Mixture in a Smooth Horizontal Tube, Thermal Science, 12 (2008), 3, pp. 33-44
  13. Jung, D. S., et al., A Study of Flow Boiling Heat Transfer with Refrigerant Mixtures, Int. J. of Heat and Mass Transfer, 32 (1989), 9, pp. 1751-1764
  14. Shin, J. Y., Kim, M. S., Ro, S. T., Experimental Study on Forced Convective Boiling Heat Transfer of Pure Refrigerants and Refrigerant Mixtures in a Horizontal Tube, Int. J. Refrigeration, 20 (1997), 4, pp. 267-275
  15. Wattelet, J. P., et al., Evaporative Characteristics of R12, R134a and a Mixture at Low Mass Fluxes, ASHRAE Trans. Symposia, 2 (1994), 1, pp. 603-615
  16. Aprea, C., Rossi, F., Greco, A., Experimental Evaluation of R22 and R407C Evaporative Heat Transfer Coefficient in a Vapour Compression Plant, Int. J. Refrigeration, 23 (2000), 5, pp. 366-377
  17. Jabardo, J. M. S., Filho, E. P. B., Convective Boiling of Halocarbon Refrigerants Flowing in a Horizontal Copper Tube - an Experimental Study, Experimental Thermal and Fluid Science, 23 (2000), 13, pp. 93-104
  18. Ali, M. E., Experimental Investigation of Natural Convection from Vertical Helical Coiled Tubes, Int. J. Heat Mass Transfer, 37 (1994), 4, pp. 665-671
  19. Rogers, G. F. C, Mayhew, Y. R, Heat Transfer and Pressure Loss in Helically Coiled Tubes with Turbulent Flow, Int. J. Heat Mass Trans, 7 (1964), 11, pp. 1207-1216
  20. Prabanjan, D. G., Rennie, T. J., Raghavan, G. S. V., Natural Convection Heat Transfer from Helical Coiled Tubes, Int. J. of Thermal Sciences, 43 (2004), 4, pp. 359-365
  21. Ali, M. E., Free Convection Heat Transfer from the Outer Surface of Vertically Oriented Helical Coils in Glycerol-Water Solution, Heat and Mass Transfer, 40 (2004), 8, pp. 615-620
  22. Jeong, S., Jeong, D., Lee, J. J., Evaporating Heat Transfer and Pressure Drop Inside Helical Coils with the Refrigerant Carbon Dioxide, Proceedings, 21st International Congress on Refrigeration, Washington D. C., 2003, pp. 1-6
  23. Unal, H. C., Van Gasself, M. L. G., Versalt, P. M., Dryout and Two-Phase Flow Pressure Drop in Sodium Heated Helically Coiled Steam Generators Tubes at Elevated Pressure, Int. J. Heat Mass Transfer, 24 (1981), 2, pp. 285-298
  24. Guo, L., Feng, Z., Chen, X., An Experimental Investigation of the Frictional Pressure Drop of Steam Two-Phase Flow in Helical Coils, Int. J. Heat Mass Transfer, 44 (2001), 14, pp. 2601-2610
  25. ***, REFPROP, NIST Standard Reference Database 23, Version 7.01, 2004
  26. Sami, S. M., Song, B., Heat Transfer and Pressure Drop Characteristics of HFC Quaternary Refrigerant Mixtures Inside Horizontal Enhanced Surface Tubing, App. Thermal Engg., 16 (1996), 6, pp. 461-473
  27. Chen, J. C., Correlation for Boiling Heat Transfer to Saturated Fluids in Convective Flow, Industrial and Engineering Chemistry, Process Design and Development, 5 (1966), 3, pp. 322-329
  28. Havas, G., Deak, A., Swainsky, J., Heat Transfer to Helical Coils in Agitated Vessels, The Chem Engg J., 35 (1987), 1, pp. 61-64

© 2021 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence