Pressure Drop in Two-Phase Flow Boiling of R134a, R123 and Their Mixture in Horizontal Tube

  • Lim, Tae-Woo (School of Mechatronics Engineering, Changwon National University)
  • Published : 2004.06.01


An experimental study on the pressure drop during flow boiling for pure refrigerants Rl34a and R123, and their mixture was carried out in a uniformly heated horizontal tube. Tests were run at a pressure of 0.6㎫ and in the ranges of heat flux 5-50㎾/$m^2$, vapor quality 0-100 percent and mass velocity of 150-600 kg/$m^2$s. Generally, the two-phase frictional multiplier is used to predict the frictional pressure drop during the two-phase flow boiling. The obtained results have been compared to the existing various correlations for the two-phase multiplier. Also, the frictional pressure drop was compared to a few available correlations; The Lockhart-Martinelli correlation considerally overpredicted the frictional pressure drop data for mixture as well as pure components in the entire mass velocity ranges employed in the present study, while the Chisholm correlation underpredicted the present data. The Friedel correlation was found to satisfactorily correlate the frictional pressure drop data except for a low quality region.



  1. Collier, J.G. and Thome, J.R., 1994, Con-vective Boiling and Condensation, 3rd ed.,Oxford University Press, London
  2. Pierre, B., 1964, Flow resistance with boiling refrigerants, ASHRAE Trans., pp. 58-77
  3. Lockhart, R.W. and Martinelli, R. C., 1949, Proposed correlation of data for isothermal two-phase, two-component flow in pipes, Chemical Engineering Progress, Vol. 45, pp.39-48
  4. Martinelli, R.C. and Nelson, D.B., 1948, Pre-diction of pressure drop during forced-cir-culation boiling of water, Trans. of American Society Mechanical Engineers, Vol. 70, pp.695-702
  5. Jung, D.S. and Radermacher, R., 1989, Pre-diction of pressure drop during horizontalannular flow boiling of pure and mixed re-frigerants, International Journal of Heat and Mass Transfer, Vol.32, pp.2435-2446
  6. Nishiumi, H. and Saito, S., 1977, Correlation of the binary interaction parameter of the modified generalized BWR equation of state, Journal of Chemical Engineering of Japan, Vol. 10, pp.176-180
  7. Reid, R.C., Prausnitz, J.M. and Sherwood, T. K., 1977, The Properties of Gases and Liquids, 3rd ed., Mcgraw-Hill, New York
  8. Singal, L.C., Sharma, C.P. and Vanna, H.K., 1983, Pressure drop during forced con-vection boiling of binary refrigerant mix-tures, Int. J Multiphase Flow, Vol. 9, pp.309-323
  9. Chisholm, D., 1967, A theoretical basic for the Lockhard-Martinelli correlation for two-phase flow, International Journal of Heat and Mass Transfer, Vol.10, pp.1767-1778
  10. Chisholm, D., 1973, Pressure gradients due to friction during the flow of evaporating two-phase mixtures in smooth tubes and channels, International Journal of Heat and Mass Transfer, Vol.16, pp.347-358
  11. Friedel, L., 1979, Improved friction pressure drop correlations for horizontal and vertical two-phase pipe flow, Presented at the European Two-phsae Flow Group Meeting, Ispra, Italy, Paper E2, June, Vol.18, pp.485-492
  12. Premoli, A., Francesco, D. and Prina, A., 1970, An empirical correlation for evaluating two-phase mixture density under adiabatic conditions, European Two-Phase Flow Group Meeting, Milan
  13. Whalley, P.B., 1987, Boiling Condensation and Gas-Liquid Flow, Oxford University Press