Journal of Energy Engineering (에너지공학)

The Korean Society for Energy (한국에너지학회)
권호 표지

Prediction and Experiment of Pressure Drop of R22 and R134a on Design Conditions of Condenser

응축기의 설계조건에서 R22와 R134a의 압력강하 예측 및 실험

  • Kang, Shin-Hyung (Department of Mechanical Engineering, Konyang University) ;
  • Byun, Ju-Suk (Yonsei Center for Clean Technology, Yonsei University) ;
  • Kim, Chang-Duk (Industry Academia Coop. Team, Korea Industrial Complex Corp)
  • Published : 2006.12.31
Download PDF
⟨ Previous Next ⟩

Abstract

An experimental study on the refrigerant-side pressure drop of slit fin an tube heat exchanger has been carried out. A comparison was made between the predictions of previously proposed empirical correlations and experimental data for the pressure drop on design conditions of condenser in micro-fin tube for R22 and Rl34a. Experiments were carried out under the conditions of inlet refrigerant temperature of $60^{\circ}C$ and mass fluxes varying from $150\;to\;250\;kg/m^{2}s$ for R22 and Rl34a. The inlet air conditions are dry bulb temperature of $35^{\circ}C$, relative humidity of 40% and air velocity varying from 0.68 to 1.43 m/s. Experiments show that pressure drop for R134a was $22{\sim}22.6%$ higher than R22 for the degree of subcooling $5^{\circ}C$ For the mass fluxes of $200{\sim}250\;kg/m^{2}s$, the deviation between the experimental and predicted values for the pressure drop was less than ${\pm}20%$ for R22 and Rl34a.

본 실험적 연구는 슬릿휜-관열교환기의 냉매측 압력강하에 대하여 수행하였다. 응축기의 설계조건에서 미세휜관내 냉매 R22와 R134a의 압력강하에 대한 실험데이터와 앞서 제안한 상관관계식과 상호 비교하였다. 실험은 냉매 R22와 Rl34a의 응축기 입구온도 $60^{\circ}C$, 질량유속 $150{\sim}250\;kg/m^{2}s$ 범위에서 수행하였다. 공기의 유입조건은 건구온도 $35^{\circ}C$, 상대습도 40%이며, 공기유속의 범위는 $0.68{\sim}1.43\;m/s$이다. 실험결과 응축기의 과냉도 $5^{\circ}C$ 조건에서 R134a의 압력강하는 R22보다 $22{\sim}22.6%$ 높게 나타났으며, 냉매의 질량유속 $200{\sim}250\;kg/m^{2}s$의 범위에서 실험으로부터 측정한 R22와 Rl34a의 압력강하는 예측결과와 ${\pm}20%$내에 일치하였다.

Keywords

References

  1. Fujii, K.; Itoh, N.; Innnami, T.; Kimura, H.; Nakayama N.; Yanugidi, T. 'Heat transfer pipe', US patent 4044797, assigned Hitachi Ltd, 1977
  2. Haraguchi, H.; Koyama, S.; Esaki, J.; Fujii, T. 'Condensation heat transfer of refrigerants HFC134a, HCFC123 and HCFC22 in horizontal smooth tube and a horizontal microfin tube', Proc., 30th National Symposia of Japan, Yokohama, 1993, 343-345
  3. Kedzierski, M.A.; Goncaves, J.M. 'Horizontal convective condensation of alternative refrigerant within a micro-fin tube', [NISTIR 6095], Gaithersburg (MD USA), NIST, 1997
  4. Pierre, B. 'Flow resistance with boiling refrigerants', ASHRAE J. September, Part 1, 1964, 58-65
  5. Cavallini, A.; Del Col D.; Doretti, L.; Longo, G.A.; Rossetto, L. 'Pressure drop during condensation and vaporization of refrigerants inside enhanced tube', Heat and Technology, 1997, 15, 3-10
  6. Friedel, L. 'Improved friction pressure drop correlation for horizontal and vertical two-phase pipe flow', European two phase flow group meeting, Ispra, Italy, Paper E2, 1979
  7. Newell, T.A.; Shah, R.K. 'Refrigerant heat transfer, pressure drop, and void fraction effects in microfin tubes', Proceeding 2nd International Symposia on Two-Phase Flow and Experimentation, vol. 3, Edizioni ETS, Italy, 1999, 1623-1639
  8. Souza, A.L.; Pimenta, M.M. 'Prediction of Pressure drop during horizontal two-phase flow of pure and mixed refrigerants', ASME Conference, Cavitation and multiphase flow, HTD-210, 1995, 161-171
  9. Choi, J.Y. 'Study on the prediction of pressure drop for condensation and evaporation of alternative refrigerants in micro-fin tube', Yonsei University, Seoul, Korea, 1999
  10. Choi, J.Y.; Kedzierski, M.A.; Domanski, P.A. 'Generalized pressure drop correlation for evaporation and condensation in smooth and microfin tube', International Proceeding of IIF-IIR Commision B1, Paderborn, Germany, 2001, B4, 9-16
  11. Kim, C.D.; Park, I.H.; Lee, J. 'Prediction and experiment of pressure drop of R22, R407C and R410A on design conditions of condenser', Korean J. Air-Conditioning and Refrigeration Engineering, 2004, 16(1), 42-53
  12. Kim, C.D.; Jeon, C.D.; Lee, J. 'Evaluation of airside heat transfer and friction characteristics on design conditions of condenser', Korean J. Air- Conditioning and Refrigeration Engineering, 2003, 15(3), 220-229
  13. ASHRAE, Fundamental Handbook (SI), 1993
  14. McLinden, M.O.; Klein, S.A.; Lemmon, E.W.; Peskin, A.P. 'Thermodynamic and transport properties of refrigerants and refrigerant mixtures database (REFPROP)', Ver. 6.01, NIST, 1998
  15. Collier, J.G.; Thome, J.R. 'Convective Boiling and Condensation', 3rd edition, Oxford University Press, 1994, 34-83
  16. Carnavos, T.C. 'Heat transfer performance of internally finned tube', Heat Transfer Engineering, 1980, 4, 32
  17. Kuo, C.C.; Wang, C.C. 'In-tube evaporation of HCFC-22 in a 9.52 mm micro/smooth tube', Int. J. Heat and Mass Transfer, 1996, 39, 2259-2269
  18. Geary, F.D. 'Return bend pressure drop in refrigeration system' ASHRAE Transactions, No. 1975, 2342, 252- 265
  19. Ito, H. 'Pressure loses in smooth pipe bends', Transaction of ASME, 1960, 3, 135
  20. Schlager, L.M.; Pate, M.B.; Bergles, A.E. 'Heat transfer and pressure drop during evaporation and condensation of R-22 in horizontal micro-fin tubes', Int. J. Refrigeration, 1989, 12, 6-14
  21. Fisher, S.K.; Rice, C.K. 'The Oak Ridge heat pump models: I, A steady-state computer design model for air-to-air heat pumps', ORNL/CON-80/R1, Oak Ridge National Lab, 1980
  22. Jung, D.S.; Radermacher, R. 'Performance simulation of single-evaporator domestic refrigerants charged with pure and mixed refrigerants', Int. J. Refrigerant, 1991, 14, 223-232 https://doi.org/10.1016/0140-7007(91)90007-4
  23. Cavallini, A.; Censi, D.; Del Col, L.; Doretti, L.; Longo, G.A.; Rossetto, L. 'Experimental investigation on condensation heat transfer and pressure drop of new HFC refrigerants', Int. J. Refrigeration, 2001, 24, 73-87 https://doi.org/10.1016/S0140-7007(00)00070-0