An Experimental Study on the Performance of Air/Water Direct Contact Air Conditioning System

  • Yoo, Seong-Yeon (Department of Mechanical Design Engineering, Chungnam National University) ;
  • Kwon, Hwa-Kil (Graduate School, Chungnam National University)
  • Published : 2004.06.01

Abstract

Direct contact air conditioning systems, in which heat and mass are transferred directly between air and water droplets, have many advantages over conventional indirect contact systems. The purpose of this research is to investigate the cooling and heating performances of direct contact air conditioning system for various inlet parameters such as air velocity, air temperature, water flow rate and water temperature. The experimental apparatus comprises a wind tunnel, water spray system, scrubber, demister, heater, refrigerator, flow and temperature controller, and data acquisition system. The inlet and outlet conditions of air and water are measured when the air contacts directly with water droplets as a counter flow in the spray section of the wind tunnel, and the heat and mass transfer rates between air and water are calculated. The droplet size of the water sprays is also measured using a Malvern Particle Analyzer. In the cooling conditions, the outlet air temperature and humidity ratio decrease as the water flow rate increases and as the water temperature, air velocity and temperature decrease. On the contrary, the outlet air temperature and humidity ratio increase in the heating conditions as the water flow rate and temperature increase and as the air velocity decreases.

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References

  1. Bohn, M. S., 1985, 'Air Molten Salt Direct-Contact Heat Exchange,' J. of Solar Energy Engineering, Vol. 107, pp. 208-214 https://doi.org/10.1115/1.3267680
  2. Ismail, I. M. and Mahmoud, K. G., 1994, 'Comparative Study of Different Air Conditioning Systems Incorporating Air Washers,' Int. J. of Refrigeration, Vol. 17, No. 6, pp. 364-370 https://doi.org/10.1016/0140-7007(94)90070-1
  3. Jacobs, H. R., 1988, 'Direct-Contact Heat Transfer for Process Technologies,' J. of Heat Transfer, Vol. 110, pp. 1259-1270 https://doi.org/10.1115/1.3250625
  4. Kang, Y. H., Kim, N. J., Hur, B. K. and Kim, C. B., 2002, 'A Numerical Study on Heat Transfer Characteristics in a Spray Column Direct Contact Heat Exchanger,' KSME Int. J., Vol. 16, No. 3, pp. 344-353 https://doi.org/10.1007/BF03185232
  5. Kim, N. J., Kim, C. B., Seo, T. B. and Hur, B. K., 2001, 'Performance of a Direct Contact Heat Exchanger with Meshes for a Solar Thermal Energy System,' KSME Int. J., Vol. 15, No. 2, pp. 268-276
  6. Lee, H. C., Bang, K. H. and Kim, M. H., 1998, 'Experimental Study on the Thermal Performance of a Cooling Tower,' Korean J. of Air-Conditioning and Refrigeration Engineering, Vol. 10, No. 1, pp. 88-94
  7. Seetharamu, K. N. and Battya, P., 1989, 'Direct Contact Evaporation between Two Immiscible Liquids in a Spray Column,' J. of Heat Transfer, Vol. 111, pp. 760-785 https://doi.org/10.1115/1.3250748
  8. Siqueiros, J. and Bonilla, O., 1999, 'An Experimental Study of a Three-Phase, Direct-Contact Heat Exchanger,' Applied Thermal Engineering, Vol. 19, pp. 477-493 https://doi.org/10.1016/S1359-4311(98)00068-4
  9. Int. J. Heat Mass Transfer v.30 no.9 Vaporization of a Liquid by Direct Contact in Another Immiscible Liquid Tadrist,L.;Shehu Diso, I.;Santini,R.;Pantaloni,J. https://doi.org/10.1016/0017-9310(87)90237-7
  10. Tadrist, L., Shehu Diso, I., Santini, R. and Pantaloni, J., 1987, 'Vaporization of a Liquid by Direct Contact in Another Immiscible Liquid,' Int. J. Heat Mass Transfer, Vol. 30, No. 9, pp. 1773-1785 https://doi.org/10.1016/0017-9310(87)90237-7
  11. Warrington, R. O. and Mussulman, R. L., 1983, 'Analysis of a Liquid/Gas Direct Contact Heat Exchanger Concept,' J. of Energy, Vol. 7, pp. 732-734 https://doi.org/10.2514/3.62723
  12. Yoo, S. Y., Kwon, H. K. and Kim, K. Y., 2004, 'Performance Analysis of Water/Air Direct Contact Air Conditioning System,' Korean J. of Air-Conditioning and Refrigeration Engineering, Vol. 16, No. 2, pp. 175-183