Korean Journal of Air-Conditioning and Refrigeration Engineering (설비공학논문집)

The Society of Air-Conditioning and Refrigerating Engineers of Korea (대한설비공학회)
권호 표지
DOI QR코드

DOI QR Code

Comparison of Exergy in a Refrigerating System using R404A and R134a for a Refrigeration Truck with Operating Conditions

운전조건에 따른 R404A와 R134a를 적용한 냉동탑차용 냉장시스템의 엑서지 비교

  • Shin, Yunchan (Graduate school of Mechanical Engineering, Chosun University) ;
  • Kim, Taejung (Graduate school of Mechanical Engineering, Chosun University) ;
  • Cho, Honghyun (Department of Mechanical Engineering, Chosun University)
  • 신윤찬 (조선대학교 기계공학과 대학원) ;
  • 김태중 (조선대학교 기계공학과 대학원) ;
  • 조홍현 (조선대학교 기계공학과)
  • Received : 2014.06.03
  • Accepted : 2014.09.01
  • Published : 2014.11.10
Download PDF
⟨ Previous Next ⟩

Abstract

The performances of refrigeration truck systems using R404A and R134a were investigated by experimental testing, and compared. The optimal COPs of the R404A and R134a systems were 2.96 and 3.42, when the refrigerant charge amount was 1.3 kg and 1.4 kg, respectively. When the indoor side air temperature increased from $5^{\circ}C$ to $9^{\circ}C$, the total exergy destruction rate of the R404A system was on average 39.1% higher than that of the R134a system. In addition, the exergy efficiency of the R404A system was 12.9% higher than that of R134a system, for various indoor air temperatures. When the outdoor side air temperature increased from $25^{\circ}C$ to $35^{\circ}C$, the total exergy destruction rate of the R404A and R134a systems decreased by 18.9% and 19.5%, respectively. In addition, the exergy efficiency of the R404A and R134a systems increased by 25.2% and 30.7%, respectively. As the compressor rotating speed increased, the COP of the R404A and R134a systems decreased by 23.6% and 18.4%. The total exergy destruction rate and exergy efficiency of the R404A system were 27.2% and 15.7% higher than those of R134a system, respectively. Compared to the R404A system, the R134a system showed a higher COP and a lower exergy destruction rate; thus it can be concluded that the R134a system has the better performance.

Keywords

References

  1. Mun, J. C., Choi, K. I., Oh, J. T., and Kim, J. H., 2009, Cooling characteristics of car refrigeration with heat storage, Proceedings of the SAREK 2009 Summer Conference, pp. 115-118.
  2. IIR, 2006, Refrigeration drives sustainable development, Report Card of IIR.
  3. UNEP, 1987, Montreal protocol on substances that deplete the ozone layer, United Nation Environmental Programme.
  4. Won, J. P., 2010, Response to the convention on climate change replacement car air conditioning system refrigerant technolocy trends, Magazine of SAREK, Vol. 39, No. 2, pp. 10-16.
  5. Mun, J. C., Choi, K. I., Oh, J. T., and Kim, J. H., 2009, Cooling characteristics of refrigerated vehicles with heat storage materials in thermobank, Proceedings of the SAREK 2009 Summer Conference, pp. 810-814.
  6. Peck, J. H., Park, S. S., Kim, Y. L., and Kim, S. C., 2002, Study on the performance characteristics of mechanical refrigeration truck vs. Hold-over refrigeration truck, Proceedings of the SAREK 2002 Summer Conference, pp. 339-344.
  7. Kim, S. H. and Cho, H. H., 2012, Performance comparison between R404A and R744 refrigeration system in refrigerating conditions, Proceedings of the SAREK 2012 Winter Conference, pp. 199-202.
  8. Oh, S. H., Youn, J. G., and Won, S. P., 2000, Performance experiment and Exergy analysis of an automotive air-conditioning system, Korean Journal of Air-Conditioning and Refrigeration Engineering, Vol. 12, No. 4, pp. 363-370.
  9. Li, G., Eisele, M, N., Lee, H. S., Hwang, Y, H., and Radermacher R. H., 2014, Experimental investigation of energy and exergy performance of secondary loop automotive air-conditioning systems using low-GWP (global warming potential) refrigerants, Energy, Vol. 68, No. 15, pp. 819-831. https://doi.org/10.1016/j.energy.2014.01.018
  10. ISO 15502, 2005, Household refrigerating appliancescharacteristics and test methods, International Organization for Standardization, Geneva, Switzerland.
  11. Cengel, Y. and Boles, M. A., 2011, Thermodynamics : an engineering approach, McGraw-Hill, 7th Edition, pp. 610-620.

Cited by

  1. Recent Progress in Air-Conditioning and Refrigeration Research: A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2014 vol.27, pp.7, 2015, https://doi.org/10.6110/KJACR.2015.27.7.380
  2. Investigation on the Performance of Special Purpose Automotive Air-Conditioning System Using Dual Refrigeration Cycle vol.40, pp.4, 2016, https://doi.org/10.3795/KSME-B.2016.40.4.213