Abstract
In this study, a chiller system with an electronic expansion valve (EEV) and a thermostatic expansion valve (TXV) were compared from an energy saving view under variable and fixed speed compressor. The experimental chiller system under study has a variable speed scroll compressor, EEV and TXV, air cooled condenser and auxiliary equipments. The R134a was used in the compressor as a refrigerant. Although in variable speed chiller systems usually EEVs are used, in this study a TXV was also used to compare its performance. The results of the experimental studies show that the chiller system with EEV has 30% lower superheat value and 6% lower power consumption than the chiller system with TXV under variable speed operation. From the fixed speed compressor view, the chiller system with TXV performs 1.7% lower superheat value than the chiller system with EEV and, the chiller system with EEV has 8.5% higher compressor power consumption than TXV.References
Cengel YA, Boles AM. Thermodynamics: An Engineering Approach, sixth edition, McGraw Hill, New York 2006.
Dossat RJ, Horan TJ. Principles of refrigeration, fifth edition, Prentice Hall, New Jersey 2001.
Kim BH, O’Neal DL, Effect of refrigerant flow control on the heating performance of a variable-speed heat pump operating at low outdoor temperature. Journal of Solar Energy Engineering 2005; 127: 277-286. https://doi.org/10.1115/1.1849224
Lazzarin R, Noro M. Experimental comparison of electronic and thermostatic expansion valves performance in an air conditioning plant. International Journal of Refrigeration 2008; 31: 113-118. https://doi.org/10.1016/j.ijrefrig.2007.09.004
Chen W, Zhijiu C, Ruiqi Z, Yezheng W. Experimental investigation of a minimum stable superheat control system of an evaporator. International Journal of Refrigeration 2002; 25: 1137-1142. https://doi.org/10.1016/S0140-7007(01)00107-4
Aprea C, Mastrullo R, Renno C. Performance of thermostatic and electronic valves controlling the compressor capacity. International Journal of Energy Research 2006; 15: 1313-1322. https://doi.org/10.1002/er.1222
Ekren O. Fuzzy Logic Control of a Compressor and an Electronic Expansion Valve in a Chiller, PhD Thesis 2009.
Yiming C, Shiming D, Xiangguo X, Mingyin C. A study on the operational stability of a refrigeration system having a variable speed compressor. International Journal of Refrigeration 2008; 31(8): 1368-1374. https://doi.org/10.1016/j.ijrefrig.2008.04.012
Aprea C, Renno C. Experimental modeling of variable speed system. International Journal of Energy Research 2009; 33(1): 29-37. https://doi.org/10.1002/er.1468
Aprea C, Mastrullo R, Renno C. Determinations of the compressor optimal working conditions. Applied Thermal Engineering 2009; 29(10): 1991-1997. https://doi.org/10.1016/j.applthermaleng.2008.10.002
Sharma P. Electronic Expansion Valve (EEV) over traditional Thermostatic Expansion Valve (TEV) for Air conditioning and Refrigeration. LEEL Electricals Ltd., 2015.
Lamanna B. Electronic expansion valves reduce the significant energy losses due to cycling transients in refrigeration units with ON/OFF control. CAREL Industries 2016.
All the published articles are licensed under the terms of the Creative Commons Attribution Non-Commercial License (CC BY-NC 4.0) which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.