Thermoeconomic Analysis of a Variable Refrigerant Flow System

Document Type : Research Article

Authors

Mechanical Eng. Department, Islamic Azad University, Kerman, Iran

Abstract

Exergy and thermoeconomic analysis is an effective method for determining thermodynamic characteristics and optimizing thermodynamic-economic performance of refrigeration systems. The present study deals with exergy and thermoeconomic analysis of a variable refrigerant flow system with four evaporators used in the dairy industry. A computer code written in EEs software was used for system simulation. Impact of three refrigerants, R502, R1234ze and R134a, on thermodynamic-economic parameters of the system was investigated. In addition to calculation of exergy efficiency of refrigeration cycle for three mentioned refrigerants, effect of evaporation and distillation temperature on system exergy degradation and exergy efficiency of was also investigated. Results showed that R1234ze gas can be appropriate alternative for R502 and R134a gases. Results show that exergy destruction in compressor in reference temperature from 3.974kW for R134a refrigerant increases to 4.221 kW for refrigerant R502. Exergy destruction in the condenser in second level was calculated for all refrigerants. In thermoeconomic analysis, costs of components of variable refrigerant flow system were investigated and total costs for R134a-R502-R1234ze refrigerants were studied. It was observed that a lowest cost is related to R502 refrigerant and total annual cost for or R134a and R1234ze refrigerants are in the next ranks.

Keywords

Main Subjects


[1] Stoeker W.F, Jones J.W., Refrigeration and air conditioning,  2nd ed., McGraw-Hill, Inc., USA, 1982.
[2]  Xia J., Winandy  E., Georges  B., Lebrun  J.,  “Experimental analysis of the  performances of variable refrigerant flow systems”,  Building Sevr Eng Res  Technol, Vol. 25( 1), pp. 17-23, 2004.
[3] Goetzler W., “Variable refrigerant flow systems”, ASHRAE Journal, April, 2007.
[4] Zhou Y.P., Wu J.Y., Wang R.Z., Shiochi, S., “Energy simulation in the variable refrigerant flow air-conditioning system under cooling conditions”, Energy and Buildings, Vol. 39, pp. 212-220, 2007.
[5] Zhou Y.P., Wu  J.Y., Wang  R.Z., Shiochi S.,  Li,  Y.M.,  “Simulation and experimental validation of the variable-refrigerant-volume (VRV) air-conditioning  system  in EnergyPlus”,  Energy and Buildings,  Vol. 40, pp. 1041-1047, 2008.
[6] Aynur T.N., Hwang Y.,  Radermacher,  R.,  “Simulation comparison of VAV  and VRF air conditioning systems in an existing  building for the cooling season”, Energy and Buildings, Vol. 41, pp. 1143-1150, 2009.
[7]  Wang X., Xia  J., Zhang  X., Shiochi  S., Peng  C.,  Jiang,  Y.,  “Modeling and  experiment analysis of variable refrigerant flow air-conditioning systems”, Proceedings of International IBPSA Conference, pp. 361-368, 2009.
[8]  Li  Y.M.,  Wu  J.Y.,  Shiochi,  S.,“Experimental validation of the simulation  module of the water-cooled variable refrigerant flow  system under cooling  operation”, Applied Energy, Vol. 87, pp. 1513-1521, 2010.
[9] Li Y.M., Wu J.Y., “Energy simulation and analysis of the heat recovery variable refrigerant flow system in winter”, Energy and Buildings, Vol. 42, pp. 1093-1099, 2010.
[10] Bettanini E., Gastaldello A.,  Schibuola L.,  “Simplified models to simulate  part load performances of air conditioning equipments”,  Proceedings of  International IBPSA Conference, Eindhoven, Netherlands, pp. 107-114, 2003.
[11] Krakow K.I.,“Relationships between irreversibility, exergy destruction, and  entropy generation for systems and components” ASHRAE Transactions, Vol. 100 ( 1), pp. 3-10, 1994.
[12] Stoecker W.F., “Internal performance of a refrigerant mixture in a two-evaporator refrigerator”, ASHRAE Transactions, Vol. 9 (1B), pp. 241–249, 2012.
[13] Zhu Y., Jin X., Du Z., Fan B., Fu S., “Generic simulation model of multi-evaporator variable refrigerant flow air conditioning system for control analysis”. Int. J. Refrigeration, Vol. 36, pp. 1602–1615, 2013.
 [14] Ansari N., Yadav B., Kumar J., “Theoretical exergy analysis of HFO-1234yf and HFO-1234ze as an alternative replacement of HFC-134a in simple vapour compression refrigeration system”. Int. J. Sci. Eng. Res. Vol. 4 (8), pp. 137–144. 2012.
[15] Babiloni M.A., Esbrí J.N., Barragán Á., Molés F., Peris B., “Drop-in energy performance evaluation of R1234yf and R1234ze (E) in a vapor compression system as R134a replacements”. Appl. Therm. Eng. Vol.71 (1), pp. 259–265, 2014.
[16] Behbahani-nia A., Shams S., “Thermoeconomic optimization and exergy analysis   of   transcritical   CO2 refrigeration   cycle with an ejector”. Energy Equipment and Systems, Vol. 4(1), pp.43–52, 2016.
[17] Shahryari Zanganeh O., Sarhaddi F., “Performance Investigation of a Single Effect (Libr-H2O) Absorption Cooling System connected to Photovoltaic Thermal Collectors”, Amirkabir Journal of Mechanical Engineering , DOI:10.22060/mej.2017.11728.5168. 2017. (In Persian)
[18] Keshtkar M.M., Talebizadeh P., “Multi-objective optimization of cooling water package based on 3E analysis: A case study”, Energy, Vol. 134, pp. 840-849, 2017.
 [19] Qiao H., Laughman C.R., Burns D.J., Bortoff S.A., “Dynamic Characteristics of an R410a Multi-split Variable Refrigerant Flow Air-conditioning System”, Heat Pump Conference, pp. 92–98, 2017.
[20] Yataganbaba A., Kilicarslan A., Kurtbas¸ “Exergy analysis of R1234yf and R1234ze as R134a replacements in a two evaporator vapour compression refrigeration system”. Int. J. Refrigeration, Vol. 60, pp. 26–37, 2015.
[21] Dincer I., Kanoglu M., Refrigeration systems and applications, 2nd ed. JohnWiley and Sons Ltd., UK. 2010.
[22] Kuppan T., Heat Exchanger Design Handbook, Marcel Dekker Inc, New York, 2000.
[23] Shah R.K., Dusan P. Fundamentals of heat exchanger Design, John Wiley & Sons, 2003.
[24] Kakaç S., Hangton L., Heat Exchanger: Selection, Rating and Thermal Design, John Wiley & Sons, 2002.
[25] Kays W. H., London A. L., Compact Heat Exchangers, third edition, McGraw-Hill, New York,1984.
[26] Bejan A., Tsatsaronis T., Moran M., Thermal Design and Optimization, John Wiley & Sons, 1995.
[27] Smith R., Chemical Process Design and Integration, John Wiley & Sons, University of Manchester, England, 2005.
[28] Catalogues of Evaporators and Condensers from Tabadol-Kar Industrial Company. (http://www.tabadolkar.com/products)