Thermoeconomic optimization and exergy analysis of transcritical CO2 refrigeration cycle with an ejector

Document Type : Research Paper

Authors

Mechanical Engineering Department, K.N. Toosi University of Technology Tehran, Tehran, Iran

Abstract

The purpose of this research is to investigate thermoeconomic optimization and exergy analysis of transcritical CO2 refrigeration cycle with an ejector. After modeling thermodynamic equations of elements and considering optimization parameters of emerging temperature of gas of cooler (Tgc) , emerging pressure of cooler's gas (Pgc) , and evaporative temperature (Tevp) , optimization of target function is done. Target function indicates total expenses of the system during a year which is consisted of expenses of entering exergy and spending on the system's equipment. Optimized amplitude of decision variables are gained by the balance between the entering exergy and yearly initial capital investing. Results indicate reduction in yearly total expenses of system (34%) and enhancement in thermodynamic functionality coefficient and exergetic efficiency in optimum point toward end point.

Keywords

References

[1]Kornhauser, A. A.,  The Use of an Ejector as a Refrigerant Expander, Proceedings of the 1990 USNC/IIR–Purdue Refrigeration Conference  (1990) 10-19.
[2]Ozaki Y, Takeuchi H, Hirata T., Regeneration of Expansion Energy by Ejector in CO2 Cycle. Proceedings of Sixth IIRG. Lorentzen Natural Working Fluid Conference (2004) 142-149
[3]Working group, Intergovernmental Panel on Climate Change. Climate Change  (2001).
[4]Neksa P., CO2 Heat Pump Systems, International Journal of Refrigeration (2002) 25: 421–7.
[5]Kim M.H., Pettersen J., Bullard C.W., Fundamental Process and System Design Issues in CO2 Vapor Compression Systems, Progress in Energy and Combustion Science (2004) 30: 41-49.
[6]Liu JP, Chen JP, Chen ZJ, Thermodynamic Analysis on Trans-Critical R744 Vapor Compression/Ejection Hybrid Refrigeration Cycle, Proceedings of Fifth IIR G. Lorentzen Conference on Natural Working Fluids, Guangzhou (2002).
[7] Fangtian S., Yitai M., Thermodynamic Analysis of Transcritical CO2 Refrigeration Cycle with an Ejector, Tianjin Conference, China(2010).
[8] Elbel S.W., Hrnjak P.S., Effect of Internal Heat Exchanger on Performance of Transcritical CO2 Systems with Ejector, Tenth International Refrigeration and Air Conditioning Conference at Purdue,West Lafayette (2004).
[9] Ozaki Y., Takeuchi H., Hirata T., Regeneration of Expansion Energy by Ejector in CO2 Cycle, Proceedings of Sixth IIRG. Lorentzen Natural Working Fluid Conference, Glasgow, UK (2004).
[10] Sarkar J., Ejector Enhanced Vapor Compression Refrigeration and Heat Pump Systems-A Review, Department of Mechanical Engineering. Indian Institute of Technology (B.H.U.), India (2012).
[11]Li D, Groll E.A., Transcritical CO2 Refrigeration Cycle with Ejector-Expansion Device, International Journal Refrigeration (2005) 28: 766–73.
[12]Valero, A., CGAM problem: definition and conventional solution. Energy,(1994) 19. pp 268-279.
[13]Selbas R., Kızılkan O., Sencana A.,  Economic Optimization of Subcooled and Superheated Vapor Compression, Energy (2006) 31: 2108-2128
[14] E1-Sayed Y.M., Designing Desalination Systems for Higher Productivity, Advanced Energy Systems Analysis,  Higgins Way, Fremont, USA (2005).
Energy Equipment and Systems
Volume 4, Issue 1
June 2016
Pages 43-52

Files

Share

How to cite

Statistics