Exergy Based Performance Analysis of a Solid Adsorption Solar Refrigerator

Abstract

The exergy based performance analysis of a solid adsorption solar refrigerator is presented. The analysis is based on an exergy balance applied to each component of the refrigeration machine, leading to a general exergy balance equation. The dead state temperature was chosen to coincide with the ambient temperature. Results reveal that maximum exergy destruction occurred in the collector/generator/adsorber during heat up and adsorbate desorption phases with a value of 3747.77 kJ. Values recorded in the condenser and evaporator were 10.51 and 20.11 kJ, respectively while the exergy efficiency was in the range of 0.0008 – 0.012. It was also found that the rate of exergy destruction reduced as soon as adsorbate generation commenced; indicating superior energy and exergy utilization during desorption phase. Thus use of adsorbent and adsorbate with the potential of very early commencement of desorption can significantly improve the exergetic efficiency of the system.

Keywords

• Exergy, Solar, Adsorption, Refrigerator

References

1. C. Hilbrand, D. Philippe, M. Pons and F. Buchter, “A new solar powered adsorption refrigerator with high performance. Solar Energy, vol. 77, No. 3, pp. 311 – 318, 2004.
2. E. E. Anyanwu and C. I. Ezekwe, “Design, construction and test run of a solid adsorption solar refrigerator using activated carbon/methanol as adsorbent/adsorbate pair”, Energy Conversion and Management, vol. 44, pp. 2879 – 2892, 2003.
3. E. E. Anyanwu and N. V. Ogueke, “Thermodynamic Design
4. Refrigerator”, Renewable Energy, vol. 30, pp. 81 – 96, 2005. Solid Adsorption
5. Solar [4] E. E. Anyanwu and N. V. Ogueke, “Transient Analysis and Performance Prediction of a Solid Adsorption Solar Refrigerator”, Applied Thermal Engineering, vol. 27, pp. 2514 – 2523, 2007.
6. E. E. Anyanwu, U. U. Oteh and N. V. Ogueke, “Simulation of a solid adsorption solar refrigerator using activated carbon/methanol adsorbent/adsorbate pair”, Energy Conversion and Management, vol. 42, pp. 899 – 915, 2001.
7. E. E. Vasilescu, R. Boussehain, M. Feidt, and A. Dobrovicescu, “Energy and exergy optimization of the adsorption refrigeration machine with simple and double effect”, TERMOTEHNICA, vol.1- 2, pp. 80 – 86, 2007.
8. F. Lemmini and A. Errougani, “(2005). Building and experimentation

9. refrigerator”, Renewable Energy, vol. 30, pp. 1989 – 2003, 2005. solar powered
10. adsorption [8] H. Z. Hassan, A. A. Mohamad and R. Bennacer, “Simulation of an adsorption solar cooling system”, Energy, vol. 36, No. 1, pp. 530 – 537, 2011.
11. Hu, Jing and R. H. B. Exell, “Simulation and sensitivity analysis of intermittent solar powered charcoal/methanol refrigeration” Renewable Energy, vol. 4, No. 1, pp. 133 – 149, 1994. [10]
12. I. Dincer and A. R. Marc, Exergy, Energy, Environment and Sustainable Development, 2nd Ed., Oxford:Elsevier Ltd., 2013. [11]
13. Li, M. and Wang, R.Z. (2003). Heat and mass transfer in a flat plate solar solid adsorption refrigeration ice maker. Renewable Energy, 28 (4), pp. 613 – 622. [12]
14. M. Li, M. B. Huang, H. B. R. Z. Wang, L. L. Cai, W.D. and Yang, W.M. (2004). Experimental study on adsorbent of activated carbon with refrigerant of methanol and ethanol for solar ice maker. Renewable Energy, 29, pp. 2235 – 2244. [13]
15. M. Pons, F. Meunier, G. Cacciola, R. E. Critoph, M. Groll, L. Puigjaner, B. Spinner and F. Ziegler, “Thermodynamic based comparison of sorption systems for cooling and heat pumping”, International Journal of Refrigeration, vol. 22, pp. 5 – 17, 1999. [14]
16. N. V. Ogueke and E. E. Anyanwu, “Design improvements for a collector/generator/adsorber of a solid adsorption solar refrigerator”, Renewable Energy, vol. 33, pp. 2428 – 2440, 2008. [15]
17. R. E. Critoph, “An ammonia carbon solar refrigerator for vaccine cooling”, Renewable Energy, vol. 5, No(1 – 4), pp. 502 – 508, 1994. [16]
18. R. Z. Wang, Z. Z. Xia, L. W. Wang, Z. S. Lu, S. L. Li, T. X. Li, J. Y. Wu, and S. He, “Heat transfer design in adsorption refrigeration systems for efficient use of low- grade thermal energy”, Energy, vol. 36, No. 9, pp. 5425 – 5439, 2011. [17]
19. V. Baiju and C. Muraleedharan, “Exergy Stage Assessment
20. Refrigeration System Using ANN”, International Scholarly Research Network Mechanical Engineering, pp. 1 – 10, 2012. Solar Adsorption [18]
21. V. Baiju and C. Muraleedharan, “Energy and exergy analysis of solar hybrid adsorption refrigeration system”, International Journal of Sustainable Engineering, vol. 6, No. 4, pp. 289 – 300, 2013. [19]
22. Y. L. Zhao, E. Hu and A. Blazewicz, “A non- uniform pressure and transient boundary condition based dynamic modeling of the adsorption process of an adsorption refrigeration tube”, Applied Energy, vol. 90, No. 1, pp. 280 – 287, 2012. [20]
23. Y. You, E. Hu and J. Jarvis, “The Exergy (Availability) Analysis on the Solar Adsorption Refrigeration System Working around the Atmospheric Pressure” In David Mills, John M. Bell, Stoynov LA and Prasad
24. Proceedings of the 38th Annual Conference of the Australian and New Zealand Solar Energy Society, Brisbane, Australia. pp. 340 – 347. SOLAR 2000.