Energy and exergy analysis of an enhanced solar CCHP system with a collector embedded by porous media and nano fluid

N Tonekaboni,J Khaleghinia,M Eshagh Nimvari,H Salarian

doi:10.18186/thermal.990897

N Tonekaboni, J Khaleghinia + Show 2 more

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https://doi.org/10.18186/thermal.990897

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Abstract

The low efficiency of Collectors that absorb energy can be mentioned as one of the drawbacks in solar cogeneration cycles. In the present study, solar systems have been improved by adding porous media and Nanofluid to collectors. One advantage of using porous media and nanomaterials is to absorb more energy while the surface area is reduced. In this study, first, solar collectors are enhanced using 90% porosity copper in solar combined cooling, heating and power systems (SCCHP). Second, different percentages of CuO and Al2O3 nano-fluids are added to a flat plate and parabolic collectors to enhance thermal properties. Simulations are performed in different modes (simple parabolic collectors, simple flat plate collectors, improved flat plate collectors, parabolic collectors with porous media, and flat plate and parabolic collectors with different density of CuO and Al2O3 nanofluids). A case study is investigated for warm and dry regions with mean solar radiation Ib = 820 w / m2 in Iran. The maximum energy and exergy efficiencies are 60.12% and 18.84%, respectively, that is related to enhanced parabolic solar collectors with porous media and nanofluids. Adding porous media and nano-fluids increases an average 14.4% collector energy efficiency and 8.08% collector exergy efficiency.

Highlights

These days’ energy plays an important role in the economic growth of human societies
Based on the results presented in Figure. 7, the highest energy and exergy efficiencies are obtained in case 2 in which fully filled porous media parabolic solar collectors are used
One of the important points of this research is the replacement of simple flat plate solar collector filled with porous materials and using Al2O3 and CUO nanofluids instead of simple parabolic collectors, with this replacement the cost of cogeneration cycle is reduced due to the reduction of collector costs

Summary

Introduction

These days’ energy plays an important role in the economic growth of human societies. The amount of energy and exergy of the solar cogeneration cycles with flat and hyperbolic collectors in both base and improved modes with a porous material (copper foam with 90 percentage porosity) and Nanofluid with different percent’s calculated. 7, the highest energy and exergy efficiencies are obtained in case 2 in which fully filled porous media parabolic solar collectors are used.

Results

Conclusion