Performance analysis of a solar collector using nanofluids

The efficiency of energy and exergy is generally used as the most important parameter in order to introduce and compare the thermal systems of flat plate solar collectors. The first law of thermodynamics is not solely capable of demonstrating quantitative and qualitative performance of such systems, so the second law is required to illustrate the performances. In this paper, an analysis was done for heat transfer performance and exergy efficiency of flat plate solar collectors using four types of nanofluids, e.g. ZnO/water, CeO2/water, NiO and CoO/water. These nanofluids were used with different nanoparticle volume fractions in the range of 1% to 4%. Besides this, the present work also focuses on the performance of solar collector with different volume flow rates. Investigation consequences are also compared with the presently available literature for conventional solar collectors. The highest heat transfer performance and exergy efficiency were obtained for CeO2/water nanofluid among all nanofluids. NiO/water and CoO/water nanofluids represent almost same performance but higher than water. The results reveal that, CeO2/water nanofluid indicates maximum heat transfer with maximum exergy.