Synergistic impact of tube configuration and working fluid on photovoltaic-thermal system performance

Abstract

The combined application of innovative designs and advanced heat-transfer fluids is a potential prospect for various heat-transfer applications. In this study, the effect of different working fluids on a photovoltaic thermal system implemented with a novel tube design is investigated. In ethylene glycol, CuO, MWCNT, and CuO/MWCNT hybrid nanofluids with volume concentrations up to 3% are synthesized, and their properties are experimentally evaluated. Moreover, the effect of different working fluids on the performance of the system is numerically studied in conjunction with the hybrid tube configuration. The experimental results indicate that CuO/MWCNT hybrid nanofluid demonstrates the highest enhancement in thermal conductivity and viscosity, at 36.5% and 34.2%, respectively. Moreover, compared to the straight tube configuration, the hybrid tube configuration demonstrates better performance, with improvements of 5.9% and 11.2% in electrical and overall effective efficiency, respectively. Additionally, this is coupled with an increase of 2% in the thermohydraulic performance. Furthermore, due to better thermophysical properties, the CuO/MWCNT hybrid nanofluid outperforms the mono nanofluids by demonstrating an improvement of 6.5% and 9.01% in electrical and overall effective efficiency, respectively, compared to ethylene glycol. However, the thermohydraulic performance is reduced by 0.75% compared to the base fluid.