JASIC Volume. 1, Issue 1 (2020)

The harmful effects of fossil fuels on the environment and continuous growth in the energy demand across the world due to the prosperous population have made it essential to harness renewable energy through different technologies. The heat transfer fluids used in solar thermal systems are fundamental to enhance the higher effectiveness of solar thermal systems. This paper presents a comparative analysis of the influence of the thermo-physical properties of CuO, Al₂O_3, and TiO₂ water-based nanofluids on the thermal performance of the Parabolic Trough Solar Concentrator, PTSC. The energy governing equations of nanofluids, coupled with the concentrator’s effectiveness equations were solved using iterative relaxation approach. C++ program is developed to examine the impact of the thermal characteristics of the three water-based nanofluids on the heat distribution and performance of the concentrator with varying sizes of nanoparticle in the range 1% ≤ φ ≤ 10% at 0.2 kg/s mass flow rate value. The results reveal that the heat transfer coefficient is expanding by 20%, 21%, and 14%, and thermal efficiencies are diminishing by 9%, 56% and 33% using TiO₂, CuO and Al₂O₃ respectively, with the density increase by 28 %, the thermal conductivity increase by 23 %, and the specific heat capacity reduce by 30 %. The influence of the thermo-physical properties of the water-based nanofluids on the heat transfer coefficient and the efficiency of the PTSC are significant.  This work indicates that the suspended nanoparticles significantly change the thermal characteristics of the suspension which determines its applications.