Thermo-hydraulic and economic performance of a parabolic trough solar collector equipped with finned rod turbulator and filled with oil-based hybrid nanofluid

Parabolic trough solar collector (PTSC) is one of the best solar thermal systems for producing thermal energy. PTSC works in medium and high temperature levels, and due to their wide range of industrial applications, improving their performance is very important. In the present study, a combination of thermal oilAl2O3-MWCNT (80%-20%) hybrid nanofluid and finned rod turbulator are employed to improve the performance of a PTSC. The Eulerian-Eulerian two-phase model is used to simulate the PTSC and assess its performance from thermo-hydraulic and economic viewpoints. Simulations are performed for different values of fin angle (g), rod diameter (D), fin pitch (Q) and Reynolds number (Re). The performance metrics considered to evaluate the collector performance include Nusselt number (Nu), friction factor, Performance Evaluation Criterion (PEC), Thermal Efficiency Enhancement (TEE) and cost. The obtained results revealed that the use of finned rod turbulator is useful for Re less than 12,000 and should not be used in larger values of Re as it weakens the overall hydrothermal performance of the PTSC. In addition, the economic analysis revealed that the novel geometry can save 14% on material usage. (c) 2021 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.