Modelling and Comparison of the Thermohydraulic Performance with an Economical Evaluation for a Parabolic Trough Solar Collector Using Different Nanofluids

Abstract

This study examines the three-dimensional heat transfer and flow characteristics of nanofluids in a parabolic trough solar collector under turbulent flow conditions, whereas a non-uniform focused heat flux was applied to the absorption pipe. CuO/water, Al2O3/water, TiO2/water, and SiO2/water are studied numerically. The dynamic and thermal fields are determined by the Reynolds number varying between 50000 ≤ Re ≤ 250000, while the volume concentration of nanofluids is the following: 3% CuO, 6% Al2O3, 4.82% SiO2 and 3.15% TiO2, the nanoparticle size of 30 nm by means of Finite Element Method (FEM). Effects of various parameters such as volume fraction of nanoparticles (φ), various Reynolds numbers and type of nanoparticle on thermo-hydraulic performance of the parabolic solar collector are studied. The average Nusselt number, heat transfer coefficient, average friction factor, pressure drop, temperature and velocity distribution are illustrated using four different types of nanofluids and four different volume fractions of nanoparticles with various Reynolds numbers. According to the final results, both TiO2 and CuO nanofluids have better performance in terms of thermal and hydraulic efficiency and evaluation economic performance compared with other nanofluids studied.