An experimental investigation on the simultaneous effects of helically corrugated receiver and nanofluids in a parabolic trough collector

• Published in: Journal of the Taiwan Institute of Chemical Engineers 2021-11, Vol.128, p.261-275
• Main Authors: Babapour, Morteza, Akbarzadeh, Sanaz, Valipour, Mohammad Sadegh
• Format: Article
• Language: English
• Subjects: Corrugated absorber tube; Nanofluid; Parabolic trough collector; Thermal efficiency; Thermal performance factor
• ISSN: 1876-1070; 1876-1089
• DOI: 10.1016/j.jtice.2021.07.031

•The progress about the usage of nanofluids and corrugated absorber tubes in a parabolic trough collector was assessed.•The results demonstrated that there is a rise of about 219.56% in the Nusselt number compared to the increase of 145.5% in the friction factor.•The use of corrugated tubes is a more effective thermal performance enhancement method than that of nanofluids. Improving performance of parabolic through collectors is one of the challenges in thermal application of solar energy. Nanofluids are one of the most effective methods that are used for heat transfer enhancement in the absorber of parabolic through collectors. Also, corrugated tubes can increase turbulence intensity and therefore heat transfer can experience a remarkable improvement. In this study, the effects of Al2O3/water nanofluid at volume fractions of 0.25-1% and helically corrugated absorber tubes with the pitch length of 3-7 mm and roughness height of 0.5-1.5 mm are investigated on the thermal behavior of a parabolic trough collector (PTC). All tests have been conducted under ASHRAE standard (93:2010). The results demonstrated an increase of about 219.56% in Nusselt number. In comparison, they showed an increase around 145.5% in friction factor. Also, at 1% vol. Al2O3/water nanofluids, the thermal performance factor reached the maximum value of 2.53% at the pitch length of 3 mm and roughness height of 1.5 mm. [Display omitted]