Numerical Investigations of parabolic trough collectors using different nanofluids

Document Type : Original papers

Authors

1 Department of Mechanical, Aerospace, and Civil (MACE) engineering, school of Engineering University of Manchester Manchester, UK

2 Department of Mechanical Engineering, College of Engineering, Khalifa University of Science and Technology, Abo Dhabi, UAE, imran.afgan@ku.ac.ae Department of MACE, school of Engineering University of Manchester, Manchester, UK

3 Department of MACE, school of Engineering University of Manchester Manchester, UK

4 Faculty of Energy Engineering - Aswan University - Aswan - Egypt

Abstract

This paper presents three-dimensional numerical simulations of parabolic trough collectors (PTC) based on two
low-Reynolds eddy viscosity turbulence models, namely; Launder and Sharma k-epsilon and k-omega SST models. For
the simulations, water was used as the Heat Transfer Fluid (HTF) with four different nanoparticles; Al2O3, TiO2, CuO and
Cu. Different volume fractions (φ) of the nanoparticles were investigated for various Reynolds (Re) numbers with uniform
heat flux. Results showed that the overall performance of the system is more sensitive to changes in the thermal properties of nanofluids than the thermal properties of the HTF. At a volume fraction of 6% and a Re number of 70,000, the Nusselt number (Nu) enhancement of nanofluids TiO2-water, Al2O3-water, CuOwater, and Cu-water were found to be 21.5%, 20.2%, 18.11%, and 15.7% respectively while the performance evaluation criteria (PEC) were 1.214, 1.2, 1.18 and 1.155 respectively.