Impact of new multiple twisted tapes on treatment of solar heat exchanger
Department of Mechanical Engineering, Babol Noshirvani University of Technology, Babol, Iran
2 Renewable Energy Systems and Nanofluid Applications in Heat Transfer Laboratory, Babol Noshirvani University of Technology, Babol, Iran
3 Department of Civil and Environmental Engineering, University of Pittsburgh, Pittsburgh, PA, USA
Accepted: 8 November 2021
Published online: 3 January 2022
This study investigates the nanofluid turbulent flow due to the presence of helical tapes in solar flat plate collectors. The influence of various twisted tap (TT) and inlet velocity on the thermal efficiency and Darcy factor value of the nanofluid flow is evaluated. Furthermore, the effect of nanoparticle shape on thermal efficiency of solar heat exchanger is studied. The results imply that more mixing occurs in larger values of TTn and Re. Although augmenting TTn results in higher pressure loss, thermal efficiency improves with the rise of TTn. According to achieved outcomes, using twisted tapes notably improves the Nu. As the shape of the nanoparticles changes from spherical to blade form, the heat transfer enhances about 12.12% in solar heat exchanger. Performance (η) augments with rise of shape factor and with changing from sphere to blade shape, η augments about 17.26%. Increase of power of pump makes η to decrease about 9.06%. Utilizing more number of tapes causes η to decline about 2.27%. Increasing inlet velocity and number of tapes leads to augment of Nu about 264.12% and 3.19%.
© The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2022