@article{MAKHILLJEAS202015319014,
    title = {Flow and Thermal Mechanisms in Receiver Tube of Parabolic Trough
Collectors with Rings Axially Connected Together and Radially
Connected to the Inner Tube Surface},
    journal = {Journal of Engineering and Applied Sciences},
    volume = {15},
    number = {3},
    pages = {762-772},
    year = {2020},
    issn = {1816-949x},
    doi = {jeasci.2020.762.772},
    url = {https://makhillpublications.co/view-article.php?issn=1816-949x&doi=jeasci.2020.762.772},
    author = {Ali Jaber,Nor,Mohd Zainal and},
    keywords = {Thermal mechanism,receiver tube,ring baffles inserted,parabolic trough collector,flow
mechanism,generated},
    abstract = {Artificial obstructions on the underside of receiver tubes can increase the heat transfer coefficient
between the receiver tubes (Heat Exchanger, HX) of Parabolic Trough Collectors (PTCs) and water as a
working fluid. In this study, we numerically and experimentally tested the behavior of laminar mixed
convective heat transfer in HX tube installed with baffles. These baffles are rings that are connected together
axially and connected radially to the inner tube surface. Using ANSYS fluent Version 15.0, we performed
computation fluid dynamics modeling to achieve heat transfer enhancement in HX tubes equipped with
turbulator baffles under laminar flow conditions. Moreover, the effects of Pitch ratio (P/D) = 3, 6 and 10 and
Reynolds number Re#480 were recorded. The novel application of the rings that are connected axially together
and radially to the inner tube surface contributes to the long-term storage of thermal energy and promotes heat
transfer via. conduction from the tube surface to the center line of the water flow within a short period. In the
study, the baffles generated a vortex to increase the Nusselt number (Nu) inside the HX. To simulate heat flux,
we calculated the constant wall heat flux of the receiver tube using an electric heater. Results indicated that
using 20 rings as baffles instead of plain tubes improves heat transfer by up to 75%. As P/D decreased and re
increased, the heat transfer rate, friction factor (f) and Thermal Enhancement Factor (TEF) increased.}
    }