Akademik Veri Yönetim Sistemi
EXPERIMENTAL HEAT TRANSFER, cilt.1, ss.1-23, 2024 (SCI-Expanded)
In industrial applications, annular fins are commonly made of homogeneous materi-
als such as aluminum, struggling to provide uniform temperature distribution along
their length. Recognizing the potential of Functionally Graded Materials (FGMs) to
enhance thermal performance by combining two different materials with a gradual
variation, this study proposes their use as fin materials to achieve optimum per-
formance. The study consists of three major components: (1) numerical analyses to
determine the optimum volume composition of FG fins, (2) the fabrication process of
aluminum and FG fins utilizing powder metallurgy and the hot-pressing technique,
and (3) experiments to evaluate the thermal performance of FG and aluminum fin
arrays attached to a horizontal cylinder of 250 mm length under natural convection.
Heat ranging from 25 W to 150 W was applied to the cylinder during these experi-
ments. Based on the experiments, the thermal performances of fins were evaluated
in terms of net free convection heat transfer rate, the Nusselt number, and fin ef-
fectiveness. Overall, experimental results demonstrate that the net convection heat
transfer rate depends on fin spacing, material, and the base-to-ambient temperature
difference. Specifically, FG fin arrays enhance the net heat transfer rate by 59%,
while aluminum fin arrays increase it by 33% compared to finless cylinders. More-
over, FG fins outperform aluminum fin arrays by 40% in convective heat transfer
coefficient h. Due to being the first experimental study, this study sets itself apart.