ICHEAS 8. ULUSLARARASI SAĞLIK, MÜHENDİSLİK VE UYGULAMALI BİLİMLER KONGRESİ, 15 - 17 Kasım 2024, ss.469-479
The
improvement of heat exchanger performance and efficiency has led researchers to
adopt various approaches to improve heat transfer. Turbulators represent a
widely used technique to create turbulent motion and increase heat transfer.
The use of different fluid types is another method that mainly aims to improve
the conductivity of the working fluid. Recently, many studies have focused on
improving heat exchanger performance by combining two methods, namely fluids
and turbulators. In the present study, the effects of V-shaped turbulators with
a step ratio P=1.5 placed in a circular analysis pipe under turbulent flow
conditions to improve heat exchanger performance using water fluid on heat
transfer coefficient and pressure drop were numerically investigated. Analyses
were carried out at six different Reynolds numbers under turbulent flow
conditions. The results of the empty pipe analysis were compared with the
correlations accepted in the literature. According to the obtained results, the
maximum error margins of the heat transfer and friction factor values of the
empty pipe according to Gnielinski and Blasius correlations were obtained as
3.47% and 13.61%, respectively. It was concluded that the heat transfer
coefficient and pressure drop were higher in the turbulated pipe compared to
the empty pipe. Thanks to the turbulators in the pipe, the fluid was
distributed from the pipe center to the walls. Thus, the contact between the
fluid and the pipe wall was increased. Therefore, the heat transfer was
increased due to the turbulators. In addition, a pressure difference occurred
between the pipe inlet and outlet. Depending on the increasing Re number, both
the heat transfer coefficient and the pressure drop increased. In general, the
V-shaped turbulated pipe provided higher heat transfer coefficient increases
between 6.42% and 8.59% and higher pressure drops between 86.51% and 87.70%
compared to the empty pipe for all Reynolds numbers, depending on the P=1.5
step ratio value used.