Heat transfer enhancement in a double-pipe helical heat exchanger using spring wire insert and nanofluid

Sharaf, Maisa A.; Marzouk, S. A.; Aljabr, Ahmad; Almehmadi, Fahad Awjah; Kaood, Amr; Alqaed, Saeed

doi:10.1007/s10973-024-12992-1

Cited by 4 publications

(1 citation statement)

References 56 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A pressure-based scheme is employed to achieve a steady state case after completing the three-dimensional model, which is then imported into Fluent. The realizable k-ɛ is chosen for the turbulent model, depending on prior research on different turbulence models for DTHXs through standard wall function 54 . Velocity inlets are set at the inlets of the internal side and annulus side, while pressure outlets are assigned at the outlets of the tube and the shell sides.…”

Section: Boundary Conditions and Cfd Proceduresmentioning

confidence: 99%

Numerical and experimental investigation of heat transfer enhancement in double tube heat exchanger using nail rod inserts

Marzouk,

Almehmadi,

Aljabr

et al. 2024

Sci Rep

Self Cite

View full text Add to dashboard Cite

The Double-tube heat exchanger (DTHX) is widely favored across various industries due to its compact size, low maintenance requirements, and ability to operate effectively in high-pressure applications. This study explores methods to enhance heat transfer within a DTHX using both experimental and numerical approaches, specifically by integrating a nail rod insert (NRI). A steel nails rod insert, 1000 mm in length, is introduced into the DTHX, which is subjected to turbulent flows characterized by Reynolds numbers ranging from 3200 to 5700. Three different pitches of NRI (100 mm, 50 mm, and 25 mm) are investigated. The results indicate a significant increase in the Nusselt (Nu) number upon the insertion of nail rods, with further improvements achievable by reducing the pitch length. Particularly noteworthy is the Nu number enhancement ratio for the 25 mm pitch NRI, which is 1.81–1.9 times higher than that for the plain tube. However, it is observed that pressure drop increases in all configurations with NRI due to heightened turbulence and obstruction by the NRI. Among the various pitch lengths, the 25 mm pitch exhibits the highest pressure drop values. Moreover, exergy efficiency is found to improve across all cases with NRI, corresponding to increased heat transfer, with the 25 mm pitch length showing a remarkable 128% improvement. Numerical analysis reveals that the novel insert enhances flow turbulence through the generation of secondary flows, thereby enhancing heat transfer within the DTHX. This study provides a comprehensive analysis, including temperature, velocity, and pressure drop distributions derived from numerical simulations.

show abstract

Section: Boundary Conditions and Cfd Proceduresmentioning

confidence: 99%