Enhancing heat transfer in tube heat exchanger containing water/Cu nanofluid by using turbulator

Abstract

In the current essay, the numerical investigation of heat transfer in an exchanger containing nanofluid with Cu nanoparticles in the presence of a new inserter is carried out. The equations governing the turbulent fluid flow have been solved utilizing single-phase models with the aid of the finite volume method in ANSYS-FLUENT software using the k-ε turbulence model for the Re number ranging from 4000 to 8000. Furthermore, the influence of Reynolds number, nanoparticle volume fraction, and geometric characteristics of turbulator on the friction factor and Nusselt number have been scrutinized. Outcomes reveal that the newly introduced inserter performs well and increases the Nusselt number by roughly 34–54 times and the friction coefficient by approximately 1.8–3.2 times compared to the smooth tube. It is also observed that a 2 % increase in the nanoparticles volume fraction has resulted in a rise in the Nusselt number by around 92 %. To attain the optimal performance of the presented turbulator, the longitudinal distance between the inserters is recommended as S/D = 5.27, for which Performance evaluation criteria values in the range of 3.01–9.23 in the Reynolds range under investigation are acquired.