###### Abstract
They used a twisted tape with a pitch ratio of 2.0 and a hybrid nanofluid with a 0.04 volume fraction. In these experiments, the hybrid nanofluid performed excellently in terms of Nusselt number, heat transfer coefficient, and friction factor. Moreover, as the Reynolds number increases, axial convection becomes greater, optimizing heat transfer, disturbing the boundary layer, and thereby enhancing heat transfer from the wall to the fluid. [PERSON] et al. [6] examined the performance of tubes with a full-length single twisted tape, full-length double-tapes, and double-spaced tapes with varying twist and space ratios (space length-to-tube diameter). Their research illustrated that double-tapes and/or double-spaced tapes with a smaller space ratio (0.75) perform the greatest heat transfer performance. This was due to more complex swirl flow and greater fluid mixing, which augmented heat transfer. [PERSON] and [PERSON] [7] evaluated the fluid dynamics and thermohydraulic performance of a tube with twisted tapes employing circular protuberances (CPTTs). The twist ratio was fixed, and tapes were installed in an isothermal tube. They indicated that a twisted tape with circular protuberances provided a 1.5 times greater thermal augmentation factor than a typical twisted tape (TT). Its Nusselt number and friction factor were 15-24% and 12-22% higher than those of a TT, respectively. [PERSON] and [PERSON] [8] conducted a numerical study on double-pipe thermal exchangers utilizing W-cut twisted tapes to improve heat transfer performance. W-cut twisted tapes with 0.2-0.6 depth-to-width ratios were tested. These results observed that the vortices produced by the twisted tapes enhanced heat transfer, and increasing the cutting depth intensified turbulence and improved fluid mixing. The thermal performance factor increased with cutting depth, reaching its maximum value of 1.5. The W-shaped cut twisted tape exhibited a superior performance at high Reynolds numbers. [PERSON] et al. [9] investigated heat transfer enhancement in a tube by twisted trapezoidal and trapezoidal tapes. Their results showed that under an isothermal condition with Reynolds numbers ranging from 5000 to 25,000, the twisted trapezoidal tapes improved not only thermal transfer but also increased pressure losses. Twisted trapezoidal tapes showed an overall performance factor greater than unity. The highest Nusselt number, 118, and overall performance factor, 1.16, were obtained by employing twisted trapezoidal tapes with a thread height of a quarter of the tape's width and an 80\({}^{\circ}\) twisted pitch length that was 4.0 times the inner diameter. Their results indicated that twisted trapezoidal tapes combined the advantages of twisting and trapezoidal shapes performed well in turbulent heat transfer. [PERSON] et al. [10] carried out the effect of twisted tapes with dimples on heat transfer, demonstrating both considerably improved thermal transfer with a moderately increased pressure drop. The dimpled tape had better performance on the dimpled and protrusion sides compared to a typical twisting tape. The heat transfer was improved with a smaller twist ratio and deeper dimples. The highest thermal performance was achieved with a 3.0 twist ratio and a 0.3 dimple depth to tube diameter ratio. Turbulence intensity in the depressions was markedly increased, particularly at the tube wall and in the core region, potentially resulting in intensified secondary flows and thus enhanced heat transfer. [PERSON] et al. [11] performed the thermal and frictional behaviors of water flowing through a dual-pipe heat exchanger installed with twisted tapes. They are tested with various dimple ratios, maintaining a 5.5 twist ratio. They revealed that the heat transfer increased with the Reynolds number, while the best configuration for a higher heat transfer rate was at a \(D/H\) of 3.0 among different diameters. The friction factor was lowest when the diameter-to-depth ratio was 4.5.