Despite significant advancements in passive heat transfer enhancement techniques, optimizing turbulator geometries in constant-temperature pipes remains challenging, particularly in maximizing heat transfer performance while minimizing pressure losses. This study introduces a novel multi-twisted blade turbulator (MTBT), specifically designed to generate both swirling and radial flows simultaneously within a heat exchanger tube. A comprehensive numerical analysis was performed to assess the hydrothermal performance of the MTBT under varying geometric parameters, including the number of twisted blades (n=4–10), the twist ratio (y=0.25–1), and the blade width (w=1–4 mm). The originality of this work lies in its systematic evaluation of how these parameters impact the performance evaluation criterion (PEC), offering critical insights into the design space for passive heat transfer devices. The results demonstrate that increasing the number of twisted blades improves heat transfer, with an optimal configuration observed at n=6. Additionally, the twist ratio and the blade width strongly influence the intensity of the swirling flow as well as the pressure drop, with peak PEC values recorded at y=0.75 and w=3 mm. The highest PEC of 2.8 was achieved with the configuration y=0.75, n=6, and w=3 mm—outperforming all other tested geometries. This highlights the potential of the MTBT as an effective solution for improving thermal efficiency in applications such as HVAC systems, industrial heat exchangers, and energy conversion technologies.
