Hydrothermal behavior of a novel conical twisted strip turbulator in a heated tube: A numerical analysis

The increasing use of heated pipes and heat exchangers has created a pressing need to enhance thermal efficiency. This research introduces a novel turbulator design known as the conical twisted strip turbulator. The turbulator design resembles a cone and is composed of several twisted strip tentacles. This unique configuration is expected to generate strong rotational and radial flow patterns, leading to enhanced heat transfer. A numerical analysis was conducted using the RNG k-epsilon model to investigate various geometric parameters of the turbulator. The study examined the twisted angle, which varied from 60 to 270°, the number of twisted strip tentacles, which ranged from 4 to 10, and the width of the twisted strip tentacles, which spanned from 1 to 4 mm. This comprehensive approach allows for a thorough understanding of how these parameters influence the hydrothermal characteristics. The findings reveal that incorporating the conical twisted strip turbulator can significantly elevate heat transfer and pressure drop—by factors of up to 3.31 and 5.45, respectively—when compared to a plain tube design. The optimal performance enhancement criteria of 1.93 was achieved with a turbulator featuring a twisted angle of 180°, six twisted strip tentacles, and a strip width of 4 mm. Moreover, the results showed that heat transfer and pressure drop are directly related to the twisted angle, the number of twisted strip tentacles, and the width of the twisted strip. However, the performance enhancement criteria may improve or worsen as these parameters increase.