Advancements in Heat Transfer Enhancement using Perforated Twisted Tapes: A Comprehensive Review

Improved heat transfer is crucial for better heat exchanger performance in many industries, from power plants to spacecraft. These methods facilitate improved energy utilisation, reduced operational expenses, and more compact system configurations, underscoring their critical role in ongoing research and development efforts. Typically classified into passive, active, and compound categories, these techniques cater to different needs: passive methods, devoid of external power requirements, are favoured for their simplicity, reliability, and cost-effectiveness. In contrast, active techniques harness external energy inputs to augment performance, while compound methods integrate advantages from both passive and active approaches to achieve synergistic outcomes. This review critically examines passive heat transfer enhancement techniques, highlighting recent advancements and their practical implementations across thermal systems. Key emphasis is placed on strategies like twisted tape inserts, perforated surfaces, and vortex generators, which disrupt boundary layers, induce turbulence, and enhance swirl flows to elevate convective heat transfer coefficients and optimise thermal performance without compromising system efficiency. Major Findings: The study highlights that perforated twisted tape inserts play a significant role in enhancing convective heat transfer by generating swirl flows, increasing turbulence, and reducing the thermal boundary layer thickness. Various geometrical modifications, such as rectangular-winged, alternate-axis, and dual twisted tapes, have demonstrated remarkable improvements in heat transfer performance, with enhancement rates reaching up to 219%, albeit with an associated increase in pressure drop. Overall, the review confirms that passive heat transfer enhancement methods, particularly optimised twisted tape designs, offer an energy-efficient and cost-effective solution for improving the thermal performance of heat exchangers across industrial applications.