This is an unedited manuscript accepted for publication and provided as an Article in Press for early access at the author’s request. The article will undergo copyediting, typesetting, and galley proof review before final publication. Please be aware that errors may be identified during production that could affect the content. All legal disclaimers of the journal apply.
Pranjul Mishra,
Divyanshu Shukla,
Nikhil Bajpai,
Aman Singh,
- Student, Department of Mechanical Engineering, Bansal Institute of Engineering and Technology Affliated to A.P.J Abdul Kalam University, Lucknow, Uttar Pradesh, India
- Student, Department of Mechanical Engineering, Bansal Institute of Engineering and Technology Affliated to A.P.J Abdul Kalam University, Lucknow, Uttar Pradesh, India
- Assistant Professor, Department of Mechanical Engineering, Bansal Institute of Engineering and Technology Affliated to A.P.J Abdul Kalam University, Lucknow, Uttar Pradesh, India
- Student, Department of Mechanical Engineering, Bansal Institute of Engineering and Technology Affliated to A.P.J Abdul Kalam University, Lucknow, Uttar Pradesh, India
Abstract
This research focuses on the design and evaluation of a vortex flow generator (VFG) for improving heat transfer performance in a straight circular tube. Vortex generators create longitudinal and swirling secondary flows inside the tube, which enhance fluid mixing, disturb the thermal boundary layer, and increase convective heat transfer. Vortex flow generators placed inside straight tubes are widely used to improve heat transfer performance in thermal systems. These devices create swirling and longitudinal vortices that break the thermal boundary layer, increase fluid mixing, and enhance the rate of heat transfer. This review summarizes the recent developments in different types of vortex generators such as twisted strips, winglets, swirl inserts, and cone-shaped elements. These induced vortices break and thin the thermal boundary layer while facilitating aggressive fluid mixing between the cool central core flow and the hot wall region, thereby significantly increasing the local Nusselt number and overall convective heat transfer rate. Recent advancements highlight a shift toward hybrid techniques combining modified VFG geometries with nanofluids or active-passive integrations to achieve high thermal enhancement while mitigating pumping power losses. Standardized experimental frameworks and detailed computational fluid dynamics (CFD) modeling utilizing turbulence models remain vital for future optimization. Vortex flow generators significantly boost convective heat transfer (Nusselt number) by disrupting thermal boundary layers and improving fluid mixing. Standardized testing and detailed flow visualization are required to optimize future designs. This paper presents a comprehensive review of the design, fluid mechanics, and structural optimization of Vortex Flow Generators (VFGs) operating within straight circular tubes. The continuous innovation in convective heat transfer enhancement. In conventional smooth-tube heat exchangers, thermal performance is severely constrained by the development of a stagnant viscous and thermal boundary layer along the inner tube wall, creating significant thermal resistance.
Keywords: Straight tube, electric heater, vortex flow generator, Swirl wing, heat transfer, Heat transfer enhancement
References
- Guo ZY, Liu XB, Tao WQ, Shah RK. Effectiveness–thermal resistance method for heat exchanger design and analysis. Int J Heat Mass Transf. 2010;53(13-14):2877-2884. doi:10.1016/j.ijheatmasstransfer.2010.02.008.
- Aparesh, Datta A, Das PK, Dey P, Sanyal D. Multi-objective optimization of laminar heat transfer and friction factor in rectangular microchannel with rectangular vortex generators: an application of NSGA-II with gene expression programming metamodel. J Heat Transfer. 2017. doi:10.1115/1.4035890.
- Luo Y, Li G, Bennett NS, Luo Z, Munir A, Islam MS. Heat transfer enhancement in heat exchangers by longitudinal vortex generators: a review of numerical and experimental approaches. Energies. 2025;18(11):2896. doi:10.3390/en18112896.
- Du Y, Wongcharee K, Chuwattanakul V, Naphon P, Maruyama N, Hirota M, et al. Heat transfer intensification in a heat exchanger tube with continuous V-rib twisted tapes installed. Appl Sci. 2025;15(10):5612. doi:10.3390/app15105612.
- Zheng N, Zhang K, Chen Q, Sun Z. Novel self-join winglet vortex generators for enhanced heat transfer of turbulent airflow in round tubes. Int Commun Heat Mass Transf. 2022;130:105806. doi:10.1016/j.icheatmasstransfer.2021.105806.
- Dogan M, Erzincan S. Experimental investigation of thermal performance of novel type vortex generator in rectangular channel. Int Commun Heat Mass Transf. 2023;144:106785. doi:10.1016/j.icheatmasstransfer.2023.106785.
- Chithra VP, Jayakumar V, Bakthavatchalam B, Kusekar SK, Irshad K, Habib K. Thermal performance enhancement of laminar flow using compound twisted square duct and variable pitch twisted tape inserts. Case Stud Therm Eng. 2024;64:105462. doi:10.1016/j.csite.2024.105462.
- Ismail M, Ali AM, Costa Pereira SC. Vortex generators in heat sinks: design, optimisation, applications and future trends. Results Eng. 2025;25:104216. doi:10.1016/j.rineng.2025.104216.
- Kongkaitpaiboon V, Nanan K, Eiamsa-ard S. Experimental investigation of heat transfer and turbulent flow friction in a tube fitted with perforated conical-rings. Int Commun Heat Mass Transf. 2010;37(5):560-567. doi:10.1016/j.icheatmasstransfer.2009.12.015.
- Rathaur DK, Sarviya RM, Rajput SPS. Synergistic enhancement of heat transfer in tubular heat exchangers using twisted tape inserts and nanofluids: an integrated numerical and experimental review. Int J Heat Fluid Flow. 2026;118:110180. doi:10.1016/j.ijheatfluidflow.2025.110180.
Trends in Mechanical Engineering & Technology
| Volume | 16 | |
| 03 | ||
| Received | 17/07/2026 | |
| Accepted | 14/09/2026 | |
| Published | 06/10/2026 | |
| Publication Time | 81 Days |