Fluid Flow and Turbulent Convectional Heat Transfer Simulation in Twisted Elliptical Tube
نویسندگان
1 Faculty of Mechanical Engineering, Babol Noshirvani University of Technology, Babol, Iran
2 Department of Mechanical Engineering, National University of Skills, Tehran, Iran
3 Faculty of Mechanical Engineering, Babol Noshirvani University of Technology, Babol, Iran
doi
10.5829/ije.2025.38.06c.05چکیده
The Twisted Elliptical Tube (TET) is a promising heat exchanger (HEX) design that enhances heat transfer through the induction of secondary flows, albeit at the cost of increased pressure drop (PD). This numerical study investigates turbulent flow and heat transfer characteristics within TETs across a Reynolds number range of 8,000–20,000, employing the k-ω SST turbulence model for simulation. The research focuses on evaluating the impact of key geometric parameters, including aspect ratio, uniform twist length, reverse twist direction, and non-uniform twist length. The results demonstrate that decreasing the twist length (increasing the number of turns) and increasing the aspect ratio (flattening the tube geometry) lead to significant improvements in heat transfer and PD. Furthermore, reversing the twist direction at specific sections enhances mixing and thermal performance compared to TETs with uniform twist directions. Among the configurations studied, a TET with a non-uniform twist length arrangement transitioning from low to high twist lengths (e.g., 100-200-400 mm) exhibited the highest Performance Evaluation Criterion (PEC). This design optimally balances heat transfer enhancement (THE) with reduced PD, making it particularly suitable for high-efficiency applications. The findings provide valuable insights into the potential of TETs for improving HEX performance and highlight the importance of geometric optimization for achieving superior thermal and hydraulic performance in industrial applications.
