Heat Transfer Characteristics of Trapezoidal Duct using Delta Wing Vortex Generators

This study experimentally examined the impact of delta wing Vortex Generators (VGs) on heat transfer within a trapezoidal duct using airflow. VGs were installed at varying angles of attack (β). Results revealed a significant enhancement in heat transfer coefficients compared to a smooth duct. The Nusselt Number (NU) consistently increased with Reynolds number (Re) for all configurations. However, a key finding was that VGs significantly increased Nu, even at identical mass flow rates, demonstrating the crucial role of vortex-induced turbulence in augmenting heat transfer. The ratio of Nu with VGs to that without (Nu/Nuo) increased with increasing Re. Notably, the highest Nu/Nuo values were observed at β = 300. Comparing experimental data to theoretical predictions showed a considerably higher Nu/NuD ratio at β = 300. Furthermore, the Stanton Number (St) and Thermal Performance Enhancement Factor (TEF) exhibited substantial improvements with VGs, with the highest values recorded at β = 300. These findings strongly suggest that strategically placed VGs can effectively enhance heat transfer within trapezoidal ducts, providing valuable insights for optimizing thermal performance in various engineering applications. Major Findings: This study demonstrated that incorporating delta wing Vortex Generators (VGs) significantly enhanced heat transfer within a trapezoidal duct compared to a smooth duct. The Nusselt number (Nu) increased with Reynolds Number (Re), and the presence of VGs further augmented Nu, even at constant mass flow rates, highlighting the crucial role of vortex-induced turbulence. The highest heat transfer enhancement was observed at a VG angle of attack (β) of 300 degrees.