Numerical Investigation of Axisymmetric Jet Impingement Heat Transfer on a Flat Plate Equipped with Vortex Generator

This study investigates heat transfer enhancement between a turbulent air jet and a flat wall using an axisymmetric vortex generator in the form of a tab. The number of Reynolds ranged 10,000 to 50,000, and the spacing between the jet nozzle and the impingement surface ranged from 0.5 D to 6 D. The vortex generator influence on heat transfer was simulated by adjusting its height e (0.5 < e/delta < 2) and location L (0.25 < L/D < 2). The SST k-omega model was used, validated against relevant experimental data. The local heat transfer distributions on the target surface were studied, with a particular focus on the vortex generator region. The findings indicated the presence of a recirculation zone behind the tab, which is responsible for enhancing heat transfer. when the tab is set at a height matching the boundary layer thickness and positioned at 0.7 D from the axis, the maximum improvement in PEC and the average Nusselt number Nu is achieved, reaching 3.8%. Additionally, Correlations were proposed for calculating average Nu based on the Re and geometric parameters (H, e and L).