Convective heat transfer enhancement between dual impinging jets through vibrating piezo-fan integration

This study investigates the enhancement and uniformity of heat transfer in multi-jet impingement systems through piezo-fan excitation. The primary objective is to analyze the fluid dynamics and heat transfer performance under varying jet-to-target distance (L/d), jet-to-jet distance (s/d), jet Reynolds number (Re_j), and piezo-fan configurations. Unsteady numerical simulations and experiments reveal that the longitudinal piezo-fan configuration significantly enhances heat transfer at secondary stagnation points, achieving a 37.5% increase in the overall heat transfer enhancement factor (χ) and a 20.7% improvement in heat transfer uniformity (ξ) at Re_j = 3500, L/d = 6, and s/d = 6. As L/d increases, the fan’s contribution becomes more pronounced, dominating the local heat transfer when the jet impingement weakens. The enhancement effect is most effective in laminar or transitional regimes, with χ and ξ decreasing sharply beyond Re_j = 5000. These findings highlight the potential of piezo-fan integration in optimizing multi-jet impingement systems for improved and more uniform convective heat transfer.