A Numerical Study on Heat Transfer in Laminar Pulsed Slot Jets Impinging on a Surface

Numerical simulations are performed for laminar continuous and pulsed jets impinging on a surface in order to investigate the effects of pulsing frequency on the heat transfer characteristics. The time-averaged Nusselt number of pulsed jets is larger in the impinging jet region as compared to the continuous jet, while it is smaller in the outer wall jet region. At the stagnation point, the mean and RMS Nusselt numbers become larger and smaller, respectively, as the pulsing frequency increases. Unsteady behaviors of vortical fluid motions and temperature field are also investigated to understand the underlying mechanisms of heat transfer enhancement.

Authors:

• D. Kim

Keywords:

• Pulsed slot jet
• impingement
• pulsing frequency
• heat transfer enhancement.

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