Numerical Analysis of Heat Transfer and Flow Field Due to Slot Air Jet Impingement for the Cases of Moving Plate and Moving Nozzle

Heat transfer to/from long flat surfaces is often accomplished by employing arrays of impinging air jets. Both cases of the moving target plate and the jet issuing device could be other options, which have been investigated numerically in the present study. Heat transfer distribution on a hot stationary flat plate impinged by a slot air jet was first specified. Air jet Reynolds number at the nozzle exit plane and the nozzle-to-plate separation were Re = 5000 and H/W = 5, respectively. The effect of movement of the target plate and the nozzle exit plane was then separately examined on both the flow and thermal fields. The distribution of the local Nusselt number was presented for a range of the moving nozzle and the moving plate velocities. There was a slight change in the flow and thermal fields predicted for the stationary case when the relative velocity was small. However, the flow field and the corresponding Nusselt number distribution diverged from the symmetrical distribution, being different for the two cases of the moving nozzle and the moving plate. The results indicated that the average Nusselt number decreased more dramatically in the case of moving nozzle.