ISSN Online: 2377-424X
ISBN Print: 0-89116-559-2
International Heat Transfer Conference 8
FULL COVERAGE IMPINGEMENT HEAT TRANSFER: THE INFLUENCE OF CHANNEL HEIGHT
要約
Square arrays of circular jets, with an X/D of 7.1, impinging on an electrically heated continuous metal target plate were investigated for 0.5 < Z/D < 9.5 with a single side exit from the impingement gap. Crossflow produced a reduction in the impingement heat transfer at large Z/D but an enhancement of heat transfer with small Z/D. It was shown that this latter effect was mainly due to flow maldistribution caused by pressure gradients within the gap. A simple procedure was developed to predict when this effect was significant. For turbine blade impingement cooling designs, it was shown that flow maldistribution should not be a problem. The influence of crossflow heat transfer at small Z was also a significant contribution to the higher heat transfer.