ISSN Online: 2377-424X
ISBN Print: 1-56032-797-9
International Heat Transfer Conference 11
Heat Transfer Measurements from a Flat Plate to a Swirling Impinging Jet
摘要
Local heat transfer coefficients from a flat plate to a swirling, circular air impinging jet were measured experimentally. A well controlled swirling, circular air impinging jet at room temperature was created by a specially designed swirl generator. The experimental method used in this investigation was the transient liquid-crystal technique. During the experiments, the surface liquid-crystal color distribution of the test plate was recorded using a video imaging acquisition system and the color information was translated into surface temperature distribution through a digital color image processing unit. Local heat transfer coefficients were obtained using a surface transient heat conduction analysis. The flow Reynolds numbers of the jet was kept at 23,000. The swirl number, S, and the jet-to-plate distance, L/D, were varied parametrically in the experiments. Detailed radial heat transfer distributions on the surface for S = 0, 0.21, 0.35, and 0.47 and for jet-to-plate distances, L/D, of l to 12 were analyzed. The effect of swirl number on heat transfer distribution was analyzed by comparing to data obtained from a single non-swirl jet with similar flow configurations.