抄録
As a method of passive heat transfer augmentation in a two-dimensional impinging jet, the use of transverse-repeated surface roughness of square cross-section has been proposed by the present authors [Ref.8].The overall heat transfer rate of rough impingement wall can be by two times larger than that of flat wall. In order to supplement the know-legde about the mechanism of heat transfer augmentation, the flow structure in the stagnation region is visually studied by using the smokewire technique. The large-scale vortex-like structure-observed on the flat wall is also confirmed on the rough wall. From the analysis of the photographic records, it is concluded that the augmentation should be due to the effect of the stretching of large-scale vortex combined with the flow separation and reattachment.
