Experiment on film cooling characteristics for longitudinal corrugated heat-shield

Detailed experimental study on film cooling effect of one afterburner longitudinal corrugated heat-shield was carried out. The surface temperature distribution of the heat-shield was captured by an infrared thermal imaging camera. The influence of adiabatic cooling efficiency was analyzed by different plate types, blow ratios and perforated percentages. In the experiment, flat panel and longitudinal corrugated heat-shield were adopted; the range of blow ratio was 0.5-3.0; the perforated percentage was 1.4%-3.7%. Results showed that, the film cooling efficiency of longitudinal corrugated heat-shield fluctuated with the fluctuation of corrugated plate structure and became larger than that of flat panel, while the film cooling efficiency of flat panel increased gradually along the way; with the increase of blow ratio, the film cooling efficiency increased gradually and reached to the maximum when the blow ratio increased to 3.0; the film cooling efficiency on the valley of the longitudinal corrugated surface was relatively higher than that on the wavy peak; the smaller the blow ratio, the more obvious the change of the film cooling efficiency with the fluctuation of corrugated plate; the film cooling efficiency changed and increased slowly along the high blow ratio (blow ratio of 2.0-3.0). As a whole, the film cooling efficiency increased gradually with the increase of the perforated percentage, and the film cooling efficiency at small perforated percentage (perforated percentage of 1.4%, 2.7%) was not much different, but on the leeward side of secondary flow, the film cooling with large perforated percentage was high.