ZHU Hua, YAN Biao, LIU Yusong, et al. Influences of Blowing Ratio and Humidity Ratio of Moist Air on Flow and Heat Transfer Characteristics of Film Cooling of a Flat Plate[J]. 2022, 56(6): 151-163.
DOI:
ZHU Hua, YAN Biao, LIU Yusong, et al. Influences of Blowing Ratio and Humidity Ratio of Moist Air on Flow and Heat Transfer Characteristics of Film Cooling of a Flat Plate[J]. 2022, 56(6): 151-163.DOI: 10.7652/xjtuxb202206018.
Influences of Blowing Ratio and Humidity Ratio of Moist Air on Flow and Heat Transfer Characteristics of Film Cooling of a Flat Plate
To investigate the difference of the cooling characteristics of film cooling when moist air and dry air are used as cooling medium respectively
the experimental and numerical studies are carried and the effects of blowing ratio and humidity ratio of moist air on the film cooling performance of a flat plate are analyzed in detail. In the experimental test
the infrared camera was used to measure the temperature of the target surface. The effects of different blowing ratios and humidity ratios on the film-cooling performance were taken into consideration and the variation of film cooling efficiency with respect to blowing ratio and humidity ratio was obtained. In the numerical analysis
a film cooling model with a single film-cooling hole with periodical boundary conditions was established
and the commercial software ANSYS CFX is used to investigate the influences of the blowing ratio and the humidity ratio on film cooling performance under high temperature and high pressure condition. The experimental results show that when the blowing ratio is 0.7
the cooling performance of film cooling of the target surface improves with the increasing humidity ratio
and when the humidity is 188.9 g/kg
the average cooling efficiency of the whole target surface improves 4.8% compared to dry air cooling. The numerical study results are consistent with the experimental results. The results also show that when the blowing ratio is 0.7
the cooling performance of film cooling is optimal
and the cooling performance of film cooling of the target surface improves with the increasing humidity ratio when the blowing ratio is between 0.3 and 0.7
while the film-cooling efficiency shows a reverse trend when blowing ratio is higher than 0.7. Based on the experimental and numerical results
a correlation of film-cooling performance of the target surface in terms of the blowing ratio and the humidity ratio was proposed. The correlation has a relative error within ±2%.
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