Influences of Inlet Reynolds Number and Humidity Ratio of Moist Air on Flow and Heat Transfer Characteristics of Impingement Cooling

被引：0
|
作者：
Li J. [1 ]
Fu Y. [1 ]
Zhang Z. [1 ]
Liao G. [1 ]
Li L. [1 ]
机构：
[1] Institute of Turbomachinery, Xi'an Jiaotong University, Xi'an
来源：
Hsi-An Chiao Tung Ta Hsueh/Journal of Xi'an Jiaotong University | 2020年 / 54卷 / 05期
关键词：
Gas turbine; Humidity ratio; Impingement cooling; Moist air; Reynolds number;
D O I：
10.7652/xjtuxb202005022
中图分类号：
学科分类号：
摘要：
To investigate the cooling of the blade leading edge of a humidified gas turbine, the effects of inlet Reynolds number and humidity ratio of moist air on the impingement cooling of flow and heat transfer are analyzed. An impingement cooling model with an inlet chamber, a row of circular impingement holes and an impingement cooling chamber is established. The ANSYS CFX software is used to numerically investigate the influences of inlet Reynolds number and humidity ratio of moist air on flow and heat transfer characteristics of impingement cooling, and the properties of the flow and heat transfer are summarized. Following the numerical results, the Nusselt number is correlated with the Reynolds number of impingement holes and the Prandtl number to obtain the heat transfer correlation of the moist air impingement cooling. The results show that the cooling performance of impingement cooling improves with the increasing Reynolds number and humidity ratio. After the impingement jet impacts the target surface, the coolant flows along the wall surface and forms a complex vortex structure in the impingement cooling chamber. When the inlet Reynolds number increases, the heat transfer of the target surface is enhanced due to an increasing coolant vorticity. The Nu distributions of the target surface for dry air cooling and moist air cooling have little differences with the same inlet Reynolds number, but the value of Nu for moist air cooling is slightly higher than that for dry air cooling and the difference increase with the increasing inlet Reynolds number. The coolant mass flow decreases with the increasing humidity ratio, while the Nu of the target surface increases with the increasing humidity ratio. The heat transfer correlation coincides well with the numerical results and can be used to predict the heat transfer coefficient of moist air impingement cooling. © 2020, Editorial Office of Journal of Xi'an Jiaotong University. All right reserved.
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页码：170 / 178
页数：8
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