高温风洞中空冷涡轮叶片冷却特性的实验研究

Experimental Investigation of Cooling Performance of Air-Cooled Turbine Blade in a High-Temperature Wind Tunnel

关键词:  燃气轮机  涡轮叶片  冷却效率  相对温度

Key words:  Gas turbine  Turbine blade  Cooling efficiency  Relative temperature

摘要:

为了研究涡轮叶片在高温燃气冲刷下的冷却特性，搭建了高温风洞环形叶栅实验台。采用红外热像仪对不同冷气流量比(0.016 ~ 0.036)及温比(0.47 ~ 0.58)工况下涡轮叶片吸力面冷却效率及温比特性进行了研究。结果表明:受叶片前后部冷却腔冷却特性的影响，吸力面前部和后部区域表现出了不同的冷却特性；在实验工况内，流量比从0.016增加到0.036过程中，叶片吸力面前、后部面积平均冷却效率分别增加了 30.4%和49.1%，相对温度分别降低0.017和0.049；当流量比不变，温比从0.47增加到0.58时，叶片吸力面前、后部面积平均冷却效率变化较小，分别减少了 2.9%和9.6%，相对温度分别增加0.013和0.015。

Abstract:

In order to investigate the cooling performance of a turbine blade scoured by high-temperature gas flow，an annular cascade test rig was set up. The distribution of temperature on suction side of blade was measured by an infrared camera. Effects of mass flow ratio (0.016 ~ 0.036) and temperature ratio (0.47 ~ 0.58) on cooling performance of blade were studied. Results showed that due to the influence of different cooling performance owned by the front and rear cooling chambers，the front and rear parts of the suction side of blade show different cooling performance. In the experiment，the area-averaged cooling efficiencies of the front and rear parts of suction side of blade increase by 30.4% and 49.1% with mass flow ratio increasing from 0.016 to 0.036，respectively. In the same process，the relative temeprature of the two parts decreases by 0.017 and 0.049，respectively. In case of the temperature ratio increasing from 0.47 to 0.58 with the mass flow ratio unchanged，the cooling efficiencies of the front and rear parts of suction side of blade both have minor changes，they decrease by 2.9% and 9.6%，respectively. However，the relative temperature of the two parts increases by 0.013 and 0.015，respectively， in the same process.