关键词: 航空发动机;涡轮叶片;气膜冷却;综合冷却效率;红外修正

Abstract: In order to study the integrated cooling efficiency of air-cooled turbine blade and its influencing factors， the infrared thermal imager was adopted for the measurement of blade surface temperature field， and 15 thermocouples were set up in the middle section of the turbine blades for calibration， obtaining accurate surface temperature field distribution. The influences of flow ratio， temperature ratio and pressure ratio on the blades integrated cooling efficiency were thus deduced. The experimental results show that the temperature field distribution of the blade is affected by both internal cooling and external surface heat transfer， with the leading edge and the tip part of blade at a higher temperature state. Under experimental conditions， the integrated cooling efficiency of the blade is effectively improved by increasing the flow ratio. With the flow ratio increases from 0.02 to 0.07， the arc-averaged integrated cooling efficiency rises from 0.426 to 0.645， which means a growth of 51.4%. Although the large temperature ratio can reduce the blade temperature，the temperature ratio is found having no obvious effect on the integrated cooling efficiency. When the pressure ratio increases from 1.3 to 1.5， the arc-averaged integrated cooling efficiency goes up from 0.524 to 0.565， resulting in a 7.8% growth.

Key words: Aero-engine;Turbine blade;Film cooling;Integrated cooling efficiency;Infrared calibration