涡轮叶片最小冷气需求量的一种估算方法

A Method for Predicting Minimal Turbine Blade Cooling Air Requirement

通过涡轮叶片内外表面对流换热与固体导热的耦合计算,建立叶片冷气流量与叶片壁面温度分布之间的关系,从而获得涡轮叶片最小冷气需求量。首先根据假定冷气流量进行耦合计算叶片温度分布,并从中获得叶片温度峰值;再依据这一温度峰值,逐步调整冷气进口流量,直到叶片温度场符合设计要求。计算得出叶片最小冷气量为燃气总量的4.43%,叶片最高温度为1 299.11K。结果表明采用本文的方法估算的燃气涡轮叶片的冷却空气量是合理的。

To obtain the minimal turbine blade cooling air requirement, the relationship between the mass flow of cooling air and the temperature field of turbine blade is built, by the coupling calculation between heat convection and solid heat conduction for inside and outside surface of turbine blade. According to the assumed mass flow of cooling air, blade temperature distribution is acquired by coupling calculation to find the peak temperature of the blade. The peak temperature is used to adjust the cooling air mass flow of the blade until the temperature field satisfies the designing object. The minimal cooling air is 4.43% of the total gas, and the maximum temperature of the blade is 1299. 11K. The result shows that the method can estimate the turbine cooling air flow reasonably.