盖板式预旋系统温降特性的实验研究

Experimental Investigation on the Temperature Drop of a Cover-plate Pre-swirl System

预旋供气系统是为发动机涡轮转子叶片提供合适压力、温度和流量冷却气流的部件系统,因其具有显著降低冷气相对总温的巨大潜力而受到关注。本文在系统压比1.10~1.50、涡轮盘转速3000~9720 r/min参数范围内,通过在转盘上测量气流相对总温来获得预旋系统的温降特性,并通过一系列温度校准实验来确保转盘气流温度测量的准确性。分析了转速,压比和喷嘴出口旋转比对系统温降特性的影响。研究结果表明:随着转速的升高,预旋系统温降先小幅增大,之后迅速减小,最大可达7.6 K;随着压比的增大,系统温降增大;系统无量纲温降随喷嘴出口旋转比近似呈线性变化。

The pre-swirl air delivery system is a component system for providing cooling air with suitable pressure,temperature and mass flow rate to the aeroengine turbine blades,which receives wide attentions because of its significant potential of reduction in the relative total temperature of the cooling air.Experiments on the temperature drop characteristics of a cover-plate pre-swirl system were carried out at pressure ratio range 1.10~1.50,and turbine disc rotating speed range3000~9720 r/min.Besides,a series of temperature calibration experiments were carried out to ensure the accuracy of the measurement on the temperature of the airflow on the rotating disk.The effects of rotating speed,pressure ratio and nozzle outlet swirl ratio on the temperature drop of the pre-swirl system were analyzed.The experimental results show that:the temperature drop of the pre-swirl system increases slightly,and then decreases rapidly with the increase of the rotating speed,which reaches a maximum of 7.6 K.Besides,the temperature drop rises with increasing the system pressure ratio.The dimensionless temperature drop varies approximately linearly with the nozzle outlet swirl ratio.