高压涡轮主动间隙热控制系统机匣传热特性试验

设计了实际尺寸高压涡轮（HPT）主动间隙控制（ACC）系统机匣组件试验件,模拟ACC系统在高温、高压条件下的工作状态,研究了HPT机匣的温度分布规律,以及机匣温度随冷气雷诺数的响应特性,验证了供气总管及冲击冷却管的流动特性。结果显示:供气总管压力分布均匀,冲击冷却管从进气端至封闭末端的沿程压力逐渐升高,但管内压力随冲击冷却管开孔面积比的增大而接近一致；当ACC系统不工作和工作时,机匣周向单点温度与平均温度最大相对偏差分别为48%和58%；而在ACC系统工作时,随冷气雷诺数的变大,涡轮外机匣温度能显著降低,试验工况中,机匣各冷却部位平均温度的降幅可达16%～37%,达到预期效果。基于试验测试数据,验证并改进了HPT机匣组件换热分析模型,该模型具有较高精度和良好适用性。 

Test on heat transfer characteristics of high pressure turbine casing with active clearance control system

Casing test specimen for high pressure turbine（HPT）active clearance control（ACC) system of trim size was designed. Operation of active clearance control system was simulated under high temperature and high pressure to verify the flow characteristics of cooling collector and impingement cooling pipes, and investigate the temperature distribution rules of HPT casing as well as responsive characteristics of casing temperature to cooling airflow. Results showed that the pressure distribution of air supply manifold was very even; for impingement cooling pipes, the pressure rose gradually from inlet to the end, but the pressure became consistent as the area of orifice on the pipe increased; the maximum relative deviation of circumferential temperature distribution of casing were 48% and 58%, for non operating and operating ACC system; when the ACC system was working, the temperature for turbine outer casing obviously decreased as cooling airflow increased; during the test, the average temperature for cooled parts on the casing decreased as much as 16%－37% up to expectation. Based on the test data, heat transfer model of HPT casing was validated and modified to be more precise and applicable.