冷气对多级涡轮翘曲S1流面优化的影响

Effects of Coolant on Twisted S1 Stream Surface Optimization in Multi-Stage Turbine

关键词:  气膜冷气  尾缘冷气  端壁冷气  翘曲流面优化  多级涡轮  可靠性  有效性

Key words:  Film cooling air  Trailing edge coolant  Endwall coolant  Twisted stream surface optimization  Multi-stage turbine  Validity  Reliability

摘要:

设计以翘曲S1流面优化为核心的多级涡轮气动优化流程，研究气膜冷气、尾缘冷气、端壁冷气对优化可靠性和有效性的影响。该流程能够对多种叶高处带叶片冷气的多级翘曲S1流面进行并行优化，提高了优化的可靠性。对两级高压涡轮给定三种叶片冷气方案:包括气膜冷气和尾缘冷气的叶身冷气、气膜冷气、无叶片冷气，分别进行翘曲S1流面优化设计。优化后翘曲S1流面平均气动效率分别提高0.20%、0.38%、0.07%，涡轮气动效率分别提高0.33%、0.32%、0.26%，优化的可靠性较好。分析可知，气膜冷气增强了径向二次流动，降低了优化的有效性，尾缘冷气则部分削弱了气膜冷气的消极作用；下端壁冷气较上端壁冷气对端区二次流的作用强，因此前者对翘曲S1流面优化的积极作用更好。

Abstract:

Multi-stage turbine aerodynamics optimization process was designed with the core of twisted S1 stream surface optimization，and the effects of film cooling air，trailing edge coolant，endwall coolant were researched on validity and reliability of the twisted S1 stream surface optimization. This process could advance parallel optimization for multi-stage twisted S1 stream surface with blade coolant in variety of blade height，which can improve twisted S1 stream surface optimization reliability. There were three blade coolant plans for a two-stage high pressure turbine: blade body coolant including of film cooling air and trailing edge coolant，film cooling air，without blade coolant，and the design of twisted S1 stream surface optimization was conducted. The average aerodynamic efficiency of twisted S1 stream surface increased by 0.20%，0.38%，0.07% and turbine aerodynamics efficiency increased by 0.34%，0.32%，0.28%，respectively. The optimization reliability was good. After analysis it is concluded that，film cooling air enhances radial secondary flow and then decreases the optimization validity，while trailing edge coolant weakens the negative effect of film cooling air partially. The bottom endwall coolant has more effect on secondary flow near endwall region than top endwall coolant，so the former plays a better positive role on S1 stream surface optimization.