摘要
分别对常规叶栅、下端壁上凸和下端壁下凹叶栅的流场进行了详尽的数值模拟,通过将下端壁上凸和下端壁下凹叶栅中的通道涡的发生、发展过程与常规叶栅进行对比分析,对非轴对称端壁造型减小涡轮叶栅二次流损失的机理进行了初步的探讨。结果表明:下端壁上凸叶栅出口处的总压损失比常规叶栅下降了4.2%,下端壁下凹叶栅出口处的总压损失比常规叶栅增加了11.9%;在下端壁上凸叶栅中,下通道涡的形成比常规叶栅和下端壁下凹叶栅滞后,失去了充分发展的"机会"。这是非轴对称端壁造型能够减小涡轮叶栅二次流损失的根本原因。
Numerical simulation has been carried out to obtain detailed flow structure in conventional turbine cascade and two kinds of turbine cascade with non-axisymmetric endwall. Comparison and analysis of development process of passage vortex in three kinds of turbine cascade have been performed to find out how non-axisymmetric endwall profiling affect secondary flow in turbine cascade. Investigation result shows ：When lower endwall of turbine cascade protrudes upward, total pressure loss at exit of cascade decreases 4.2% than conventional turbine cascade; When lower endwall of turbine cascade protrudes downward, total pressure loss at exit of cascade increases 11.9% than conventional turbine cascade. When lower endwall of turbine cascade protrudes upward, compared with conventional cascade and cascade with lower endwall protruded downward, formation of lower passage vortex is ＂later＂ , so less ＂opportunity＂ is acquired to grow fully. This is the key point which makes non-axisymmetric endwall profiling work effectively.
出处
《推进技术》
EI
CAS
CSCD
北大核心
2008年第3期355-359,共5页
Journal of Propulsion Technology
关键词
涡流
二次流
非轴对称端壁造型^+
Vortex flow
Secondary flow
Non-axisymmetric endwall profiling ^＋
