轮缘曲线对低反力度跨声速高负荷转子性能影响的数值研究

Impact of Shroud Contouring on Performance of Low-Reaction Transonic Highly Loaded Rotor

关键词:  轮缘型线  低反动度  高负荷  跨声速转子  气动性能  压气机

Key words:  Shroud contouring  Low-reaction  High-load  Transonic rotor  Aerodynamic performance  Compressor

摘要:

为探索更优的轮缘子午造型方式，进一步优化低反力度转子性能，利用三维数值模拟，对两级低反动度高负荷对转压气机第一级风扇转子的三种不同轮缘造型进行了比较研究。结果表明，与直线轮缘型线相比，凸凹波浪型(正弦曲线)轮缘可提高通流能力，降低叶尖进口激波强度，但同时增加了叶根出口结尾激波强度，转子峰值效率降低0.37%，峰值压比下降;凹凸波浪型(正弦曲线关于直线的对称曲线)轮缘通流能力最低，尽管叶尖前缘激波强度增加，但近尾缘区域凹形造型使得根部出口结尾激波强度大幅降低，转子峰值效率提升了0.05%，峰值压比上升。需要指出的是，与直线型轮缘相比，采用波浪型轮缘型线的失速裕度均下降。合理的轮缘型线是在降低叶尖反力度和负荷，确保不发生附面层分离的前提下，可以有效降低叶尖前缘激波强度和叶根结尾激波强度，提升转子气动效率。

Abstract:

In order to explore a superior shroud profiling to further optimize the performance of the low-reaction rotor， three-dimensional numerical simulation is utilized to conduct a comparative study on three different shroud shapes from the first rotor in a two-stage low-reaction high-load counter-rotating compressor. The results show that compared to the case with straight line shroud， the concave-convex wave type (sinusoidal) shroud can improve the flow capacity and reduce the shock intensity of the tip， but at the same time increase the terminal shock intensity at outlet， the rotor peak efficiency decreased by 0.37% and the peak pressure ratio decreased. The convex-concave wave type (the symmetry curve of the sinusoidal curve with respect to the straight line) rotor has the lowest through-flow capacity. Despite an increase in the shock intensity at the leading edge of the blade tip， the concave part of the shroud near the trailing edge significantly reduces the terminal shock intensity at the exit， resulting an increase of 0.05% in rotor peak efficiency with increasing peak pressure ratio. It should be noted that， compared with the linear shroud， the use of wave-type shroud leads to a reduced stall margin. Appropriate shroud contouring could reduce the reaction and loading in the tip region. The shock strength at the leading edge of the blade tip and the trailing edge is effectively reduced to enhance the rotor aerodynamic efficiency in the context that no boundary layer separation occurs.