跨声速串列转子气动耦合机制分析及优化设计

Transonic Tandem Rotor Aerodynamic Coupling Mechanism and Its Optimization

关键词:  高负荷风扇  跨声速串列转子  气动耦合  激波结构  数值模拟

Key words:  High loaded fan  Transonic tandem rotor  Aerodynamic coupling  Shock wave structure  Numerical simulation

摘要:

串列叶片可以突破常规压气机气动负荷的限制，具有良好的工程应用前景。但跨声速串列转子通道内激波系结构复杂，控制难度较大，导致气动效率偏低。为解决上述问题，利用数值模拟的方法对比了串列转子前排在串列和单转子条件下气动参数、流场的变化规律，分析了跨声速串列转子前/后排气动耦合机理，并完成了优化设计。结果表明：（1）串列条件下，前排落后角、总压比沿叶高分布规律发生变化，槽道正激波显著增强，是导致跨声速串列转子效率水平低下的根本原因；（2）针对跨声速串列叶型的优化可以实现流场的定制设计，优化后前/后排匹配工作状态及激波结构显著改善；（3）优化后的串列转子失速裕度提升约6%、设计点等熵效率提升约1.5%，证明了本文提出的优化设计思路及方法的有效性。

Abstract:

Tandem blade technology has become an effective method to break the load limit of conventional compressor aerodynamic configurations. It is difficult to control the complicated shock wave structure in transonic tandem blade， so the aerodynamic efficiency maintains at lower level. To solve the above tough problem， the forward blade aerodynamic parameters and flow fields were compared in tandem and single-blade configurations by using CFD method. Based on this study， the aerodynamic coupling mechanism between forward and aft blade of transonic tandem rotor was analysed， and the optimization was conducted. The CFD results show that： （1） In tandem configuration， the radial distributions of forward blade deviation and total pressure ratio get changed， and the passage shock wave enhances， which cause the difficulty for improving the tandem rotor efficiency. （2） The flow field can be redesigned by optimizing transonic tandem air-foil， as a result， the shock wave and matching characteristic between forward and aft blade can be improved. （3） Compared to the original tandem rotor， the optimization scheme stall margin increases by 6%， and the isentropic efficiency at design point increases by 1.5%， which proves the feasibility and validity of optimizing principle put forward in this paper.