风扇转子叶片防颤振设计技术

以某两级风扇为对象开展防颤振设计技术研究。风扇转子叶片设计中，选择了合适的展弦比，既考虑到气动性能水平，还考虑到结构质量和颤振稳定性。采用流固耦合能量法评估所设计风扇的各排转子叶片的颤振稳定性问题，并通过叶片厚度、三维造型、根尖弦长比等设计参数的调整消除颤振风险。研究结果表明:展弦比不应是方案设计阶段防颤设计唯一的关注参数；在叶尖跨声速的转速更容易发生颤振现象；较强的叶尖前缘激波会造成较强的流固耦合作用，形成复杂的气动功分布结构；叶片厚度和尖根弦长比等参数是改善叶片颤振风险的有效参数。 

Fan rotor blade flutter free design technology

Flutter free design technology of a two stages fan was investigated. During fan rotor blades design, appropriate aspect ratio was selected by considering aerodynamic performance, weight and flutter stability. Energy method was used to analyze the flutter stability for both rotor blades of the fan. Blade thickness, three dimensional blade shape and tip to hub chord ratio were modified to eliminate the flutter risk. The investigation showed that the aspect ratio was not the only parameter of concern for flutter free design in conceptual design phase. The near stall points at the rotational speed when blade tip flow was transonic were more prone to flutter. Strong shock waves could enhance the coupling effect between fluid and structure, and induce complex construction of aerodynamic work distribution. Blade thickness and tip to hub chord ratio were effective parameters to improve flutter risk.