The objective of this work is to computationally investigate the impact of an incidence-tolerant rotor blade concept on gas turbine engine performance under off-design conditions. When a gas turbine operates at an off-design condition such as hover flight or takeoff, large-scale flow separation can occur around turbine blades, which causes performance degradation, excessive noise, and critical loss of operability. To alleviate this shortcoming, a novel concept which articulates the rotating turbine blades simultaneous with the stator vanes is explored. We use a finite-element-based moving-domain computational fluid dynamics (CFD) framework to model a single high-pressure turbine stage. The rotor speeds investigated range from 100% down to 50% of the designed condition of 44,700 rpm. This study explores the limits of rotor blade articulation angles and determines the maximal performance benefits in terms of turbine output power and adiabatic efficiency. The results show articulating rotor blades can achieve an efficiency gain of 10% at off-design conditions thereby providing critical leap-ahead design capabilities for the U.S. Army Future Vertical Lift (FVL) program.

中文翻译：

---

非设计条件下自适应燃气轮机定子-转子流动相互作用的高保真有限元建模和分析

这项工作的目的是通过计算研究在非设计条件下，容错转子叶片概念对燃气涡轮发动机性能的影响。当燃气轮机在悬停飞行或起飞等非设计条件下运行时，涡轮叶片周围会发生大规模的流动分离，这会导致性能下降、噪音过大和可操作性的严重损失。为了减轻这个缺点，探索了一种新颖的概念，该概念将旋转的涡轮叶片与定子叶片同时进行铰接。 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 我们使用基于有限元的移动域计算流体动力学 (CFD) 框架来模拟单个高压涡轮级。所研究的转子速度范围为设计条件 44,700 rpm 的 100% 至 50%。本研究探讨了转子叶片铰接角度的限制，并确定了涡轮机输出功率和绝热效率方面的最大性能优势。结果表明，铰接式转子叶片可以在非设计条件下实现 10% 的效率增益，从而为美国陆军未来垂直升降 (FVL) 计划提供关键的超前设计能力。