主动扭转旋翼振动载荷减缓控制优化

Optimal active twist control for rotor vibration reduction

为降低旋翼前飞状态的桨毂振动载荷水平,应用主动扭转旋翼技术,开展最优控制方案研究。建立基于中等变形梁理论的旋翼气动弹性动力学模型,以预测稳态飞行的桨毂振动载荷。使用UH-60A直升机旋翼算例验证所建模型准确性并作为研究基准。通过谐波相位及幅值变参分析,研究单谐波扭转控制对振动载荷的影响。构建基于遗传算法的主动扭转旋翼控制参数优化框架,开展展向一致多谐波扭转控制参数优化与分段多谐波扭转控制方案优化。结果表明:优化的多谐波扭转控制相比单谐波主动扭转控制可起到更好的桨毂振动载荷减缓效果。而以桨叶中点为分段点的最优2段扭转控制方案,通过对内外段桨叶施加不同的扭转控制规律,进一步降低了六方向的振动载荷水平。

The active twist control rotor is investigated to evaluate the effectiveness in rotor vibration reduction.A numerical model for predicting the isolated rotor vibration loads in steady level flight is deployed and validated by modeling a UH-60A rotor.A parametric sweep of the amplitude and phase angle for uniform single-harmonic active twist control is conducted to demonstrate the effects on rotor vibration loads.The optimal control schedule of the uniform multi-harmonic twist control for vibration reduction are obtained using an optimization framework based on genetic algorithm.The results indicate that the uniform multi harmonic twist control reduces the rotor vibration loads more than the uniform single-harmonic active twist control.An optimal 2 segment twist control layout with the segment point at the midpoint of the blade achieves further rotor vibration reduction by applying divergent control schedules to each segment.