柔性变形后缘以无缝、光滑的气动外形不仅在气动方面相比传统铰链舵面有显著优势，在提升噪声性能方面也具有较大潜力。在大涡模拟模型和基于Lighthill声比拟方法的FW-H方程基础上，利用CFD数值仿真研究了有缝后缘和无缝后缘的气动噪声特性对比。更进一步，在遭遇阵风时，通过无缝后缘柔性动态变形进行载荷减缓，并与无缝后缘刚性偏转进行载荷减缓效率和气动噪声特性对比。研究表明，在4°迎角下，无缝后缘相比有缝后缘纯音噪声峰值降低20.2dB；在4°-20°等效迎角的正弦阵风下，基于无缝柔性变形后缘的翼型载荷减缓效率均在60%以上，比刚性偏转后缘的载荷减缓效率高出10%-30%；且在12°等效迎角的正弦阵风下，无缝后缘柔性变形纯音噪声峰值相比刚性偏转最高可降低7.2dB。最后从动态特性和流场演化角度分析了无缝后缘两种偏转方式对阵风载荷减缓效率和气动噪声特性的影响机理。
The flexible morphing trailing edge's seamless and smooth aerodynamic shape not only offers significant improvements over traditional hinged rudders in aerodynamic performance but also has the potential to enhance noise reduction capabil-ities. Using large eddy simulation model and acoustic analogy method based on the FW-H equation, the aeroacoustic characteristics of the stitched and seamless trailing edges are investigated through CFD numerical simulation. Further-more, the study explores the aircraft's aeroacoustic characteristics when encounters gusts, with a particular focus on the flexible morphing of the seamless trailing edge. And load alleviation efficiency and aeroacoustic characteristics are com-pared with seamless trailing edge rigid deflection. The results show that at 4° Angle, the tonal noise peak of seamless trail-ing edge decreases by 20.2dB compared with that of slotted trailing edge. What's more, under the sine wind gust of 4°-20° equivalent Angle, the load alleviation efficiency of flexible morphing trailing edge is more than 60%, which is 10%-30% higher than the rigid deflection. In addition, the tonal noise peak value of flexible morphing trailing edge can be re-duced by 7.2dB compared with rigid deflection at 12° equivalent Angle sine gust. Finally, the effects of the two deflection modes of the seamless trailing edge on wind load alleviation efficiency and aeroacoustic characteristics are analyzed from the perspective of dynamic characteristics and flow evolution.
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