针对直升机机动飞行时操纵突变状态的复合材料旋翼桨叶非定常气动/弹性载荷计算，建立了一套适用于非定常机动飞行气弹载荷模拟的高精度CFD/CSD紧耦合分析方法，主要包括旋翼运动嵌套网格生成及弹性变形方法、基于可压缩雷诺平均N-S方程的非定常流场求解方法、基于中等变形梁理论和Hamilton原理建立的桨叶结构动力学模型和适用于旋翼桨叶机动飞行模拟的非定常CFD/CSD紧耦合策略。随后，采用具备先进外形的桨尖后掠直升机旋翼，开展了缩比模型旋翼机动状态下操纵突变风洞试验研究。在验证本文数值模拟方法有效性的同时，针对不同操纵速率、幅值对机动状态旋翼气动特性综合影响开展了详细分析，得到不同机动状态下旋翼操纵对旋翼气动载荷影响的一般规律。
To calculate the unsteady aerodynamic/elastic load of composite rotor blade in helicopter maneuvering flight, a set of high-precision CFD/CSD tight coupling method is established, mainly including overset grid generation and elastic deformation method for rotor motion, unsteady flowfield solution method based on compressible Reynolds-averaged N-S equation, structural dynamic model of rotor blade built based on moderate deformation beam theory and Hamilton principle, and unsteady CFD/CSD tight coupling strategy suitable for rotor blade maneuvering flight simulation. Subsequently, a wind tunnel experimental investigation on abrupt changes in rotor control input under maneuvering conditions was conducted using a scaled model rotor of a swept-tip helicopter with advanced configuration. While verifying the validity of the numerical simulation method in this paper, a detailed analysis is carried out on the comprehensive influence of different maneuvering rates and amplitudes on rotor aerodynamic characteristics under maneuvering conditions, and the general laws of the influence of rotor maneuvering on rotor aerodynamic loads under different maneuvering conditions are preliminarily obtained.
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