摘要
基于计算流体动力学(CFD)方法和噪声求解的FW-H(Ffowcs Williams-Hawkings)方程计算分析了共轴刚性旋翼在悬停状态下的气动噪声,并开展了气动干扰对噪声特性影响分析。结果表明:在悬停状态下,对于上下各四片桨叶的共轴刚性旋翼,桨叶表面压力随着桨叶旋转呈周期性变化,旋转一周出现8个小周期;声源的周期性变化导致在旋翼桨盘平面内,不同方向上的观测点的声压产生的“叠加效应”不一致,上、下旋翼桨叶交汇处的噪声水平要高于其他方位角;由于载荷的时变性导致在旋转轴方向上仍有明显的辐射噪声,在该方向上的噪声声压级明显要比单旋翼大得多。随着旋翼间距增大,双旋翼之间的干扰减小,桨叶表面的法向力波动减小,声辐射球上最大噪声声压级也明显减小。
Based on the computational fluid dynamics(CFD) method and noise solved FW-H(Ffowcs Williams-Hawkings) equation,the aeroacoustic noise of rigid coaxial rotor was calculated in hover,and the influence of aerodynamic interference on noise characteristics was analyzed.The study indicated that:in hover stage,the surface pressure of upper and lower rotor blades changed periodically with the rotation of the blade,and there were eight small cycles in one revolution;the periodic variation of the sound source led to inconsistent “superposition effect” produced by the sound pressure at observation points in different directions in the plane of the rotor disk,and the noise level at the intersection of upper and lower rotors was higher than that at other azimuths;due to the time-varying load,there was still significant radiation noise in the direction of the rotation axis,so the noise sound pressure level in this direction was much larger than that of single rotor.With the increase of rotor spacing,aerodynamic interference between twin rotors was reduced,and the normal force fluctuation of the maximum noise sound pressure level on the sound radiation sphere also decreased.
作者
江露生
李尚斌
邱逢昌
樊枫
黄水林
JIANG Lusheng;LI Shangbin;QIU Fengchang;FAN Feng;HUANG Shuilin(National Key Laboratory of Helicopter Aeromechanics,China Helicopter Research and Development Institute,Jingdezhen Jiangxi 333001,China)
出处
《航空动力学报》
EI
CAS
CSCD
北大核心
2024年第8期367-376,共10页
Journal of Aerospace Power
基金
航空基金(201957002004)。