采用非接触式非侵入式的测量方法实现航空发动机叶盘振动测量，对发动机研制、试验、运行安全具有重要意义。提出基于声模态分解的叶盘同步振动辨识方法，在某三级风扇试验器的进气道布置环形声阵列，作为参照并在动叶布置若干应变片，开展升降速试验。分析声压信号的叶片通过频率随转速的变化规律，对动叶一阶通过频率下的声阵列信号进行声模态分解，结合应变片实测的动叶坎贝尔图，建立主导声模态数与叶盘节径数的映射关系。声场和动应力测试结果表明：当主导声模态数与叶盘节径相等时，动叶发生共振现象，此时可有效地对风扇叶盘同步振动进行辨识；动叶与前后叶排静叶都存在转静干涉现象，声压信号呈现为窄带宽频，形成声模态离散，造成动叶表现为多模态振动；声压信号是叶片不同振动模态的气动载荷分布的综合反映，具有好的灵敏性和完备性，可实现航空发动机动叶非接触式非侵入式振动测量。

It is important to apply the non-contact and non-invasive approach to the vibration measurement of aero-engine blisks in aero-engine development， experiments and safety operation. An acoustic mode decomposition based approach is proposed to realize the identification of synchronous vibration of the blisk. The run-up and run-down experiment of a three-stage fan test rig is conducted， where the ring microphone array is placed at the inlet duct and several strain gauges are glued on the rotor blade. The Blade Passing Frequency （BPF） of the acoustic pressure signal is analyzed with respect to the rotational speed. With the mode decomposition at BPF and the Campbell diagram， the mapping relationship between the dominant mode order and the nodal diameter number of the blisk is established. The results of acoustic and vibration tests show that the resonance of the blade occurs when the number of the dominant mode order equals to the nodal diameter number of the blisk， where the proposed approach can effectively identify the synchronous vibration parameters of the blisk； the rotor blades have interacted with both the forward and backward rows of stator vanes， where the generated acoustic modes hold broadband characteristics and the mode scattering phenomenon occurs， leading to the multi-modal vibration of the rotor blade； the acoustic pressure can sensitively mirror different modes of blade vibration， and hence can be employed for the non-contact and non-invasive measurement of the aero-engine vibration.