基于接触刚度分布特性的叶片振动响应分析

According to the non-uniform distribution characteristics of contact stiffness between interfaces of the zigzag shroud， a method for calculating contact stiffness was proposed based on the combination of definition and finite element calculation. On this basis， the micro-macro-slide friction model was applied to shroud contact interfaces，and the frictional force expressions were derived in micro-slide state and the macro-slide state. The harmonic balance method was used to convert the nonlinear friction force into the equivalent stiffness and equivalent damping. Considering the dynamic change of the relative displacement amplitude between interfaces， an iterative solution method for analyzing vibration response was proposed. Compared with experimental data of vibration response of cantilever beam with frictional damping structure provided in literature， the amplitude error near the resonance peak was 1.99 mm，and the relative error rate was 3.9%. The maximum error of the amplitude was 5.53 mm，which appeared far away from the resonance peak. It was believed that the accuracy of the response analysis method was relatively high. This method was applied to the shrouded blade，and the results showed that the amplitude was 0.56 mm when the excitation force frequency was 812.3 Hz.