首先建立了失谐叶片-轮盘的数学模型,以模态综合法为基础给出了失谐叶片-轮盘的模态问题计算方法;并利用某压气机叶片-轮盘对该方法进行了验证.与ANSYS软件对比,前300阶固有频率最大偏差为0.62%,在计算区间的位移响应最大偏差为3.45%.然后研究了标准差为0.01的随机失谐现象,最大位移幅值响应曲线的带宽从谐调时的2Hz左右扩展为10Hz左右,振动出现了明显的局部化现象,表明失谐容易使叶片过早出现高周疲劳,严重影响了叶片的安全性.本研究获得的随机失谐自由叶片振动特性分析结论,可以为整圈叶片在实际气流激振力作用下的振动安全性考核提供参考.%Firstly, the mathematical model was established to analyze mistuned blade-disk. In order to solve modal problem of mistuned blade, a new algorithm was developed based on modal synthesis method. The compressor blade-disk was used to demonstrate the validity of this algorithm. Compared with ANSYS, the maximum natural frequency deviation with modal synthesis method was 0.62% and the maximum displacement response was 3.45% in calculation frequency intervals. Secondly, standard deviation of 0.01 was simulated to analyze random mistuned blade-disk. The results showed the bandwidth of the maximum displacement response curve expanded from 2Hz to 10Hz, and random mistuning phenomenon caused obvious vibration localization, which could lead to high cycle fatigue of blade-disk and have tremendous impact on blade safety. The analytical conclusion of vibration characteristics of free standing blade with random mistuning could be considered as a reference for the vibration safety assessment of interlocked blade under the impact of actual flow induced force.
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