一种可预测全耦合失谐叶盘受迫响应的误差修正方法

An Approximate Method Applicable to Calculating Forced Response of Mistuned Bladed Disks in Medium Coupling Range

基于叶盘部分失谐和叶盘全局失谐的复合模型,提出了一种可预测全耦合失谐叶盘振动响应的误差修正方法。叶盘的部分失谐反映叶盘的局部特征对系统响应的影响,叶盘的全局失谐反映失谐的总体特征,二者结合可以较为准确地描述失谐叶盘的振动规律。根据近似响应所产生的近似激振力与原激振力的比值,设置误差比例系数来修正近似响应。仿真结果表明,叶盘部分失谐和叶盘全局失谐相结合的方法能够较为准确地预计各种耦合强度下的失谐叶盘受迫振动的共振幅值;同时,误差比例系数的引入可进一步提高预测响应的精度。

Past approximate methods are only applicable to either weak coupling or strong coupling but bring in relatively large errors in the case of medium coupling. We aim to propose an approximate method that is applicable to the entire range of coupling, including medium coupling. Like Ref. 6, we use a partial- entire-combined mistuning model; unlike Ref. 6, our considerations of mistuning are somewhat different from theirs. Based on this model, we present a method for predicting the forced response of mistuned bladed disks within entire coupling range. Partial mistuning features local effects on the response of the whole system; entire mistuning reflects characteristics of all mistuned components. To combine these two models can accurately reflect the characteristics of the vibration of mistuned bladed disks. In the full paper, we explain in detail how to use a correction coefficient to improve the accuracy of the approximated response results in the medium coupling range; this correction coefficient is unnecessary for weak or strong coupling range. This explanation is too complicated to make clear in concise language, so it is omitted here. Numerical results show that partial-entire- combined mistuning model and the correction coefficient can accurately predict the resonant amplitude within the entire range of coupling.