颤振求解是一种研究参数(如空速)变化的特征值问题.在颤振模态判别和防颤振设计中,需要正确确定各阶模态对应的特征值随参数变化时的前后对应关系,避免出现模态交叉.针对颤振求解p-k法,发展了一种基于特征值摄动理论的模态跟踪技术——预测跟踪法,它利用特征值及左、右特征向量信息求解下一空速点的特征值估计量,以估计量为参考对特征值进行排序,将预测跟踪法和相似排序法、正交检验法进行了对比.数值结果表明:预测跟踪法比相似排序法和正交检验法具有更好的模态跟踪效果.
Flutter solution is an eigenvalue problem which has variable parameters (such as air speed). In flutter mode identification and flutter prevention, the correspondence between the baseline and perturbed eigenvalues due to parameter variation should be determined accurately, and mode crossing should be avoided. For mode tracking in flutter solution p-k procedure, the forecast tracking method was developed, which was based on the perturbation theory of eigenvalues. The method used the baseline eigenvalues and the left and right eigenvectors to estimate perturbed eigenvalues, and sorted modes by their estimated values. The forecast tracking method was compared with two existing methods, one was similarity sorting method, the other was orthogonality check method. Two testing cases were used to validate the effectiveness of the methods. The numerical results show that the forecast tracking method is better than the existing methods in effects of mode tracking.