报告题目：An adaptive algorithm for mid-frequency sweep problems
报 告 人：吴柏生教授（广东工业大学机电工程学院）
Frequency response problems arise in many structural dynamic applications. The computational cost of frequency response analyses within a frequency band of interest may be high for large-scale problems because each structural response evaluation requires the solution of a system of equations. A new method for calculating frequency responses in a frequency band of a structure with proportional damping is proposed. The Sturm sequence numbers are first applied to adaptively determine the number of middle modes to be calculated. The unknown low- and high-mode contributions are approximated by the partial sum of the constructed convergent series. The number of the terms in the sum is adaptively determined by using the newly proposed iterative algorithm at left or light ends of the frequency band only. The resulting analytical expression of frequency responses is valid for the entire frequency band. Finally, two numerical examples are given to illustrate the accuracy and effectiveness of the proposed method. The results show that compared with the full method for frequency response analysis, the present method can significantly reduce the CPU time.