Study on Vibration Characteristics of Mistuned Bladed Disk(Vibration Response Analysis by Reduced Model FMM)

Abstract

It is well known that the asymmetric vane spacing can result in decreased levels of the excitation at specific frequencies. In the previous paper, the resonant response reduction of the mistuned bladed disks due to the asymmetric vane spacing was studied by use of the equivalent spring-mass model. Although the mistuned bladed disk should be analyzed by FEA (Finite Element Analysis) to accurately evaluate the resonant response reduction effect of the asymmetric vane spacing, it is unrealistic due to enormous computational time. Therefore, in this study, the mistuned bladed disk is modeled by use of FMM (Fundamental Mistuning Model) to evaluate the resonant response reduction effect of the asymmetric vane spacing accurately and practically. First, the frequency response analysis of a simple mistuned bladed disk consisting of flat plate blades is carried out for the symmetric and asymmetric vane spacing, using both of FMM and the direct FEA, and the calculated results are compared to confirm the validity of FMM. Second, the frequency response analysis of a realistic bladed disk is carried out for the symmetric and asymmetric vane spacing, using FMM, to examine the effect of the resonant response reduction effect.

Passive Vibration Reduction Analysis of the Mistuned Blisk Deposited Hard Coating Using Modified Reduced-Order Model

“…Similarly, based on exact calculation of the response of a mistuned system using response levels for the tuned assembly together with a modification matrix constructed from the frequency response function (FRF) matrix of the tuned system and a matrix describing the mistuning, a new method for the dynamic analysis of mistuned bladed disks was presented by Petrov [56]. Subsequently, a simplified SNM called FMM (fundamental mistuning model) was developed by Feiner and Griffin [57], and then used by Chan and Ewins [58] and Kaneko et al [59] to study natural characteristics and forced vibration response of the mistuned bladed disks, respectively. In addition, the RM (receptance method) and the CMM (component mode mistuning) method were proposed by Yang and Griffin [60] and Lim et al [61] to study vibration characteristics of the mistuned bladed disks, respectively.…”

Vibration Response Analysis of Mistuned Bladed Disk Consisting of Directionally Solidified Blade

“…In the analysis, the large-scaled FE model used in the actual blade design is utilized. However, because it is difficult to carry out the vibration response analysis using the large-scaled FE model directly due to the enormous computational time, the reduced order model FMM is applied [10][11][12][13]. The vibration response analysis of the mistuned bladed disk consisting of CC blades is also carried out in the same procedure.…”

“…(3) The eigenvalue analysis of a mistuned bladed disk is carried out, using the sophisticated reduced model FMM, because it is not practical to apply the FEA directly to the eigenvalue analysis of the mistuned bladed disk. The frequency response analysis of the mistuned bladed disk is carried out by the conventional modal analysis method, using the modal parameter obtained by FMM [10][11][12][13].…”