In this work, an integrated testing and calibration procedure is presented for performing mistuning identification (ID) and traveling wave excitation (TWE) of one-piece bladed disks (blisks). The procedure yields accurate results while also being highly efficient and is comprised of three basic phases. First, selected modes from a tuned blisk finite element model are used to determine a minimal set of measurement degrees of freedom (and locations) that will work well for mistuning ID. Second, a testing procedure is presented that allows the mistuning to be identified from relatively few vibration response measurements. A numerical validation is used to investigate the convergence of the mistuning ID results to a prescribed mistuning pattern using the proposed approach and alternative testing strategies. Third, a method is derived to iteratively calibrate the excitation applied to each blade so that differences among the blade excitation magnitudes can be minimized for single blade excitation, and also the excitation phases can be accurately set to achieve the desired traveling wave excitation. The calibration algorithm uses the principle of reciprocity and involves solving a least squares problem to reduce the effects of measurement noise and uncertainty. Because the TWE calibration procedure re-uses data collected during the mistuning ID, the overall procedure is integrated and efficient.

A novel measurement point selection (MPS) technique for bladed disks (blisks) is presented and applied to a new modal damping identification method. When gathering data to be used for applications such as mistuning identification in blisks, it is important to measure points which provide sufficient and accurate information for the analysis. However, to reduce the experimental time and cost, the measurement points should be chosen optimally so that the minimum number of measurements have to be collected. This paper discusses a modified form of the effective independence distribution vector (EIDV) method presented by Penny et al. and adapted by Holland et al. The key novel aspect of the proposed method is that it uses only single sector-level calculations instead of the whole system. A residual weighting optimizes the MPS technique for noisy measurements. The method presented is equivalent to the full system EIDV method, but it decreases the computational cost, increases the robustness of the identification, and minimizes the measurement time. Also, a novel method to identify damping parameters for each mode in a frequency range of interest is presented. This method utilizes the proposed MPS technique to increase the accuracy of the identification. Measurement locations and modal damping results for a 30 degree of freedom system and a blisk with a complex geometry are presented. Using the proposed methodologies it is possible to obtain an accurate modal damping identification with a decreased computational and measurement cost.

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