Affiliation:
1. Department of Mechanical Engineering, University of Genova , Genova 16145, Italy
2. Ansaldo Energia , Genova 16152, Italy
Abstract
Abstract
In some circumstances, it is impossible to exploit resonance crossings to identify the modal properties of rotor disks. In these cases, the identification process must rely on nonsynchronous vibrations and becomes challenging for two reasons. First, the signals are weak (compared to the levels measured during resonance crossings) and random, thus an averaging procedure is necessary. Second, the dynamical system is time-variant due to the variation of the rotor speed. This paper presents a modal identification procedure formulated in the framework of the time–frequency analysis. A region of the time–frequency plane is stretched to map the system into a fictitious linear time-invariant (LTI) system. Then, the power spectral density function (PSD) of the response is computed by an averaging procedure. Finally, the modal properties are estimated through an output-only modal identification algorithm. The procedure is applied to simulated and experimental data regarding a bladed disk of a steam turbine.
Subject
Mechanical Engineering,Energy Engineering and Power Technology,Aerospace Engineering,Fuel Technology,Nuclear Energy and Engineering
Reference24 articles.
1. Vacuum Spin Test Series of a Turbine Impeller With Focus on Mistuning and Damping by Comparing Tip Timing and Strain Gauge Results,2015
2. Comparison of Blade Tip Timing With Strain Gauge Data for Evaluation of Dynamic Characterization of Last Stage Blade With Interlocked Shroud for Steam Turbine,2018
3. An Approach for Estimating the Effect of Transient Sweep Through a Resonance;ASME J. Eng. Gas Turbines Power,2016
4. Wavelet-Based Identification of Rotor Blades in Passage-Through-Resonance Tests;Mech. Syst. Signal Process.,2018
5. Modal Identification of Dynamically Coupled Bladed Disks in Run-Up Tests,2016
Cited by
1 articles.
订阅此论文施引文献
订阅此论文施引文献，注册后可以免费订阅5篇论文的施引文献，订阅后可以查看论文全部施引文献