Experimental Modal Analysis of a Turbogenerator Rotor

This research presents a methodology for implementing a modal testing procedure on a turbogenerator rotor to identify its natural frequencies and corresponding mode shapes. Experimental modal analysis is performed using an impact hammer and specialized signal processing software under two distinct rotor configurations. The measured modal parameters are then compared to assess the influence of rotor stiffness in different directions. Subsequently, a numerical model of the rotor is developed using Madyn ۲۰۰۰ software to determine the natural frequencies and mode shapes under free boundary conditions. A comparison between the experimental modal test outcomes (natural frequencies and mode shapes) and the numerical analysis results from Madyn is presented. The natural frequencies obtained from the experimental tests are approximately the same; however, the frequencies obtained from the simulation are up to ۵.۶% higher than the experimental results. The mode shapes extracted from both the experimental tests and simulations show reasonably good agreement.

کلیدواژه ها:

experimental modal test ، bump test ، high power generator ، rotor dynamics