Dynamic study of viscoelastic rotor: Reduction of higher order model using different techniques

Abstract Finite element formulation of general viscoelastic rotor reaches a higher order configuration due to the inherent material properties, resulting in a complicated system. The interest of this paper is the application of suitable reduction technique, which helps to rewrite the system equations with important coordinates. In order to understand the best methodology to reduce the higher order model, two different reduction techniques have been used: (i) Iterative Improved Reduction System, (ii) Balanced Realization System. In first case, an iterative algorithm is used to improve the transformation matrix by achieving convergence. Whereas, in second case, Hankel Singular Value Decomposition assures to predict the most controllable and observable states, which helps to reduce the system matrices accurately. The benefit of implementing these techniques is to tackle the problems caused due to skew-symmetric matrices that emanate for an addition of internal material damping and gyroscopic effects. The effectiveness of reduced model is well examined using various dynamic parameters. The agreement between reduced and original system predict the usefulness of this study.

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