Prediction of Vibration Response Caused by Rotating Machinery

Abstract

Excitation energy of rotating machinery propagates through the connection paths resulting in vibration responses at the structures such as machine foundations. Accurate prediction of these vibration responses at a point of a complex structure, where the operational behavior cannot be measured directly, is an important engineering problem for design optimization, component selection and condition monitoring. The main step of the prediction is to identify the internal forces acting on the connection paths of the machinery. At the circumstances where direct measurement is impossible or impractical due to physical constraints, an indirect approach is to identify the exciting forces based on multiplication of an inverted frequency response functions (FRFs) matrix and a vector of vibration responses measured at the points where the exciting forces are transmitted through. The aim of this paper is to present matrix inversion method to identify the exciting internal forces and hence, predict the vibration response at the point of interest.

Keywords

• vibration response,matrix inversion,cross-coupling,rotating machinery

References

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