The modified balance method based on precession decomposition

When balancing an anisotropically supported rotor, the effect of conventional Influence Coefficient Method which using the vertical or horizontal vibration individually is unstable and influenced by the direction of the transducers. This paper proposes a modified method which takes two perpendicular transducers into account. In this method, an elliptical whirl orbit of unbalance response is decomposed into forward precession and backward precession, then, the amplitude and phase of the former was used to substitute the traditional unbalance response to fulfill the balance procedure. Numerical examples show that the modified method yields a more objective and accurate result and keeps a highly compatibility with the conventional one when nonlinear factors are neglected. The efficiency of the new method is verified by an experiment on rotor test rig.