An identification scheme for bearing dynamic characteristics by using unbalance response measurements is developed for rigid rotor systems supported by two anisotropic bearings. This scheme uniquely identifies the bearing dynamic coefficients, consisting of four damping and four stiffness coefficients, utilizing unbalance response measurements from four sensors at two locations for two different trial unbalance conditions. The fundamental assumption made in the proposed method is that the inertia properties of the rigid rotor are known. The procedure of identifying bearing dynamic coefficients by using the proposed method is presented and demonstrated through a numerical example.
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