Abstract:Dynamic of double rubbing fault in rotor system was analyzed by harmonic component characteristic in harmonic balance theory, method for quantitative diagnosis double rubbing fault locations in rotor system was proposed based on that the ratio of harmonic component of rubbing fault responses is equal to the ratio of corresponding element in frequency response function matrix of fault-free in rotor system and the difference between the any one order harmonic component of fault-free and fault in the three nodes responses is utilized. The double rubbing fault locations in fault rotor system is identified by the three nodes vibration response data in rubbing fault-free and fault rotor respectively, the correctness and feasibility of the method are verified by the numerical simulation experiment.