Experimental and numerical investigations on an unbalance identification method for full-size rotor system based on scaled model

Perfect balance of rotor systems is difficult to achieved in practical engineering and some amount of unbalance is unavoidable. However, identifying the unbalance value of full-size rotor system is difficult, time-consuming and sometimes dangerous. Aiming at this issue, this paper proposes an unbalance identification method for full-size rotor systems. The unbalance value can be identified through the scaling laws and scaled model, where the scaling laws are developed by incorporating the least squares method and sensitivity analysis. The effectiveness of the proposed method is verified by the numerical and experimental case studies, where the distortion in geometrical dimension is taken into account. The numerical case identifies the unbalance value of a rotor system and evaluate the identification errors. Furthermore, the experimental testing for the prototype and model test rigs is carried out. The results show that the unbalance values can be accurately identified by the proposed method. This allows one to identify the unbalance value of full-size rotor system through a small scaled model.