超高速空气动静压轴承-转子系统不平衡量在线识别研究

Aiming at the problem that dynamic balancing method without trial weights neglects the bearing nonlinearity under the ultra-high speed, causing the low accuracy of multifaceted unbalance identification, an online unbalance identification method for hybrid gas bearing-rotor system considering the nonlinear gas film force is proposed. Firstly, a numerical solution termination method based on spectral amplitude is developed and a dynamic model of hybrid gas bearing-rotor system considering nonlinear transient gas film force is established to build an unbalance response database. Moreover, based on the hybrid genetic simulated annealing algorithm with both global optimization and local search capability, online unbalance identification of bearing-rotor systems under ultra-high speed is realized. The simulation and test results show that compared with the traditional time-period method as the termination condition of nonlinear dynamics calculation, the efficiency of the spectral amplitude method is greatly improved. Furthermore, compared with the unbalance identified by linear bearing force assumption, the online unbalance identification method considering the nonlinear gas film force improves the accuracy of unbalance identification, which can accurately identify the unbalance magnitude and phase of rotor system, and provide technical support for ultra-high speed online dynamic balance test.