Theoretical and experimental research on balancing of flexible rotors without trial weights

In order to improve the efficiency of the rotor balancing and solve the problem of the influence coefficient method and the modal balance method which are needed to add trial weights, a balancing method for the high speed flexible rotor without trial weights is established based on the modal balance theory. Firstly, numerical simulation of the dynamic characteristics of the rotor is carried out to obtain modal shapes of the rotor using the finite element software. Then according to a set of real-time measured imbalance transient response of the rotor, the size and orientation of the unbalance of the rotor is calculated by the without trial weights balancing theory. Dynamic balancing tests are carried out on the high speed flexible rotor experiment to verify the correctness of the method. The vibration amplitude of the rotor at the critical speed decreases above 70% on average after just once balance. It shows that the method can calculate the unbalance of a high speed flexible rotor effectively, accurately and quickly.