Evaluation on the Global Response Characteristics of a Rotor/Stator Rubbing System: Experiment and Dynamic Simulation

The global response characteristics of rotor/stator rubbing systems are critical for the optimal design and safe operation of rotating machinery. Based on the mathematical model, numerical simulation and theoretical analysis have been widely carried out to study the regions of different responses, which have not been globally explored and evaluated by experiments with the unified parameters of a mathematical and physical model. Thus, the existence conditions of the global responses of a rubbing rotor are experimentally investigated and then quantitatively compared with theoretical solutions and dynamic simulation results. With the equivalent stiffness and the kinetic dry friction identified by the aid of a new voltage divider, the rubbing rotors are accurately tested by the new experimental technique and dynamically simulated by rigid-flexible coupling technique. From the comparison results of orbit and full spectrum, it is shown that the response characteristics of no rub motion, synchronous full annular rub, partial rub, and dry friction backward whirl obtained by experiment and dynamic simulation are in good agreement with theoretical solutions. Then, it is also concluded that all boundaries of the existence/co-existence regions of the whirling motions are proved to be valid. Moreover, stick-slip oscillation is detected in the rotor/stator testing system.