PERFORMANCE AND DYNAMIC STABILITY OF GENERAL-PATH CENTRIFUGAL PENDULUM VIBRATION ABSORBERS

Centrifugal pendulum vibration absorbers are a type of tuned dynamic absorber used for the attenuation of torsional vibrations in rotating and reciprocating machines. They consist of masses that are constrained to move along specific paths relative to the rotational axis of the machine. Previous analytical studies have considered the performance of single absorber systems with general paths and of multi-absorber systems with a specific path type. In this paper, we investigate the performance and dynamic stability of systems comprised of multiple, identical centrifugal pendulum vibration absorbers riding on quite general paths. The study is carried out by considering a scaling of the system parameters, based on physically realistic ranges of dimensionless parameters, which permits application of the method of averaging. It is found that the performance of these systems is limited by two distinct types of instabilities. In one type, the system of absorbers lose their synchronous character, while in the other a classical non-linear jump affects all absorbers identically, leading to highly undesirable system behavior. These results are used to evaluate two common types of absorber paths, namely circles and cycloids, including intentional mistuning of the absorber frequencies. The results are used to make some recommendations about the selection of paths to achieve design goals in terms of absorber performance and operating range. The analytical predictions are confirmed by numerical simulations.