Impact of Periodic Path Imperfections on Dynamic Response of Centrifugal Pendulum Vibration Absorbers

Centrifugal pendulum vibration absorbers are order-tuned masses oscillating on purposefully designed cutouts with the support of cylindrical rollers. The complementary geometric shapes of cutouts and rollers, in combination, form the path that absorbers take during the centrifugal pendulum vibration absorber (CPVA) operating cycle. The path of each absorber can be different from the ideal baseline design due to manufacturing errors or wear as a result of prolonged use under heavy operating conditions. These aberrations of the path geometry may lead to serious loss in the vibration reduction performance due to asynchronous and localized response of absorbers. This work considers periodic waviness-type path imperfections, which are usually caused by machining errors and investigates their impact on CPVA’s forced vibration response. Waviness imperfections are analyzed in different designs, including cyclically symmetric and asymmetric configurations by evaluating vibration reduction capability and absorber oscillation amplitudes. The nonlinear dynamic model of the CPVA developed and utilized in this study includes translational and torsional dynamics of the rotor and oscillations of absorbers. Details of the dynamic model and the definition of waviness-type path imperfection are presented initially. The impact of number of absorbers, number of nonideal absorbers and influence of translational dynamics of the rotor are investigated in terms of their interaction with the waviness order and amplitude. As a result, a geometric tolerance recommendation is made on the circularity of the cutouts to circumvent the significant performance degradation linked to absorber path waviness errors.