Analysis of steady responses for a frictional oscillator based on the Harmonic Balance-Alternating Frequency/Time Domain Method

Complex contact and frictional behaviors appear on the interface of jointed structures in vibration environment. When subjected to different tangential excitation, the interface may have different frictional behaviors: micro-slip and macro-slip. Solving the steady-state response of frictional oscillators considering micro/macro-slip accurately and efficiently is of great significance to the design and optimization of jointed structures. The steady-state response of single/multi-degree of freedom frictional oscillators was solved by using the continuous spring-slider model (Iwan model) to describe the cross-scale frictional behavior on the jointed surface, and combing the multiple harmonic balance method and the alternating frequency/time domain method. Results show that the method has high accuracy and higher computational efficiency than conventional numerical integration methods. The higher the truncated harmonic order, the more accurate the frictional restoring force. The frequency response analysis shows that the frictional nonlinearity results in nonlinear phenomena of stiffness softening and harmonic resonance for the amplitude-frequency response. © 2020, Editorial Office of Journal of Vibration and Shock. All right reserved.