A novel nonlinear approach to suppress resonant vibrations

A novel nonlinear approach to suppress resonant vibrations is presented by employing a single degree of freedom transmissibility system, which utilises a nonlinear damping element. The study shows that a nonlinear damping element can reduce the output energy at the driving frequency and at the same time spread the output signal energy over a wider range of harmonics. It is also shown that the reduction becomes larger as the nonlinear damping characteristic gets stronger and in most cases, the power at the harmonics in the Output spectrum is much less when the nonlinear damping characteristic is an odd function. Hence, an odd nonlinear damping element can be designed and introduced between the incoming signal and the system of interest to suppress resonant vibrations. An expression is derived to express the transmitted force spectrum in terms of the nonlinear generalised frequency response functions, to clearly reveal how the energy, at the excitation frequency, is modified by the nonlinearity. (C) 2008 Elsevier Ltd. All rights reserved.