Abstract

In this paper we examine Targeted Energy Transfers
(TETs) and nonlinear modal interactions occurring in a thin
cantilever plate lying on an elastic foundation with strongly
nonlinear lightweight attachments of different configurations.
Under shock excitation of the plate we systematically study,
nonlinear modal interactions and passive broadband targeted
energy transfer phenomena between the plate and attachments of
the following configurations: a single ungrounded, strongly
(essentially) nonlinear single-degree-of-freedom (SDOF) NES;
multiple SDOF attachments attached at different points of the
plate; and a single multi-degree-of-freedom (MDOF) attachment
with multiple essential stiffness nonlinearities. We perform
parametric studies by varying the parameters and location of the
attachments, in order to optimize TETs from the plate to the NES.
We examine in detail the underlying mechanisms influencing
TETs by means of Hilbert-Huang Transforms in combination with
Wavelet Transforms. These transforms enable one to
systematically study the strong modal interactions between the
essentially nonlinear attachments and different plate modes. The
efficacy of using this type of essentially nonlinear attachments as
passive absorbers of broadband vibration energy is discussed.