The importance of phase-locking in nonlinear modal interactions

Abstract

In nonlinear systems the constituent linear modes may interact due to internal resonance. In this paper we classify two distinct classes ofmodal interactions: phase-locked interactions, in which there is a specific phase between the interacting modes; and phase-unlocked interactions, in which the modes may interact regardless of their phase. This discussion is accompanied by the study of an example structure in which both classes of interaction may be observed. The structure is used to demonstrate the differences between phase-locked and phase-unlocked interactions, both in terms of their individual influence on the response, and in terms of their influence on each other when both classes of interactions are present.