Dynamic behaviours of multiwall boron nitride nanotubes (MWBNNTs) with finite length were studied by employing continuum structure. Multiple elastic shells with nonlinear model of van der Waals interactions were used for developing an inclusive and inexpensive dynamical model of MWBNNTs. The systems of coupled partial differential equations were solved by applying the finite element method. Whole or part of thin and bulky MWBNNTs were exposed to external pressure impact and dynamical treatment were investigated and precision of results were checked by evaluating the answers with those found by other methods. Both deflection and stress studies were carried out for tubes ofMWBNNTs and the influences of longitudinal wave caused by external pressure impact were considered in MWBNNTs. Also, time history diagrams of MWBNNTs with impact of initial longitudinal deflection were investigated and the extension of the longitudinal waves through the length of layers were shown and so, wave speed was determined.

Keywords