The subcycled newmark algorithm

摘要

The popular Newmark algorithm, used for im- plicit direct integration of structural dynamics, is extended by means of a nodal partition to permit used of different timesteps in different regions of structural model. The algorithm developed has as special case an explicit-ex- plicit subcycling algorithm previously reported by Bel- ytschko, Yen and Mullen. That algorithm has been shown, in the absence of damping or other energy dissipation, to exhibit instability over narrow timestep ranges that be- come narrower as the number of degrees of freedom increases, making them unlikely to be encountered in practice.