Partitioned procedures for the transient solution of coupled aeroelastic problems - Part II: Energy transfer analysis and three-dimensional applications

We consider the problem of solving large-scale nonlinear dynamic aeroelasticity problems in the time-domain using a fluid/structure partitioned procedure. We present a mathematical framework For assessing some important numerical properties of the chosen partitioned procedure. and predicting its performance for realistic applications. Our analysis framework is based on the estimation of the energy that is artificially introduced at the fluid/structure interface by the staggering process that is inherent to most partitioned solution methods. This framework also suggests alternative approaches for time-discretizing the transfer of aerodynamic data from the fluid subsystem to the structure subsystem that improves the accuracy and the stability properties of the underlying partitioned method. We apply this framework to the analysis of several partitioned procedures that have been previously proposed for the solution of nonlinear transient aeroelastic problems. Using two- and three-dimensional, transonic and supersonic. wing and panel aeroelastic applications. we validate this framework and highlight its impact on the design and selection of a staggering algorithm for the solution of coupled fluid/structure equations. (C) 3001 Elsevier Science B.V. All rights reserved.