Black-Box modelling for the prediction of nonlinear riser dynamics under combined parametric and lateral excitation using the Volterra-Wiener theory

摘要

The present paper deals with the problem of the dynamic behaviour of riser-type structures for marine applications subjected to combined axial and transverse motions. The solution method is based on a Galerkin type semi-analytical formulation. The features of the nonlinear impacts of the response and the significance of each mode are assessed using an input-output, black-box model based on the Volterra-Wiener theory technique for nonlinear systems. The result is a low-nonlinearity-order model for each one of the significant modes of the riser. The models obtained can be effectively parameterised and formulated; the parameters of the models can be determined systematically by a method relying on numerically calculated modal responses of the riser to single-tone harmonic inputs.