Nonlinear dynamic analysis of pipe assemblies via experimental characterisation and nonlinear dynamic reduced order modelling

Abstract

In this thesis a new reduced order modelling methodology is presented with the aim of calculating the nonlinear dynamic response of fuel manifold alike assemblies. This bottom-up approach started with the experimental characterisation of the individual components that typically form part of a fuel manifold, to later characterise the interaction between them in more complex subassemblies. Once the different elements and subassemblies were characterised, two different model designs were proposed: an implicit 6 DOF/node model and a hybrid 3 DOF/node model. The design parameters of both models were obtained by means of model updating and optimisation against experimental data. Finally, an analytical study on the influence of multiple nonlinearities was performed in order to determine the dynamic trend when an increasing number nonlinear joints are added into a certain system