MODELLING LIQUID–STRUCTURE INTERACTIONS WITHIN THE FRAMEWORK OF STATISTICAL ENERGY ANALYSIS

This paper presents some work undertaken as part of a managed programme in statistical energy analysis (SEA) and its application to problems with liquid loadings. A study of vibrations involving a coupled fluid–structural system has been carried out and the results from this used to examine aspects of statistical energy analysis modelling in this context. The study involved a series of numerical analyses undertaken using the finite element method. In dealing with coupled systems consisting of fluids and structures two approaches were employed: direct FE models using elements formulated for acoustic and solid domains, and modal representation of the solids in the coupled models. Dynamic response analysis was then performed for the combined models. A wide spectrum of energy levels was obtained when the models were subjected to various types of loading. Based on these numerical analysis results a number of SEA models were established with different topological interconnections. These were then used to make forced response predictions that could be compared with full finite element calculations. Various test case results are presented and associated conclusions drawn from the study. It is shown that the more complex SEA models do not necessarily give improved accuracy.