Efficient modelling and accurate knowledge of the mechanical behaviour of the reactorcore are needed to estimate the effects of seismic excitation on a nuclear power plant. Thepresence of cooling water flow (in PWRs) gives rise to fluid structure interaction phenomena.Modelling of fluid structure interactions on fuel assemblies is thus of fundamentalimportance in order to assure the safety of nuclear reactors. The main objective of thePhD project which is presented in this document is to investigate fluid structure interactionsin order to have a better understanding of the involved phenomena. Both modellingand experimental approach are considered. A new simplified linear model for fluid structureinteractions is developed by using the potential flow theory for fluid force modellingwhile the Euler-Bernoulli beam model is used for the structural part. The model, is firstdeveloped for a single cylinder and it is validated with reference works in literature. Theeffects of the confinement size and of the wavenumber are investigated. The potential flowmodel developed for a single cylinder, is thus extended to a multi cylinders geometry. Theexperimental approach is thus needed in order to validate the developed model. A newexperimental facility, ICARE, is designed in order to investigate fluid structure interactionphenomena on half scale fuel assemblies. In this document, the results provided bydisplacement and LDV measurements are widely analysed. The dynamical behaviour ofthe fuel assembly and coupling effects are investigated. Calculations are compared to theexperimental results in order to validate the model and to analyse its limits. The model isin agreement with experimental results regarding the added mass effect. In addition, themodel qualitatively predicts couplings effects on different directions. As a drawback, thepotential flow model cannot predict added damping effects, which are mainly due to viscousforces. Finally in this document another application of the developed model is described.The model is used in order to simulate experiments performed on a surrogate fuel assemblyin the experimental facility installed at George Washington University (GWU). The modelis able to predict and to provide a valid interpretation for the water flow perturbation dueto the motion of the excited assembly. The thesis concludes with perspectives for furtherimprovements of the model, by integrating viscous terms in the equations. Work needs tobe carried out on the analysis of Particle Image Velocimetry (PIV) data collected duringICARE experimental campaigns.

Containing papers presented at the Seventh International Conference on the topic, this book covers new developments in fluid structure interaction problems. First organised in 2001, the conference includes contributions from international experts on a variety of topics, including: Structure response to severe shock and blast; Hydrodynamic forces; Aeroelasticity; Computational methods; Flow induced vibrations; Experimental studies and validation; Bioengineering applications; Offshore structures; Soil structure interaction.

This book contains a collection of 11 research and review papers which have been contributed by each research unit joining the MIUR funded project: "Influence of vorticity and turbulence in interactions of water bodies with their boundary elements and effects on hydraulic design". The book features state-of-the-art Italian research devoted to the topic of fluid-structure interaction.

Publishing papers presented at the Fourth International Conference on Fluid Structure Interactions, this book features contributions from experts specialising in this field on new ideas and the latest techniques. A valuable addition to this successful series and will be of great interest to mechanical and structural engineers, offshore engineers, earthquake engineers, naval engineers and any other experts involved in topics related to fluid structure interaction. Topics covered include: Hydrodynamic Forces; Response of Structures including Fluid Dynamic; Offshore Structure and Ship Dynamics; Fluid Pipeline Interactions; Structure Response to Serve Shock and Blast Loading; Vortex Shedding and Flow Induced Vibrations; Cavitations Effects in Turbo Machines and Pumps; Wind Effects on Bridges and Tall Structures; Mechanics of Cables, Rivers and Moorings; Building Biofluids and Biological Tissue Interaction Problems in CFD; Experimental Studies and Validation; Vibrations and Noise; Free Surface Flows and Moving Boundary Problems.

This book discusses various passive and active techniques for controlling unsteady flow dynamics and associated coupled mechanics of fluid-structure interaction. Coupled multiphysics and multidomain simulations are emerging and challenging research areas, which have received significant attention during the past decade. One of the most common multiphysics and multidomain problems is fluid-structure interaction (FSI), i.e., the study of coupled physical systems involving fluid and a structure that have a mechanical influence on each other. Regardless of the application area, the investigation toward modeling of fluid-structure interaction and the underlying mechanisms in dealing with coupled fluid-structure instability with real-world applications remains a challenge to scientists and engineers. This book is designed for students and researchers who seek knowledge of computational modeling and control strategies for fluid-structure interaction. Specifically, this book provides a comprehensive review of the underlying unsteady physics and coupled mechanical aspects of the fluid-structure interaction of freely vibrating bluff bodies, the self-induced flapping of thin flexible structures, and aeroelasticity of shell structures. Understanding flow-induced loads and vibrations can lead to safer and cost-effective structures, especially for light and high-aspect ratio structures with increased flexibility and harsh environmental conditions. Using the body-fitted and moving mesh formulations, the physical insights associated with structure-to-fluid mass ratios, Reynolds number, nonlinear structural deformation, proximity interference, near-wall contacts, free-surface, and other interacting physical fields are covered in this book. In conjunction with the control techniques, data-driven model reduction approaches based on subspace projection and deep neural calculus are covered for low-dimensional modeling of unsteady fluid-structure interaction.

This book is a compilation of papers covering advanced topics in the potential flow of fluids by leading authorities in the field. The book covers the subject of reflection and transmission of solitary waves, methods of estimating wave effects on large offshore structures, gravity waves on the surface of deep water from the viewpoint of nonlinear mechanics, wave breaking in shallow water, finite difference techniques for 2D and 3D wave breaking phenomena, the development of a powerful numerical method for computing the second-order wave load on 3D bodies, and finally, mathematical models and solutions of different theories related to the interaction between water waves and different offshore structures, in particular, circular cylinders and spherical structures.