Advanced Numerical Modelling of Wave Structure Interaction

Description

This book will serve as a reference guide, and state-of-the-art review, for the wide spectrum of numerical models and computational techniques available to solve some of the most challenging problems in coastal engineering. The topics covered in this book, are explained fundamentally from a numerical perspective and also include practical examples applications. Important classic themes such as wave generation, propagation and breaking, turbulence modelling and sediment transport are complemented by hot topics such as fluid and structure interaction or multi-body interaction to provide an integral overview on numerical techniques for coastal engineering. Through the vision of 10 high impact authors, each an expert in one or more of the fields included in this work, the chapters offer a broad perspective providing several different approaches, which the readers can compare critically to select the most suitable for their needs. Advanced Numerical Modelling of Wave Structure Interaction will be useful for a wide audience, including PhD students, research scientists, numerical model developers and coastal engineering consultants alike. Cover Title Page Copyright Page Foreword Table of Contents Introduction Chapter 1 Wave Generation and Absorption Techniques 1 Introduction 2 Review of wave generation and absorption methods 2.1 Static boundary wave generation and absorption boundary conditions 2.2 Relaxation zones 2.3 Internal wave makers 2.4 Moving wavemakers with active absorption 3 Discussion References Chapter 2 Wave Propagation Models for Numerical Wave Tanks 1 Introduction 2 Historical development 2.1 BEM models 2.2 FEM models 2.3 Spectral models 2.4 Fully Lagrangian models 3 Lagrangian numerical wave model 3.1 Mathematical formulation 3.2 Numerical scheme 3.3 Numerical dispersion relation and dispersion correction 3.4 Numerical treatment of breaking 3.5 Numerical efficiency 3.6 Model validation 4 Model application to the evolution of extreme wave groups 5 Model application to waves on sheared currents 6 Concluding remarks References Chapter 3 Wave Breaking and Air Entrainment 1 Introduction 2 Physics of breaking 2.1 Wave breaker types 2.2 Flow structure 3 Numerical model 4 Wave breaking of unstable sinusoidal wave 4.1 Initial configuration 4.2 Splash-up and large vortical structures 5 A new type of vortical structures under breaking waves 6 Discussion and future work References Chapter 4 Air Compressibility and Aeration Effects in Coastal Flows 1 Introduction 2 Flow model for dispersed water waves 2.1 Mathematical model 3 Numerical Method 3.1 Treatment of the advection equation 3.2 Spatial discretisation 3.3 The HLLC Riemann solver 3.4 Temporal discretisation 4 Results 4.1 1D problems 4.2 Free drop of a water column in a closed tank 4.3 Underwater explosion near a planar rigid wall 4.4 Water entry of a rigid plate 4.5 Plunging wave impact at a vertical wall 5 Conclusions References Chapter 5 Violent Wave Impacts and Loadings using the δ-SPH Method 1 Introduction 2 Governing equations 3 The δ-SPH scheme 4 Modelling solid bodies 4.1 The ghost-fluid method 4.2 Evaluation of Forces and Torques through the ghost-fluid method 4.3 Algorithm for fluid-body coupling 5 Energy balance 6 Applications 6.1 Prediction of water impacts 6.2 Extreme loads on a Wave Energy Converter (WEC) 7 Conclusions References Chapter 6 Wave and Structure Interaction Porous Coastal Structures 1 Introduction 2 Literature review 3 Mathematical formulation 3.1 Definitions 3.2 RANS equations 3.3 Volume-Averaged RANS equations 3.4 Closure 3.5 Turbulence modelling 3.6 Discussion 4 Numerical model 5 Applications: Solitary wave impacting into a rubble mound breakwater 5.1 Numerical setup 5.2 Numerical results 5.3 Concluding remarks 6 Applications: Wave and sediment grain interaction by a nonbreaking solitary wave on a steep slope 6.1 Introduction to DEM 6.2 Numerical setup 6.3 Numerical results 6.4 Concluding remarks 7 Final remarks References Chapter 7 CFD Modelling of Scour in Flows with Waves and Currents 1 Introduction 2 Types of sediment transport models in CFD 3 The scourFOAM model 3.1 Governing equations 4 Numerical solution technique 4.1 The solver 4.2 Boundary and initial conditions 4.3 Solution procedure 5 Model applications 5.1 2D scour application 5.2 3D scour around a complex foundation 6 Conclusions References Chapter 8 A Coupling Strategy for Modelling Dynamics of Moored Floating Structures 1 Introduction 2 Uncoupled numerical models 2.1 Fluid dynamics 2.2 Solid dynamics 3 An overview of fluid-structure coupling schemes 3.1 Monolithic schemes 3.2 Partitioned schemes 3.3 Coupling instabilities 4 Coupling strategy 4.1 Fluid-structure coupling 4.2 Fluid-mooring coupling 4.3 Mooring-structure coupling 5 Case studies 5.1 Validation of FSI for floating bodies 5.2 Validation of mooring model 5.3 Moored floating bodies: the OC4-DeepCwind validation case 6 Conclusions Appendices A On limitations and way forward B On software development References Future Prospects 1 The lattice Boltzmann method 2 Arbitrary and hybrid Lagrangian-Eulerian models 3 Direct pressure and pressure-marching methods 4 Machine learning 5 Coupled models References Index