There is an ever-increasing interest to analyze problems related to the dynamics of fluids and their interactions with fixed or floating offshore structures. Continued technological advances in computer power have enabled the development of novel numerical methods and their application to analysis and engineering design; this has improved our understanding of many complex problems that were unsolved before. The increasing demands for harnessing marine renewable energy, and the challenges from more extreme weather due to climate change add difficulties and opportunities to this field. This Special Section aims to highlight recent efforts in the development of advanced numerical methods as well as their applications to marine hydrodynamics for a wide range of applications.

There is a wide-ranging set of papers included in this Special Section. One study by Swain and coauthors deals with the simulation of a tandem flapping foil following an elliptical trajectory, focusing on aerodynamic characteristics and propulsive efficiency. It also offers insights into the development of biomimetic propulsion devices capitalizing on propulsive efficiency and the effect of the wake vortex. Another study by Toni and de Arruda Martins presents a parallelized implementation of an element-by-element architecture for the structural analysis of flexible pipes using finite macroelements. A few different synchronization algorithms are developed, and their scalability is assessed. Significant gains in simulation time and memory consumption are demonstrated. Oblique wave scattering by a thick vertical rectangular wall with a gap in the presence of ice cover is the subject of another study by Chakraborty and Samanta. A mathematical solution to this problem employs the boundary element method and a multi-term Galerkin approximation with Gegenbaurer polynomials as basis functions. The authors suggest that the mathematical technique and analysis used can be applied to various other wave-structure interaction problems in marine engineering. An artificial intelligence (AI) method using a software-in-the-loop concept is employed by Chen and Hu to study the dynamic response of floating offshore wind turbines (FOWTs). Key disciplinary parameters are considered in a reinforcement learning algorithm where basin experimental data of a spar-type FOWT are used for training. The authors suggest that one can derive a deeper understanding of the dynamic response of the turbine system and also offer options for validation studies.

Additional studies rounding out this Special Section address a comparative study of the flow-induced vibration of a circular cylinder attached with front and/or rear splitter plates at a low Reynolds number of 120 (by Tang and coauthors); the modal analysis of a monopile-supported offshore wind turbine (by Pezeshki and coauthors); and a study of oblique wave diffraction by a bottom-standing thick barrier and a pair of partially immersed barriers (by Sarkar and De).