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In this paper, we develop the Virtual Source Method for simulation of incompressible and irrotational fluid flows. The method is based upon the integral equations derived by using Green's identity with Laplace's equation for the velocity potential. The velocity potential within the fluid domain is completely determined by the potential on a virtual boundary located above the fluid. This avoids the need to evaluate singular integrals. Furthermore, the solution method developed here is meshless in space in that discretisation is in terms of the spectral components of the solution along this virtual boundary. These are determined by specifying non-linear boundary conditions on the velocity potential on the air/water surface using Bernoulli's equation. A fourth-order Runge-Kutta procedure is used to update the spectral components in time. The method is used to model high-amplitude standing waves and sloshing. Results are compared with theory where applicable and some interesting physical phenomena are identified. [ABSTRACT FROM AUTHOR]

We develop a free surface tracking solver for numerical simulation of unsteady irrotational fully non-linear water waves in a freely available open-source computational fluid dynamics toolbox OpenFOAM ®-Ext, which is community-driven release of OpenFOAM ®. The solver is based on the solution of the Laplacian of the velocity potential with moving free surface. The free surface is tracked by solving the kinematic boundary condition based on the normal flux out of the surface. We also develop the necessary boundary conditions for the realistic wave generation at inlet and the absorption boundary condition at the outlet boundary. To avoid numerical instability, a 5-point smoothing technique is used to smooth the free surface elevation. Solution of Laplace's equation for the velocity potential, the non-linear free surface boundary conditions, the wave generation and the absorption boundary conditions are all not part of the standard OpenFOAM ® distribution. The potential flow solver is able to simulate large amplitude standing and progressive waves. We validate the solver by comparing the numerical results with analytical results for second order standing waves, and progressive waves with experimental results and satisfactory agreement is found. [ABSTRACT FROM AUTHOR]

In this paper, numerical and experimental study of a simplified Floating Production Storage and Offloading (FPSO) in extreme free surface waves is presented. The physical model experiments are carried out in Plymouth University's COAST Laboratory ocean basin and the numerical simulation is based on the open source Computational Fluid Dynamics (CFD) package Open Field Operation and Manipulation (OpenFOAM®). The FPSO is either fixed or moored with Six Degrees of Freedom (6DoF) motion in the waves. The Dynamic Fluid Body Interaction (DFBI) model is employed to calculate the forces and moments including the external forces from connection such as a spring of the moored FPSO. Comparison of key parameters, including the wave run up, pressure, FPSO motion and mooring load are drawn between the experiment and the OpenFOAM results and found to agree reasonably well. [ABSTRACT FROM AUTHOR]

The article discusses research which investigated the numerical modelling of unidirectional focused wave groups for freak wave generation. Topics discussed include the use of other numerical models for the iterations of correcting the input signal Open Field Operation and Manipulation (OpenFOAM), numerical wave tank in Simulating Waves Till Shore (SWASH) and comparison with experimental results.

The article discusses research which examined the survivability of a point-absorbing wave energy converter (WEC) model in extreme wave tests with focused waves embedded in regular wave backgrounds. Topics discussed include the floats used in the study, extreme wave events derived from site-specific historical wind and wave data and the identification of the peaks and troughs in the irregular waves.

The article discusses research which investigated the interaction between a simplified floating production storage and offloading (FPSO) and focusing waves. Topics discussed include the FPSO either fixed or moored in the waves and use of the fully nonlinear potential theory (FNPT)-based Quasi Arbitrary Lagrangian Eulerian Finite Element Method (QALE-FEM).

The article discusses research which explored the development of an interface-tracking algorithm to address the two-dimensional time dependent free surface flows. Topics discussed include solving a mixed boundary value problem to obtain the velocity potential and the use of open-source computational fluid dynamic toolbox, Open Field Operatrion and Manipulation (OpenFOAM).

The article discusses research which investigated the wave impact on a truncated vertical wall. Topics discussed include the numerical simulation based on the Open Field Operation and Manipulation (OpenFOAM), an open source Computational Fluid Dynamics (CFD) package and comparison of the total impact force on the rigid wall and elastic wall.

The article focuses on a study which described a numerical approach to create a decision-making tool patterned after the three-dimensional regional ocean modeling system for planning tidal current turbine (TCT) arrays. Validation of the proposed turbine modeling methods was done by conducting a model-data comparison between physical scale model and numerical model results. The method proposed reproduced an experimental test case from a momentum and a turbulence point of view.

The article discusses a study that investigated the hydrodynamic characteristics of wave energy converters. According to the article, simulation of wave interaction with a semi-submerged chamber was performed using a numerical method based on a two-phase level set with the global mass correction. A comparison of focused wave results with numerical and physical experiment results is presented.