OpenFOAM is an open source code focused on computational modeling of fluid mechanics, which works on Linux and is programmed in C++. It also has a lot of applications and solvers which are very useful to simulate several phenomenons and engineering problems. It is compatible with other software and has discretization methods included. This code is versatile to simulate different scenarios.
In this opportunity we will present the best scientific articles to learn about the OpenFOAM capacities in the coastal engineering field.
Note: All the information on this post belongs to the corresponding authors of each scientific article.
1. Numerical investigation of wave–structure interaction using OpenFOAM
Authors: L.F.Chen, J.Zang, A.J.Hillis, G.C.J.Morgan, A.R.Plummer.
The present work is focused on the assessment of how OpenFOAM performs when applied to non-linear wave interactions with offshore structures for ranges of wave conditions. New modules have been further extended to advance the wave generation and wave absorbing capabilities of the code. The numerical results for wave interactions with a vertical surface piercing cylinder have been compared with physical experiments performed at Danish Hydraulic Institute (DHI). Comparisons between the numerical results and the measured data for three regular waves and four focused wave groups, have indicated that OpenFOAM is very capable of accurate modelling of nonlinear wave interaction with offshore structures, with up to 4th order harmonic correctly captured. Moreover, by using the cresttrough phase-based separation method, we can reproduce harmonic structure in the wave loading on the structure and free surface elevations.
2. On the use of OpenFOAM to model oscillating wave surge converters
Authors: Pál Schmitt, BjörnElsaesser.
The computational fluid dynamic (CFD) toolbox OpenFOAM is used to assess the applicability of Reynolds-averaged Navier–Stokes (RANS) solvers to the simulation of oscillating wave surge converters (OWSC) in significant waves. Simulation of these flap type devices requires the solution of the equations of motion and the representation of the OWSC's motion in a moving mesh. A new way to simulate the sea floor inside a section of the moving mesh with a moving dissipation zone is presented. To assess the accuracy of the new solver, experiments are conducted in regular and irregular wave traces for a full three dimensional model. Results for acceleration and flow features are presented for numerical and experimental data. It is found that the new numerical model reproduces experimental results within the bounds of experimental accuracy.
3. Numerical wave tank study of extreme waves and wave-structure interaction using OpenFoam
Authors: Zheng Zheng Hu, Deborah Greaves, Alison Raby.
In the present work, the open source Computational Fluid Dynamics (CFD) package-Open Field Operation and Manipulation (OpenFoam®) is used to simulate wave-structure interactions and a new wave boundary condition is developed for extreme waves. The new wave boundary condition is implemented for simulation of interaction with a fixed/floating truncated cylinder and a simplified Floating Production Storage and Offloading platform (FPSO) and results are compared with physical experiment data obtained in the COAST laboratory at Plymouth University. Different approaches to mesh generation (i.e. block and split-hexahedra) are investigated and found to be suitable for cases considered here; grid and time convergence is also demonstrated. The validation work includes comparison with theoretical and experimental data. The cases performed demonstrate that OpenFoam® is capable of predicting these cases of wave-structure interaction with good accuracy (e.g. the value of maximum pressure on the FPSO is predicted within 2.4% of the experiment) and efficiency. The code is run in parallel using high performance computing and the simulations presented have shown that OpenFoam® is a suitable tool for coastal and offshore engineering applications, is able to simulate two-phase flow in 3D domains and to predict wave-structure interaction well.
4. Performance assessment of OpenFOAM and FLOW-3D in the numerical modeling of a low Reynolds number hydraulic jump
Authors: Arnau Bayon, Daniel Valero, Rafael García-Bartual, Francisco José Vallés-Morán, P. Amparo Lépez-Jiménez.
A comparative performance analysis of the CFD platforms OpenFOAM and FLOW-3D is presented, focusing on a 3D swirling turbulent flow: a steady hydraulic jump at low Reynolds number. Turbulence is treated using RANS approach RNG k-ε. A Volume Of Fluid (VOF) method is used to track the airewater interface, consequently aeration is modeled using an EulerianeEulerian approach. Structured meshes of cubic elements are used to discretize the channel geometry. The numerical model accuracy is assessed comparing representative hydraulic jump variables (sequent depth ratio, roller length, mean velocity profiles, velocity decay or free surface profile) to experimental data. The model results are also compared to previous studies to broaden the result validation. Both codes reproduced the phenomenon under study concurring with experimental data, although special care must be taken when swirling flows occur. Both models can be used to reproduce the hydraulic performance of energy dissipation structures at low Reynolds numbers.
5. Simulating coastal engineering processes with OpenFOAM
Authors: Pablo Higuera, Javier L. Lara, Inigo J. Losada
In the present work, the OpenFOAM® newly developed wave generation and active absorption boundary condition presented in the companion paper (Higuera et al., submitted for publication) is validated. In order to do so the simulation of some of the most interesting physical processes in coastal engineering is carried out and comparisons with relevant experimental benchmark cases presented. Water waves are found to be generated realistically and agreement between laboratory and numerical data is very high regarding wave breaking, run up and undertow currents.
6. Realistic wave generation and active wave absorption for Navier–Stokes models application to OpenFOAM®
Authors: Pablo Higuera, Javier L. Lara, Inigo J. Losada.
The present paper and its companion (Higuera et al., 2012) introduce OpenFOAM® as a tool to consider for coastal engineering applications as it solves 3D domains and considers two-phase flow. In this first paper, OpenFOAM® utilities are presented and the free surface flow solvers are analysed. The lack of specific boundary conditions for realistic wave generation is overcome with their implementation combined with active wave absorption. Wave generation includes all the widely used theories plus specific piston-type wavemaker replication. Also standalone active wave absorption implementation is explained for several formulations, all of which are applicable to 3D cases. Active wave absorption is found to enhance stability by decreasing the energy of the system and to correct the increasing water level on long simulations. Furthermore, it is advantageous with respect to dissipation zones such as sponge layers, as it does not increase the computational domain. The results vary depending on the theory (2D, Quasi-3D and 3D) but overall performance of the implemented methods is very good. The simulations and results of the present paper are purely theoretical. Comparisons with laboratory data are presented in the second paper (Higuera et al., 2012).
7. Three-dimensional interaction of waves and porous coastal structures using OpenFOAM®.
Part I: Formulation and validation and Part II: Application
Authors: Pablo Higuera, Javier L. Lara, Inigo J. Losada
Part I: In this paper and its companion (Higuera et al., 2014–this issue), the latest advancements regarding Volumeaveraged Reynolds-averaged Navier–Stokes (VARANS) are developed in OpenFOAM® and applied. A new solver, called IHFOAM, is programmed to overcome the limitations and errors in the original OpenFOAM® code, having a rigorous implementation of the equations. Turbulence modelling is also addressed for k- and k-ω SST models within the porous media. The numerical model is validated for a wide range of cases including a dam break and wave interaction with porous structures both in two and three dimensions. In the second part of this paper the model is applied to simulate wave interaction with a real structure, using an innovative hybrid (2D– 3D) methodology.
Part II: This paper and its companion Higuera et al. (2014–this issue) introduce the formulation of Volume-Averaged Reynolds-Averaged Navier–Stokes (VARANS) equations in OpenFOAM® to simulate two-phase flow through porous media. This new implementation, so-called IHFOAM, corrects the limitations of the original OpenFOAM® code. An innovative hybrid methodology (2D–3D) is presented to optimize the simulation time needed to assess the three-dimensional effects of wave interaction with coastal structures. The combined use of a 2D and a 3D model enables the practical application of the 3D VARANS code to simulate real cases, contributing to a significant speed-up. This is highly convenient and especially suitable for non-conventional structures, as it overcomes the limitations inherent to applying semi-empirical formulations out of their range or 2D simulations only. A detailed study of stability and overtopping for a 3D porous high-mound breakwater at prototype scale subjected to oblique irregular (random) waves is carried out. Pressure around the caissons, overtopping discharge rate and turbulent magnitudes are presented in three dimensions. The mean pressure laws present a high degree of accordance with the formulation provided by Goda–Takahashi. Furthermore, local effects due to three-dimensional processes play a significant role, especially close to the breakwater head.