REEF3D::CFD

Overview |  Applications | Scientific References

Overview

REEF3D::CFD is an open-source CFD model that solves the three-dimensional Navier-Stokes equations. From the start, the focus of this model was to solve complex free surface dynamics through two-phase flow interface capturing. In order to ensure high levels of accuracy while maintaining robustness, REEF3D::CFD is designed on a staggered rectilinear grid. This results in tight pressure-velocity coupling, crucial for stable two-phase flow modeling with its significant density and pressure jumps across the interface.This aspect comes especially into play when modeling waves, where REEF3D’s implementation avoids any form of spurious air flow over the wave free surface. The rectilinear mesh enables the use of high-order conservative finite differences for the discretization of the governing equations. As a result, a relatively coarse mesh can be used when using REEF3D::CFD as a numerical wave tank. A potential loss of flexibility due to the mesh arrangement is avoided through the immersed boundary treatment for complex solid geometries. Mesh generation is performed in the accompanying open-source software DIVEMesh. This pre-processing tool handles solid geometries from STL files, bed interpolation from measured data points, domain decomposition and hydrodynamics coupling. The source code is written in modular C++, enabling straightforward expansion and maintenance of the model. The unique characteristics of REEF3D::CFD are:

  • High-order discretization in space (5th-order WENO)
  • High-order discretization in time (3rd-order TVD Runge-Kutta)
  • Full Parallelization with domain decomposition and MPI
  • Geometric multigrid preconditioned CG-solver (hyper) for efficient solution of the pressure Poisson equation
  • Complex free surface modeling with the level set method
  • Immersed boundary for complex solids
  • Modular C++ for straightforward expansion and maintenance of the model

The flow solver can be used together with the following multiphysics solvers:

  • 6DOF algorithm for floating bodies
  • Mooring line dynamics
  • Static and dynamic net modeling
  • Sediment transport
  • Pollutant transport
  • Heat transfer
  • Turbulence modeling: RANS & LES
  • Porous Media: VRANS
  • Non-Newtownian Rheology
  • Wave generation with a rich library of wave theories
  • Hydrodynamics coupling (HDC) with REEF3D::FNPF

Applications

Breaking Wave Impact on a Jacket Structure

Floating Offshore Wind

Aquaculture Structure in Irregular Waves

Moored Ship Hydrodynamics

Hydropower Plant: Spillway Modeling

Hydro-environmental Modeling: Fish Passage

Sediment Transport: Local Seawall Scour

Sediment Transport: Local Pipeline Scour

Scientific References

a selection of relevant papers covering the different aspects of REEF3D::CFD, the collection of all papers including post-prints can be found under Publications

Bihs H., Kamath A., Alagan Chella M., Aggarwal A., Arntsen Ø.A. (2016)
A New Level Set Numerical Wave Tank with Improved Density Interpolation for Complex Wave Hydrodynamics, Computers & Fluids, Vol. 140, pp. 191-208, DOI: 10.1016/j.compfluid.2016.09.012, download pdf.

Martin T., Tsarau A., Bihs H. (2020)
A Numerical Framework for Modelling the Dynamics of Open Ocean Aquaculture Structures in Viscous Fluids, Applied Ocean Research, DOI: 10.1016/j.apor.2020.102410, download pdf.

Bihs H., Kamath A. (2017)
A Combined Level Set/Ghost Cell Immersed Boundary Representation for Simulations of Floating Bodies, International Journal for Numerical Methods in Fluids, Vol. 83, Issue 12, pp. 905-916, DOI: 10.1002/fld.4333, download pdf.

Ahmad N., Bihs H., Myrhaug D., Kamath A., Arntsen Ø.A. (2019)
Numerical Modeling of Breaking Wave Induced Seawall Scour, Coastal Engineering, Vol. 150, pp. 108-120, DOI: 10.1016/j.coastaleng.2019.02.008, download pdf.

Alagan Chella M., Bihs H., Myrhaug D., Muskulus M. (2016)
Hydrodynamic Characteristics and Geometric Properties of Plunging and Spilling Breakers over Impermeable Slopes, Ocean Modelling, Vol. 103, pp. 53-72, DOI: 10.1016/j.ocemod.2015.11.011, download pdf.

Kamath A., Alagan Chella M., Bihs H., Arntsen Ø.A. (2016)
Breaking Wave Interaction with a Vertical Cylinder and the Effect of Breaker Location, Ocean Engineering, Vol. 128, pp. 105-115, DOI: 10.1016/j.oceaneng.2016.10.025, download pdf.

Grotle E.L., Bihs H., Æsøy V. (2017)
Experimental and Numerical Investigation of Sloshing under Roll Excitation at Shallow Liquid Depths, Ocean Engineering, Vol. 138, pp. 73-85, DOI: 10.1016/j.oceaneng.2017.04.021.