Solitary Wave Propagation Using a Novel Single Fluid Finite Volume Method for Free Surface Gravity Waves

• Published in: Volume 7: CFD and FSI
• Main Authors: Qwist, Jesper Roland Kjærgaard, Christensen, Erik Damgaard
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Society of Mechanical Engineers 2022
• Subjects: Offshore structures; Two phase flow; Numerical modelling; CFD; Numerical Simulations; Finite volume method; Nonlinear waves; Arctic
• Online Access: https://orbit.dtu.dk/en/publications/7c7c198c-7067-4702-aa7f-8a4d644e2e65; https://doi.org/10.1115/OMAE2022-80255; https://backend.orbit.dtu.dk/ws/files/280177896/OMAE2022_80255_25Feb2022_1328_VER005_FINAL_SUBMISSION.pdf

Accurate prediction of wave loads from extreme waves on individual beams in offshore jacket structures are important to ensure the structural integrity. As the load distribution along a beam is strongly tied to the wave kinematics it is crucial to have an accurate prediction of the surface elevation and the velocity field. The open-source CFD code OpenFOAM contains two solution algorithms (interFoam and interIsoFoam), which are used for ocean wave simulations and wave load predictions. The algorithms are often applied using a too coarse spatial discretisation, which violates the assumption of a continuous solution at the free surface. The consequence is inaccurate and unphysical predictions even for propagation of a steady wave. Our recently developed Direct Surface Description (DSD) solution algorithm in OpenFOAM is used to simulate a solitary wave with different cell aspect ratios. The solitary wave case shows that the DSD method provides accurate velocity fields and surface elevations both for square and horizontally elongated cells.