Abstract
In a simulation-based and data-driven engineering approach, open-access met-ocean data sets and open-source simulation tools are critical elements for marine structure designs. In this work, the authors propose a combined approach for down-scale numerical modelling from offshore met-ocean data to wave loads on structures. The large-scale hind-cast database NORA3 and NORA10 from the Norwegian Meteorology Institute (MET) are used as offshore inputs. The open-source spectral wave model SWAN is used to simulate offshore waves in combination with local wind forcing. The spectral modelling results are then used as inputs in the open-source hydrodynamics framework REEF3D. Its fully nonlinear potential flow (FNPF) module REEF3D::FNPF is used for phase-resolving coastal wave propagation and nonlinear transformation simulations. The arbitrary Eulerian-Lagrangian (ALE) method is integrated into the FNPF model for highly efficient multi-body farm-scale force calculations and extreme events identifications. The extreme events are then closely examined using the hydrodynamic coupling (HDC) approach by transferring the flow kinematics from REEF3D::FNPF to the high-fidelity computational fluid dynamics (CFD) model REEF3D::CFD for fluid-structure interaction analysis. The down-scale approach using the open-access met-ocean data NORA3 and open-source numerical tools and techniques SWAN-REEF3D-ALE-HDC (SARAH) leads to the open and efficient preliminary and detailed design procedure: the NORA-SARAH procedure. This article elaborates on the procedure and demonstrates its effectiveness with an example of a navigational signal tower assessment on the Norwegian coast.