CCP-WSI Blind Test Series 2: A Nonlinear Froude-Krylov Modelling Approach. Issue 2 (10th June 2020)

• Record Type: Journal Article
• Authors: Giorgi, Giuseppe
• Is Part Of: Proceedings of the Institution of Civil Engineers. Volume 173:Issue 2(2020:Jun.)
• Page Start: 1
• Page End: 32
• Publication Date: 2020-06-10
• Subjects: Nonlinear Froude-Krylov -- Nonlinear modelling -- Nonlinear kinematics; Mechanics, Applied -- Periodicals; Structural engineering -- Mathematics -- Periodicals; Engineering mathematics -- Periodicals; 624.17
• DOI: 10.1680/jencm.19.00029
• Languages: English
• ISSNs: 1755-0777

Abstract

Abstract : One of the essential stepping stones for reaching economic viability and industrial feasibility of the wave energy conversion sector is the effectiveness of the device design, which is dependent, among others, to the accuracy of mathematical models used for development. Despite being more than 45 years old, modelling is not mature yet and there is still a clear lack of standardization of modelling techniques, and a need for increasing confidence in hydrodynamic models. The objective of the the Collaborative Computational Project in Wave Structure Interaction (CCP-WSI) is to critically compare and evaluate various different modelling techniques, under the same shared experimental conditions, and using clearly pre-defined metrics. This paper details a contribution implementing, in a computationally efficient way, nonlinear Froude-Krylov forces and nonlinear kinematics. The goal is to define a medium-high fidelity model, higher than linear models and comparable with nonlinear models, but able to compute at a small fraction of the computational time typically required by fully-nonlinear models. The case study considers survivability-like wave conditions, represented by three steep focused waves, which are particularly challenging to be modelled using partially-nonlinear potential theory-based mathematical models. Despite a poor representation in the pitch and surge response, a good agreement with experimental heave response and mooring load is found, at small computation time (compared to fully-nonlinear models), close to real-time computation.