Numerical simulation of maximum wave loads and run-up heights on offshore wind turbine foundations influenced by the instability of bichromatic wave groups

• Published in: Marine structures 2019-09, Vol.67, p.102648, Article 102648
• Main Authors: Lin, Yu-Hsien, Lu, Po-Ying, Lin, Chia-Wei
• Format: Article
• Language: English
• Subjects: Bandpass filters; CFD; Coefficients; Columns (structural); Computational fluid dynamics; Computer simulation; Fluid flow; Flumes; Foundations; Hydraulics; Impact force; Instability; Loads (forces); Mathematical models; Model testing; Offshore; Offshore operations; Offshore wind turbine foundation; Stability; Turbine engines; Turbines; Wave groups; Wave load; Wave run-up; Wind power; Wind turbines
• ISSN: 0951-8339; 1873-4170
• DOI: 10.1016/j.marstruc.2019.102648

In this paper, maximum wave loads and run-up heights around the columns of Offshore Wind Turbine (OWT) foundations for different types by adopting a normalized modulation parameter δˆ were preliminarily analyzed. In order to simulate the evolution of modulated wave groups, bichromatic waves were selected and validated by the experimental data of Tainan Hydraulics Laboratory. The accuracy of wave-structure interaction was also examined by comparing with the model tests of wave loads for the jacket support structure in the wave flume. The quasi-static force and the dynamic force would be separated by using the band-pass filter. In terms of the quasi-static force, it can be estimated by the monochromatic wave and be calibrated in the Morison's load formula. By means of the deconvolution method, the maximum force is well calculated for further obtaining the impact coefficient. The impact coefficients subject to δˆ for different OWT foundations were also summarized. Meanwhile, the normalized run-up heights around the columns of OWT foundations would be discussed qualitatively and quantitatively. Eventually, the impact coefficient and the normalized run-up height would be discussed according to the variation of the curling factor in different wave conditions. •A normalized modulation parameter δˆ were preliminarily analyzed to discuss maximum wave loads and run-up heights for different types of offshore wind turbine foundations.•Bichromatic wave groups were executed to realize the influence of period difference on the fluid-structure interaction.•The tripod foundation is prone to facing the maximum impact coefficient CI, whereas the jacket support structure tends to encounter the minimum impact coefficient CI.