Evaluation of Numerical Methodologies and Physical Effects on a Performance-Scaled Floating Offshore Wind Turbine Rotor

Evaluation of Numerical Methodologies and Physical Effects on a Performance-Scaled Floating Offshore Wind Turbine Rotor

Offshore Technology Conference

10.4043/32153-MS

http://dx.doi.org/10.4043/32153-ms

Gijs Bouman, Jorrit-Jan Serraris, Chin Lee Lim, Xiuqing Xing, Chang Wei Kang, Xiaoqin Zhang, Harish Gopalan, Vinh Tan Nguyen, Xuan Liu, Venugopalan S.G. Raghavan, Chien Sheng Poh, Kai Yu

Mechanical Engineering

24 April 2023

Bouman, G., Serraris, J.-J., Lim, C. L., Xing, X., Kang, C. W., Zhang, X., Gopalan, H., Nguyen, V. T., Liu, X., S.G. Raghavan, V., Poh, C. S., Yu, K. (2023, April 24). Evaluation of Numerical Methodologies and Physical Effects on a Performance-Scaled Floating Offshore Wind Turbine Rotor. Day 1 Mon, May 01, 2023. https://doi.org/10.4043/32153-ms

Abstract Performing numerical simulations of a scaled-down experimental setup of a floating offshore wind turbine allows for a two-way validation between the two approaches. Furthermore, additional insight in the physical behavior of the system can be obtained by tuning numerical results on experimental measurements, and exploring the results. Numerical simulations of a 10MW floating offshore wind turbine model in a wave basin are performed at model scale using computational fluid dynamics. The performance-scaled turbine is designed to match the Froude-scaled thrust force in a Froude-scaled wind field. Initial results show a discrepancy in calculated turbine thrust and torque results compared with experimental results. Two main challenges are identified: (1) selecting a numerical approach appropriate for the low-Reynolds number flow, and (2) accurately modelling the environmental conditions in the basin. In this paper, a numerical sensitivity study is carried out by varying systematically the turbulence models and inflow conditions. A standard k − ε turbulence model is used, as well as a more extensive γ – Reθ turbulence transition model. Different inflow conditions are set up to model the turbulent jet wind field in the wave basin. It is found that the k-ε turbulence model is unsuitable to match the model test results, while satisfying results are obtained using the γ – Reθ model. Furthermore, it is seen that the turbulent jet inflow is represented well by both a vertical power law profile and a radial profile fitted to wind field measurements, while uniform and tabulated inflow conditions are a poor representation of the experimental conditions. It is concluded that effects from surface roughness, the Reynolds number, the inflow velocity and turbulence distribution must be included in the numerical evaluation.

Publisher Copyright

This research / project is supported by the A*STAR - Industry Alignment Fund – Industry Collaboration Projects (IAF-ICP)
Grant Reference no. : I2101E0003

https://oar.a-star.edu.sg/communities-collections/articles/19818

978-1-61399-974-5

Institute of High Performance Computing