Development and Validation of Real-Time Hybrid Model Testing Framework for Aerodynamic Simulation of Floating Wind Turbines

Abstract Globally, there is a surge in offshore wind farms, with Floating Offshore Wind Turbines (FOWTs) becoming the focal point of research and industry investment. To ensure the accuracy of the numerical model and the operation safety of FOWTs, it is crucial to conduct model test. This will provide a comprehensive understanding of the complex structural behavior of FOWTs under the combined influence of wind and wave loads. However, the process is complicated due to Reynolds-Froude scaling incompatibilities. The reproduction of aerodynamic loads of FOWTs in wave basin model tests is complex because the aerodynamic loads are dominated by Reynolds similarity. To address this issue, various strategies have been employed, including the use of a tuned actuator disk or a redesigned rotor to achieve the correct scaled thrust at low Reynolds numbers. However, these methods only ensure the similarity of mean thrust under some certain wind velocities, while some important properties of floating wind turbine are still out of reach, such as aerodynamic damping and wind turbine control strategy. In this paper, a Real-Time Hybrid Testing (RTHT) framework is introduced to integrate aerodynamic thrust during wave basin model tests. The feasibility and fidelity of the proposed RTHT framework are verified by using a Pitch-mode Modeling System (PMMS) of FOWT so that the construction and commission of RTHT framework could be conducted on land and modified. The PMMS can accurately simulate the aerodynamic load, inertial load, and hydrostatic restoring moment of a FOWT. Additionally, the RTHT system is calibrated and enhanced by examine the correlation between experimental measurements and simulation results. The results indicate that the proposed RTHT framework, based on PMMS, can effectively reproduces the aerodynamic load of FOWT under different wind conditions and control regimes in a low latency.