Advancing floating offshore wind turbine construction from the perspective of wet towing using a tugboat with autonomous control

The abundant offshore wind energy resources present extensive development opportunities for wind turbines, with the safety and reliability of transportation operations serving as essential prerequisites for ensuring their successful deployment and long-term operation. This research develops a constant parameter time-domain model (CPTDM) for the towing operation simulation of an IEA 15MW floating offshore wind turbine (FOWT) foundation in waves based on a state space model (SSM) for the first time and integrates the lumped mass method. To validate the accuracy and efficiency of CPTDM, three innovative towing simulation methods are proposed in the hydrodynamic analysis software AQWA. Through the viscous damping correction by the computational fluid dynamics (CFD) method, hydrodynamic coefficients correction, time-domain analyses of towing system motion responses and cable tensions under different wave environments, and encounter frequency verification, the consistency of the dynamics comparison verification results between CPTDM and AQWA in time-domain analyzes is over 90%, and the efficiency of CPTDM improved approximately 50%. Eventually, an optimal simulation method, a high-fidelity numerical model and a recommended towing speed range for a FOWT are presented in this study, aiming to provide valuable guidance for the actual towing construction of a FOWT.