Ship as a buoy for phase-resolved ocean wave field reconstruction and forecast

This study introduces a novel method for phase-resolved ocean wave field reconstruction and forecast using measured ship responses. Starting with a time sequence of these measured responses, we first derive a preliminary coarse estimation of the phase-resolved ocean wave field through the spectrum analysis, pre-estimated transfer functions, and linear wave theory. Subsequently, we employ a data assimilation-based computational framework that couples the high-order spectral method, a Cummins-equation-based ship dynamic model, and the ensemble Kalman filter to further improve the accuracy of the phase-resolved ocean wave field and ship motion results. Numerical experiments demonstrate that this integrated method not only achieves precise phase-resolved ocean wave field reconstruction but also refines ship response results compared to the measurements. The final analysis results for both wave field and ship motion can be used as initial conditions for a future forecast, which will be much more accurate than otherwise (e.g., using measurement as initial condition).