Ship maneuvering prediction relies on hydrodynamic derivatives, traditionally obtained through empirical formulations based on hulls built decades ago. A comparison with experimental data revealed a notable discrepancy, particularly for the linear sway velocity derivative (
), where these regression models
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Ship maneuvering prediction relies on hydrodynamic derivatives, traditionally obtained through empirical formulations based on hulls built decades ago. A comparison with experimental data revealed a notable discrepancy, particularly for the linear sway velocity derivative (
), where these regression models inadequately capture the behavior of modern hulls. To overcome this limitation, a novel approach is proposed, in which 690 virtual static drift tests were conducted across a systematic series of 115 modern hull forms, parametrically generated in the Grasshopper platform and thus benchmarked against seven vessels. This extensive numerical dataset enabled the development of an updated regression formulation for
, which was grounded in key geometric parameters and incorporated specific terms related to the bow and stern shapes. The results obtained by the CFD-based method were compared with those obtained experimentally, confirming the high fidelity of this approach, yielding a maximum relative error of only
for the sway linear velocity derivative. Crucially, when this proposed empirical formula was integrated into a mathematical model (MM-TPN) to predict a ship’s trajectory, it demonstrated substantial improvement by reducing the absolute relative error in standard maneuvers from
to
compared with traditional methods used to describe the
. Furthermore, an extensive discussion regarding the regression model was conducted, leading to the establishment of the drift angle threshold that invalidates the linear theory (set at
for blunt hulls and
for slender hulls). A comprehensive three-step validation process, encompassing the
of the virtual static drift tests, validation of the derived maneuvering coefficient, and validation through standard maneuvers employing the novel approach proposed here, was fully executed.
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