Deriving mathematical manoeuvring models for bare hull ships using viscous-flow calculations

In the present paper, the work conducted by the author regarding efficient determination of hydrodynamic coefficients for manoeuvring ships within the manoeuvring work package of the EU project VIRTUE is presented. Based on various viscous-flow calculations for steady drift motion, steady yaw motion and combined drift/yaw motion, a mathematical model for the bare hull forces and moments is derived. The results show that using accurate viscous-flow calculations, a considerable improvement in the prediction of the forces and moments on ships compared to conventional empiric methods published in open literature is obtained. Two hull forms are considered in this study. The first ship is the Hamburg Test Case (HTC), a single-screw ship. The second ship is the MARIN LNG carrier with twin gondolas.