Optimal Thruster Location for Increased DP Operability

The location of thrusters on an offshore unit is not a primary design driver. However, the location of these devices along the hull greatly influences the capability and operability of the Dynamic Positioning system and, consequently, the vessel’s consumption. In the early design stage, Dynamic Positioning calculations are usually performed with quasi-static calculations, employing simplified methods to assess the environmental loads needed for determining the equilibrium. A process based on genetic algorithms has been developed to find the optimal thruster location on an offshore vessel by maximising the operability in a reference working area. The process handles a double optimisation problem, as, for each step of the location optimisation, multiple optimisations should be performed to solve the Dynamic Positioning problem. The process is here tested on a reference offshore ship, highlighting that the optimised configuration has higher operability than the original one for the sea area of interest.