HYDRODYNAMIC OPTIMIZATION OF SHIPS WITH RETROFITTED WASP SYSTEMS

Hannes F. Renzsch, Friendship Systems AG, Germany

Fabian Thies, Friendship Systems AG, Germany

Presented at Innov’Sails conference May 2023

ABSTRACT
Wind assisted ship propulsion has the potential to be one of the mainstays of emission reduction of commercial shipping. As it is not feasible to simply replace the fleet in service by newbuilds optimised for wind assisted propulsion, retrofitting WASP systems to existing ships holds great potential. In recent years several ships have been retrofitted in this way, but without taking into account the operation of the hull in yawed / heeled state due to the forces / moments generated by theses WASP systems. Consequently, the efficiency gain from retrofitting WASP systems to existing ships can be maximised by hull modifications of limited extent. In this paper an efficient approach to evaluate potential hull modifications is presented. The approach is based on the prediction of hydrodynamic properties by response surfaces for the entire design range of modification by simulating a limited number of discrete variants. The impact of these modifications is evaluated in a bespoke simulation and optimisation platform taking into account the properties of the WASP system as well as the ships propulsion as well.