FLETTNER ROTORS PERFORMANCE AND INTERACTION EFFECTS ON THE MARIN HYBRID TRANSITION COASTER

In the context of ship design, including wind propulsion, knowing the aerodynamic performance of a ship and its wind propulsors is essential. In the literature, the performance of wind propulsors is generally derived from wind tunnel test data, full scale tests or CFD. Those experimental or numerical databases are often omitting the interactions with the ship and its superstructures and atmospheric boundary layer. In this research, a numerical approach using RANS simulations is developed to estimate the effects of the interaction between the MARIN Hybrid Transition Coaster (MHTC) and its three Flettner rotors. In order to assess the effects of these interactions, the performance of a Flettner rotor positioned on the deck of the vessel is compared to the performance of a free standing Flettner rotor. Large interaction effects are found to depend on the apparent wind angle. Accounting for these interactions is essential. A model is proposed to correct the performance of a free standing Flettner rotor to the performance of a rotor on the deck of the vessel. In addition the effects of multiple wind propulsors are studied in relation to this model.