Propulsion Enhancements for a Greener Environment

In anticipation of new regulations ruling energy efficiency on board ships and also in view of the actual development of oil prices, fuel economy is more than ever of prime importance to all commercial ship operations. Improving propulsive efficiency, particularly through the application of add-on Propulsion Improvement Devices (PIDs), appears to be an option not only for newly-designed vessels but also as retro-fit for existing ships. Assessing the potential benefits of PIDs, however, remains a crucial issue. While the use of CFD for hullform optimisations with respect to resistance improvements represent the state-ofthe-art today, more advanced numerical modelling techniques are now applied to simulate a complete numerical propulsion test and to analyse the effect of different PIDs. Using HSVA‟s in-house RANS code FreSCo + , the effects of fins and a duct on a tanker hull and pre-swirl stator on a container vessel have been analysed after validating the code for a common test case. The potential of the devices considered has been evaluated.