Pre-Swirl Fins Design for Improved Propulsive Performances

Pre-swirl ns-based Energy Saving Devices (ESDs) have been designed to improve the propulsive performances of a twin-screw ship. To achieve this aim, a combined BEM/RANS method for selfpropulsion prediction is required. The approach is included in a framework for a design by optimization, where systematic variations of the ESD geometry have been used to explore the design space and maximize the energy-saving eect of the device. The results show encouraging improvements that reach a promising energy-savings of 2.9%.