Abstract: The FP7 project GRIP deals with Energy Saving Devices (ESDs). These are devices placed in front, or aft of the propeller with the aim to reduce the fuel consumption of the vessel. VICUS has worked on a hydrodynamic design procedure and had the opportunity to apply it to a validation vessel: a new-build handymax Bulk carrier by Uljanik shipyard in Croatia. VICUS has selected a downstream device, named Rudder Bulb, for this application case: it is positioned aft of the propeller and allows for a reduction of the rotational energy of the outflow. Two other partners within GRIP have also been developing their own methodology for the hydrodynamic design of an ESD. MARIN have worked on a Pre-Duct and HSVA on a Pre-Swirl Stator. Each partner has designed its ESD according to its own procedure for the Uljanik bulk carrier. From these three ESD, a cross check was carried out in order to select the device that will be manufactured on the full scale vessel. HSVA’s Pre-Swirl Stator was chosen and was been installed on the ULJ vessel. Full scale trials were carried out on the vessel, giving satisfactory results (see (Xing-Kaeding ISP (2015)) and (Hasselaar and Xing-Kaeding, ISP (2015))). In this paper, only the procedures employed by VICUS for the Rudder Bulb design as well as the results of the cross check are presented.
Keywords: Energy saving device, ESD, pre-swirl stator, PSS, pre-duct, rudder bulb, CFD, RANS-BEM coupling, frozen rotor, sliding interface, full scale, model scale, hub vortex, cavitation reduction, parametric model
