Integrated Design of Asymmetric Aftbody and Propeller for an Aframax Tanker to Maximize Energy Efficiency

AuthorsJie Dang (MARIN), Chen Hao (GSI, China), Luis Rueda (MARIN), Harry Willemsen (MARIN)
Conference/JournalFourth International Symposium on Marine Propulsors (SMP), Austin, Texas
DateMay 31, 2015

With the implementation of the EEDI, energy saving and emission reduction of ships, especially merchant ships, become more and more important. To achieve high efficiency and low emissions, recently Energy Saving Devices (ESDs) have been re-studied and installed to many ships, both new buildings and also retrofits. Various ESDs, including new concepts, have been tested in model scale and large improvements on energy efficiency have been confirmed. However due to the fact that most ESDs are fitted in the wake field, the performance of the ESDs is influenced by scale effects. For the operators, the fouling and the structure integration of the ESD's with the hull are the important issues to make decisions on applying ESDs to their ships.Distinguished from the ESDs where extra 'appendages' have to be added in front of and/or behind a propeller, an asymmetric aftbody can also change the flow towards the propeller without appendages. The wake with pre-swirl generated by an asymmetric aftbody is in general more uniform than that by an ESD (such as a pre-stator with finite blades) and with almost no penalty on the ship's resistance. By integrating a propeller, a ship with asymmetric aftbody can be designed so that the hull-propeller interaction is optimized for its total propulsive effic

Tags
sustainable propulsioncfd developmentcfd/simulation/desk studiesresistance and propulsionpropulsionenergy saving