Design Evaluation of an Energy Saving Device to Minimize Ship’s Resistance

Reduction of emissions and gain of fuel efficiency have always been a desirable goal to be achieved in the shipping industry. Several energy-saving devices have been proposed and implemented on new-built ships as well as existing fleets over the past few decades. However, most of the studies are focused on seagoing ships, with hardly any studies available on inland ships. In this present study, a benchmark hull, JBC, without and with WED (wake equalizing duct) is first validated with experimental results. A verification study is performed for the assessment of numerical uncertainty. The numerical analyses are conducted in OpenFOAM. The study is further elaborated through a stepped design process by altering some key parameters associated with the sectional shape of the duct to achieve improvement in results. The result shows maximum reduction in resistance up to 2 %. To avoid the complexity associated with the propeller, the study is limited to hulls with ESD only. Finally, the selected optimal WED is implemented in an existing inland bulk carrier and the result shows a significant reduction in resistance up to 5 %. The study reveals that the effect of energy-saving is pronounced in fuller ships with compact WED, particularly at low speeds.