Recent Progress on the Transparent Prediction of the Added Resistance and Powering of a Ship in Waves

Recent developments of international regulations on the energy-efficiency and safety of ships and their impact on marine operations and on the environment are driving the ship design and operation to new frontiers. In this context, the accurate prediction of the added resistance of a ship in seaways became a research subject of priority. Considerable effort was devoted by global researchers to the development of new methods to meet the urgent demand of the industry. Among these new methods, the SHOPERA-NTUA-NTU-MARIC (SNNM) method (Liu & Papanikolaou, 2020) was validated by the 29th ITTC Specialist Committee on Ships in Operation at Sea with satisfactory results, demonstrating a broader applicability and higher accuracy than other comparable methods (Wang et al., 2021). Thereafter, it was adopted in the ITTC recommended procedures for analyzing sea trial results and the IMO guidelines for the determination of the minimum propulsive power in adverse condition. In addition to highlighting the features of the SNNM method, this paper will discuss the challenges in improving the method and recent progresses. A new form of empirical diagrams is presented for practical uses.