Ship Motions of Cargo Ship in Stormy Condition at Actual Sea - Analysis and Estimation of Ship Motions and Wave Properties due to Onboard Data

It is inevitable to maintain the safety and efficiency in the maritime transportation. Especially, the steep rise of crude oil price requires shipping companies to minimize fuel consumption more than ever. Weather routing services are focused on shipping companies with international transportation. However, there are still many problems on accuracies of current models, such as sea forecasts or slow down due to ship motions. It is the reason why those continuous databases, for example, ship motions, navigation or engine parameters, or sea conditions, are not enough accumulated to develop weather routing models. In this study, those databases have been observed for a couple of years in a 20,000DWT class bulk carrier in worldwide voyages. Some new relations can be known about ship motions, slow down, or wave conditions. The verification of ship motions and waves is carried out here with observed databases and numerical simulations of frequency response of ship motions and that of weather and oceanography. Finally, some points are discussed to construct the new methodology of total evaluation of international maritime transportation in the future.