Comparison of Seakeeping performance of the two super yachts of 53 and 46 m in length

Abstract

General Seakeeping qualities of the projected 53-meter and 46-meter motor yachts have been determined by means of theoretical calculations. With the help of a Two-dimensional source distribution program and a linear strip theory method various ship motions and acceleration as well as different extreme effects like deck wetness and bottom slamming were derived for the vessel running in irregular short-crested seaways. Thereby the full ranges of relative course angels and ship speed up to 16 knots have been taken into consideration. In this study two operational areas (Mediterranean and Aegean Sea) and three sea ways conditions (sea State 3, 4 and 5) were investigated which feature significant wave height in the range of 0.88 m and 3.25 m. The outcome of the theoretical study was checked against various performance criteria. The compliance of the projected motor yacht with limiting criteria is illustrated in the form of polar diagrams. Besides this, the seakeeping characteristics of the vessel (ship motion and extreme seakeeping effects) are represented in the form of Cartesian diagrams for all combination of seaway condition, relative course angle and ship speed. In sea State 3 conditions the projected vessels can run without restriction in both areas of operation. In contrast, some performance criteria are exceeded in sea State 4 while the operations of the yachts are restricted in sea State 5 by at least one performance criteria.