Multi Objective Design of Ships; A Pareto Procedure

Abstract

The design calculations for a displacement type vessel and for a planing hull are done for the main dimensions, starting with a fuel and acceleration criteria. A large number of vessels are simulated with the help of available algorithms in the open literature such as the UBC series for the displacement types. Ship design is continuously changing and new design technologies developed during the last two decades. The method used in this study is to calculate ship resistance and ship motion based on suitable algorithms and on the calculation of dynamic effects such as acceleration, slamming, and added resistance and observe the influence of the principal dimensions on these quantities in a simulation procedure. The design requirements are then used to select a suitable candidate ship. Pareto fronts are obtained for two parameters such as the effective horse power and the acceleration levels. Pareto procedure for design is illustrated for a two parameter design procedure. Possible combination of ship principal dimensions is obtained for the relative importance of the design parameter, as seen by the owner or the designer. Application is then expanded to planing hulls. Many solutions are first obtained in a range of desirable speeds, beam, and dead rise angle. The solutions in the range of planing hull speed ratio are considered. The satisfactory solutions with combined criteria in the Pareto front are tested and studied in some more details. A ‘better’ solution is recommended to the designer. Additional criteria are considered in the selection such as the critical trim angle as constraints etc. © 2021, Springer Nature Singapore Pte Ltd.