Description of hull form and evaluation of ship performance (3rd Report)

Abstract

Experienced ship designers have been done the optimization of hull form and/or improvements of propulsive performance in the performance design procedure using their metaphysical information and analogized knowledge-process abilities based on their long-continued experiences. It may have been because that there have not been any formulations which make it possible to describe and evaluate the frame line configuration explicitly and quantitatively.In the second paper, the authors introduced a method for expressing and describing the frame line configuration using the Fourier Descriptors (FD), and showed that it is possible to describe almost all frame lines of ship's aft body and their small and fine changes. They also showed that FD is an appropriate method to express the relation between frame line configuration and self-propulsion factors.In the present paper, they discuss the effects of fine changes of frame line on the changes and improvements of self-propulsion factors (1-w) using the Fourier Descriptors. They show that the process of determining frame line configuration and its fine changes for improvements of self-propulsion factors that have been done intuitively and metaphysically by experienced ship designers are quite reasonable.