TABLE OF CONTENTS The economic factor is of prime importance in designing a merchant ship. An owner requires a ship which will give the best possible returns for the owners initial investment and running costs. This means that the final design should be arrived at taking into account not only present economic considerations, but also those likely to develop within the life of the ship.
With the aid of computers it is possible to make a study of a large number of varying design parameters and to arrive at a ship design which is not only technically feasible but, more importantly, is the most economically efficient.
The initial design of a ship generally proceeds through three stages: concept; preliminary; and contract design. The process of initial design is often illustrated by the design spiral (Figure 1.1) which indicates that given the objectives of the design, the designer works towards the best solution adjusting and balancing the interrelated parameters as the designer goes.
A concept design should, from the objectives, provide sufficient information for a basic techno-economic assessment of the alternatives to be made. Economic criteria that may be derived for commercial ship designs and used to measure their profitability are net present value, discounted cash flow or required freight rate. Preliminary design refines and analyses the agreed concept design, fills out...
