STOCHASTIC LIFE CYCLE SHIP DESIGN OPTIMIZATION

In the presented research study, a parametric model of a bulk carrier design is utilized in order to explore the technical and economic ship design features (design attributes) in the frame of a stochastic optimization procedure. The life cycle assessment of a newbuilding's investment that includes ship's acquisition and operation cost for ship's life cycle is affected by a variety of cost and other parameters have an inherent uncertainty. The ship design attributes are herein represented by six main ship parameters that define the basic characteristics of a vessel: length, breadth, depth, draft, block coefficient and speed. Among the ship characteristics that are related to high uncertainty are ship's energy consumption in terms of fuel consumption, fuel mix and fuel prices. In the present paper, an attempt is made to investigate how the uncertainty of estimations of the fuel consumption, fuel mix and prices, which are made at an early stage of ship design, can affect the outcome of the ship design optimization procedure with respect to ship's life cycle cost. Therefore, a stochastic optimization procedure is being applied, which is utilizing well established optimization algorithms and techniques in a robust and efficient manner. Sample results of this stochastic optimization are compared with solutions of a deterministic optimization and eventually lead to a rational basis for the decision making regarding the life cycle assessment of ship investments.