The development of route decision-making method based on tailor-made forecast 2d wave spectra due to the operation profile of the vessel

Abstract

This paper developed the new route decision-making method that implements the wave-added-resistance estimation method using forecast 2d wave spectra in a frequency and a direction domain specified through a ship's voyage route. In the accepted conventional method, a 1d idealized spectrum is applied to estimate the wave-added resistance calculation in the process of performance evaluation in the route decision-making algorithm. Wave-added resistance estimation using an 1d idealized spectrum assumes that the statistical characteristics of the sea do not vary over the ship's route with regard to geography and season. In the real world, the characteristics of the sea continually vary according to the voyage route in which a vessel passes by. This paper provides the method that calculates the added resistance of waves using forecast 2d wave spectra, that provided tailor-made stochastic data at any particular time and position along the route of the vessel.The difference of the wave-added resistance estimation using conventional 1d idealized spectrum method and the proposed forecast 2d wave spectra method is investigated by the comparative study of the estimation results, model tests, and the measured power during the real voyage case of 173K LNGC in the Pacific and Atlantic ocean.