On the Optimization of Ship Motion in Heavy Ice Conditions

Abstract

For a given ship, its speed in ice decreases as ice conditions become more severe until it can no longer move continuously. The transition speed concept provides a valid cut-off point below which a ship has to switch to the discontinuous or ramming mode of operation. Solutions for the continuous and ramming mode ship motions and an analysis of a typical ramming cycle are presented. A general solution valid for all stages of ramming is given. It provides a closed form equation which can be used both to study the influence of ship characteristics and operational tactics upon ship performance and to optimize ship motion in heavy ice conditions decreasing fuel consumption and transit time.