쇄빙상선의 빙하중 고찰 및 빙해역 항행 모델

Abstract

As the oil price soars and the Russian economy revives, increasing new orders of icebreaking cargo vessels become an important issue in the world's shipbuilding market. One of the areas of the concern which arises during navigation in ice-covered waters is the magnitude of ice impact loads encountered by ships. However, the accurate estimation of ice load still remains as a rather difficult task in the design of icebreaking vessels.

This study focuses on the development of a simple ice load prediction formula for the ice-going cargo vessels. For this purpose, various ice load scenarios are discussed concerning possible ship/ice interaction modes. Since the maximum ice loads are expected from unbroken ice sheet, these load are most likely to be concentrated at the bow area.

In this study, published ice load data for icebreaking vessels, from the model tests and also from full-scale sea trials, are collected and then several ice load prediction formulas are compared with these data. Finally, based on collected data, a new, semi-empirical, ice load prediction formula is recommended for the design of icebreaking cargo vessels. An ice load estimation software "IceView" is developed by using ice load prediction formulas.

In addition, an ice transit model for icebreaking cargo vessels in the Northern Sea Route is studied. The ice transit model can select optimum sea routes with the shortest navigation time and the lowest operation cost. This model, with basic information such as ship capabilities, transit directions and months of transit, can calculate total transit distance and elapsed time, mean speed, operation cost for each vessel. In the ice transit model, environment information such as the site-specific ice conditions, wave and wind states is utilized for four different months (April, June, August, and October) along the Northern Sea Route. The model also defines the necessary periods of an icebreaker escort. Then the optimum sea routes are selected and visually displayed on the digital map using a commercial software ArcGIS. Usefulness of the selected sea routes is discussed.