Aft shape effects of modern heavy-tonnage ships on ice performance when moving astern

Abstract

Object and purpose of research. Object of the study is the analysis of aft shape effect of modern heavy-tonnage ships on ice performance indices when moving astern. The purpose of the work is to identify additional specific factors that affect the performance of ice performance when moving stern first, which are usually not taken into account when considering moving ahead. Materials and methods. Material for the development are provided by the data from model experiments results, as well as previously published works devoted to the study of the ship's stern-first movement in ice. Main results. Models tests results of large capacity ice-going ships models moving stern first in an ice basin are analyzed. The phenomena of stern interaction with the ice cover in comparison with the mode of bow first movement are identified and discussed. Approximate estimates are done of the size of ice fragments formed when large capacity ships are moving astern. The obtained results create prerequisites for the development of a methodology for designing large capacity ships with increased ice-going capability. Conclusion. Analysis of heavy-tonnage vessel interaction with ice when sailing astern was carried out based on model tests in the ice basin. It was concluded that in order to develop the calculation procedure for ice resistance when the ship is sailing astern, it is necessary to elaborate new criteria for describing the main components of the ship hull lines and peculiarities of hull interaction with ice.