Author(s): Bin Mei; Wanling Zhao; Weifeng Li
Linked Author(s):
Keywords: Convoy navigation; Following strategy; Ice concentration; Navigation resistance
Abstract: Ice-covered waters in polar and high-latitude regions are complex and variable, and the icebreaker-escorted ships need an effective approach to make navigation decision. The core components of the following strategy are following distance and speed. Nowadays strategies rely on manual and empirical settings and fail to account for the dynamic closure of broken-ice channels. To address this issue, this study proposes a quantitative method for computing following strategies in ice convoy operations. A broken-ice channel contraction model is developed, incorporates scaling factors and boundary-mixing corrections to predict the evolution of ice concentration for ships of different sizes. The empirical ice-resistance model and hydrodynamic resistance calculations has dedicated to the total resistance of following ships at various speeds and distances. The propulsion constraints are then imposed to obtain the maximum feasible following speed, while a deceleration dynamics equation is established to calculate the minimum stopping distance. Combining the speed and distance constraints for multiple following ships yields a fleet-wide feasible domain for following strategies. Case studies demonstrate that the proposed method can capture resistance and propulsion limitations induced by channel closure, enhances convoy navigation safety and continuity.
Year: 2026