Damage Stability Evaluation for a Polar Navigation Vessel with Ice Accumulation

Objectives Aiming at the safety problems caused by icing and damage of ships under polar navigation conditions, the stability evaluation of iced ships under damaged conditions is carried out. Methods Firstly, based on the theory of droplet icing, an icing prediction model was established. Taking DTMB-5415 ship as the research object, the influence of wind speed and temperature on ship icing was analyzed. Secondly, the changes of the restoring arm curve and the center of gravity of the intact ship and the damaged ship under different icing time are calculated, and the influence of icing and damage on the static stability of the ship is analyzed. Finally, the ultimate dynamic inclination angle is used to evaluate the dynamic stability of the ship, and the ultimate dynamic inclination angle and ultimate wind speed of the damaged ship under different icing time are calculated. Results The research shows that the combined effect of icing and damage will significantly reduce the stability of the ship. After 6 hours of icing, the ultimate dynamic inclination angle of the damaged ship is reduced from 64.8 ° of the intact ship without icing to 62.1 °, and the ultimate wind speed is reduced from 33.1 m / s to 16.0 m / s. After 12 hours of icing, the stability of the damaged ship does not meet the requirements of IMO regulations. Conclusions The research can provide an important reference for the analysis of the influencing factors of ship icing and the evaluation of ship stability under the combined action of icing and damage.