Abstract
Popov et al. (1967) proposed an approach to evaluate the ice loads during ship-ice impact. The approach firstly calculates the reduced mass and velocity of ship-ice system based on the principle of conservation of momentum. Secondly, it predicts the ice loads by assuming that the reduced kinetic energy is absorbed by the work of contact crushing stress. The added mass used at the first stage of Popov approach is estimated with simplified empirical formulas.
This paper attempts to introduce an improved method for the prediction of ice loads by accounting for the influence of the added mass, calculated by potential flow theory, in Popov’s approach. The evaluation of ice loads involves the effects of: 1) ship and ice geometry; 2) waves; and 3) hydrodynamic cross coupling between ship and ice.
A potential flow theory model, consisting of a ship and an ice floe, is built to calculate the added mass, wherein the ship is approaching the free-floating ice at a constant speed in random waves. The added mass is subsequently integrated into the Popov approach to evaluate the ice loads. Comparisons of results with those from the conventional Popov prediction reveal that the ice loads are considerably affected by the influence of added mass in waves. Notwithstanding this, ice loads may not be sensitive to hydrodynamic interactions.
