ICE MANAGEMENT FOR STEERING OF LARGE ICE FLOES

摘要

A study has been carried out to assess the feasibility of using ice management to influence the drift trajectories of potentially hazardous ice floes. A large ice floe drifts under the action of wind and water drag, Coriolis force, and the forces exerted by the surrounding ice cover. For a massive ice floe, the force required to divert the drift trajectory away from an offshore installation would be far beyond the capabilities of available vessels. However, such trajectories may be influenced by selectively breaking the ice in the vicinity of the floe. The present investigation employs a numerical model to simulate the drift of large floes embedded in an ice cover. The model is based on solving a set of equations that describe the conservation of mass and momentum, and constitutive equations of the ice cover. The large floes are considered to move as rigid bodies. The study consists of validation tests and evaluation of the effectiveness of several ice breaking scenarios. A validation test considers the drift of large ice floes from the Chukchi Sea. Predictions of floe drift and deformation modes of the ice cover are compared to observations obtained from available imagery. The investigation next examines the effectiveness of scenarios of ice breaking. Selected options of ice breaking around a large floe are introduced by altering ice cover concentration. The results indicate that ice management can alter the trajectories of large hazardous floes.