The capability to continually perform operations in ice is a function of multiple design factors. These factors may directly influence one another and are integral to the design spiral. The compromises made in vessel design directly impact the vessel’s noise and vibration characteristics. Unlike conventional ships, icebreakers are subject to additional dynamic loads arising from interaction with ice. Because icebreaker hull forms are generally influenced by unique performance requirements, engineering past experiences, production feasibility, and risk mitigation during operation, early design development to optimize both ship arrangement and machinery system parameters is necessary to avoid vibration problems. Numerical modeling techniques like the finite element method are indispensable when evaluating the low frequency vibration of a vessel during the design stage. Methodologies for estimating the dynamic loads associated with common shipboard excitations such as unsteady propeller forces, cavitation pressure pulses and propulsion machinery are non-trivial, but established. Estimating the spatial and temporal characteristics of dynamic loads associated with ice operations, such as icebreaking and ice milling, is a challenge. In this paper, techniques for estimating dynamic loads associated with icebreaking and ice milling operations are discussed. Approaches to applying these forces to a finite element model for the evaluation of these forces on a vessel’s low frequency vibration are presented.

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