Ice accretion increases a ship’s weight and alters its stability characteristics. This module provides accurate calculations of the added weight and COG due to ice accumulation.

Layout

The Ice Accretion module in LOCOPIAS calculates the weight and center of gravity (COG) of ice accretion, which can affect a ship’s stability and must therefore be taken into account. When navigating through polar waters, additional hazards such as the increase of weight by accumulation of ice can lead to a decrease in stability. The software uses the ship’s outer layout to determine the ice accretion on all vertical and horizontal surfaces.

The ice accretion can then be found in the weight list and is included in further calculations, such as the ship's position, intact stability and longitudinal strength. The module is available for all ship types, but primarily applicable to those sailing without deck cargo. Ice accretion on deck cargo cannot be specified with this module.

The main screen of the Icing module.

Upon entering the module's main screen, the ship’s outer layout is displayed. The user can select ice fields in the left window, which provides an overview of all ice fields. The selected ice field is highlighted in the graphical display. In the ship's graphical display (right window), the user can rotate the ship (left mouse button), zoom in (scroll wheel), and pan (middle mouse button).

Select surfaces:
Select the vertical and horizontal surfaces on which ice may accumulate. Multiple surfaces can be selected for simultaneous application.
Apply ice layer:
Specify the thickness of the ice layer for the selected surfaces by filling the values in the corresponding fields (in centimeters [cm]). If an ice thickness is specified for an ice field, this thickness is displayed in the graphical presentation. For ice fields intersected by the ship's waterline, only the ice above the waterline is included. The software will then calculate the resulting ice weight and its center of gravity (COG).
Review calculations:
The computed ice accretion appears in the weight list, and is automatically included in the further calculation of position, stability and/or strength.

The weight list screen, showing the ice weight items for the example condition used.