To better model ships in ice, ABS is developing a simulation technology called “event mechanics”, together with researchers at Memorial University of Newfoundland (MUN).
By using event mechanics, designers and class can evaluate how different designs for ships and offshore structures will behave in different ice conditions.
Event mechanics means modelling complex problems as a series of discrete events. One thing happens then another thing happens.
Problems in real life can often happen as a series of events – some corrosion in one area leads to weakening in another which leads to wear somewhere or components corroding in a complex way.
The previous approach is continuum mechanics, where researchers examine the behaviour of materials as a single mass.
The simulation process is called “General Event Mechanics (GEM) simulation”, a numerical technology, based on mathematical models of the physical system.
By running GEM to calculate how different components will behave it is possible to determine how different forces and conditions will affect them.
It can be used for evaluating both the risks of standard ocean-going ships in low impact icy conditions, and low ice class ships.
It can also be used to analyse how well floating structures can stay in their position, when subjected to different ice concentrations.
Predictions
In the realm of ship operations, it might be possible to integrate the mechanical modelling with analysing imagery, radar and 3D laser scanning, to make better predictions of what will happen.
For example it could be used as part of a collision avoidance system, or route optimisation guidance, together with data with predictions of future ice conditions.
It’s also possible that the industry can begin to apply artificial intelligence and machine learning to compare ice conditions and temperature profiles with data from previous years and make projections by region.
The work already achieved on safe speed in ice could be the foundation for the greater use of sensors to monitor operations and understand better the conditions in which ships can safely operate.
Longer term
In the longer term, this could lead to the further optimisation of ship structures that make them more efficient for ice operations once the limits are better understood.
These factors create the opportunity for progressive organizations to combine data and insights to drive efficiencies.
The intention would be to provide a level of safety acceptable under the Polar Code that could enable shipowners to undertake voyages with a high confidence factor based on data.
In particular, these changes will facilitate growing tanker trade opportunities in at least two areas. Reduced sea ice especially along the Northern Sea Route is already creating east bound transit opportunities for tankers and gas carriers from the Yamal region.
Despite its controversial profile to some, development of North American Arctic oil and gas in the future is likely. Work on establishing enhanced safety criteria now will make it possible sooner.
It is becoming clear that as overall sea ice extents are reducing, the mobility of multi-year ice is increasing. As a result, going forward, PC6 and PC7 ice class ships should become the workhorses for polar shipping, displacing IA Super and 1A ships from the marketplace.
The PC6 and PC7 ships are intended for first year ice operations but unlike their Baltic rule cousins, the Polar Class rules implicitly account for the likelihood of encountering multi-year ice inclusions.
Balancing climate concerns
Propulsion power, along with hull form, are the key characteristics that enable transit in ice.
But the intention of the IMO Energy Efficiency Design Index (EEDI) is a trend to reduce installed power for all ships. Lower ice class vessels and non-ice strengthened ships are subject to EEDI.
We need to reconcile the opposing needs of more installed power to get through ice, and less power to improve or be EEDI compliant on conventional ice class ships.
Icebreakers are typically higher ice classes (PC1 thru PC5) and as such are exempt from the EEDI.
These specialized ships provide assistance to keep other ships moving. They have a specific role in support of shipping operations in areas including the Baltic Sea, along the Northern Sea Route and in the Gulf of St Lawrence.
Harsh Environment Center
To facilitate the continued development of the tools needed to improve safety of ice operations, ABS established a “Harsh Environment Technology Center (HETC)” on the campus of Memorial University in St. John’s, Newfoundland and Labrador in 2009.
The primary objective of the HETC is to develop technology for the design and assessment of ships and offshore structures that operate in harsh environments particularly the Polar regions and low temperature areas.
Newfoundland was considered a prime location to establish an Arctic research center due to its excellent educational program, offshore oil exploration and development activities in the region, and progressive approaches in supporting research activities.