For many years ships have been operating at only two loading conditions, design condition and ballast condition. Developments in the work economy have changed operational profiles of ships both from a speed point of view as well as larger variations in loading conditions. This makes the traditional practice of designing a ship for maximum speed and loading outdated. Ship designs should be optimised for the operational conditions the ship is expected to encounter.
A ship design should be optimised for the complete matrix of loading, speed and environmental conditions the ship encounters frequently. A number of steps such as understanding the operational conditions, defining a method for contract evaluation and validation of tools for “off-design” conditions have to be made before this approach will become common practice.
As a first step the Design For Sea JIP will focus on understanding the operational conditions of ships with special attention for the environmental conditions a ship encounters. Common day practice account for the environmental conditions using a Sea Margin of 15%. DeFoS will study operational Sea Margins and develop a method to more accurately determine the Sea Margin based on operational area and ship main particulars.
- Quantify the operational Sea Margin for a number of ship types;
- Simulate ship voyages to determine environmental load and required Sea Margin;
- Develop formulation to calculate Sea Margin in early ship design stage;
- Develop a method to validate EEDI and fw during sea trials;
- Demonstrate EEDI and fw validation.