Propulsive performance in a seaway

by Phd. Soizic Annick Gabrielle Joncquez, project manager at FORCE Technology
 

 

The present proposal prepares the steps for a major change in ship design! 

Objective

Ships have traditionally been designed to a trial or design condition in calm water, and not to the actual weather conditions en route. The strong focus on fuel savings and associated reduction of emissions from ships calls for a new holistic approach to ship design. The objective of the present project is to develop a method by which different ship designs can be assessed in – not only calm water – but in a realistic seaway. The best design option is the one with the best overall propulsive performance in a seaway, the added resistance from waves being included.

This objective is achieved in two steps.

i) The first step consists in evaluating the added resistance in head seas and in oblique seas. The added resistance in waves may be determined by means of seakeeping tests with scale models. This method is typical rather expensive and time consuming taking into account cost for model building and tests in waves. But with AEGIR, a 3D-panel time domain code, Soizic has proven and demonstrated that it is possible with a reasonable accuracy to calculate the added resistance of a ship in head seas. In this project, AEGIR will also be used to calculate the added resistance in oblique seas.

ii) The second step consists in integrating the added resistance with a route simulation program or by combining with a typical wave scatter diagram in order to evaluate the ship propulsive performance in a seaway. The SeaTrend propulsive model, developed in the DCMT funded project on performance monitoring of ships will be used.

Project activities

1. Planning 
2. Effect of alternative bow shape in head seas 
3. Calculations of added resistance in oblique seas with AEGIR 
4. Calculation of propulsive performance in a seaway for a vessel, incl. alternative foreship 
5. Documentation and sharing of results

The project will be closely linked to the following DCMT projects, which will form the basis:

• Second-order forces and moments acting on ships in waves
  by Soizic Annick Gabrielle Joncquez, Ph.D., Project Manager, FORCE Technology
   
• Application of RANSE CFD for Ship Hydrodynamics
  by M.Sc. (Naval Architecture), Phd. Claus D. Simonsen, Senior Specialist, FORCE Technology
  

 

For further information on this project, please contact Soizic Annick Gabrielle Joncquez (scj@force.dk), project manager, FORCE Technology.