Trimaran Concept for Offshore Operations in Northern Seas

A trimaran concept for offshore operations has been developed. Vessel features include low response in waves, low resistance for efficient transfer over long distances, launching positions for intervention equipment and a large deck area. The vessel may, in different versions, represent an interesting design to be used for field development and for inspection, maintenance and repair in Northern Seas. Efficiency in operation has been focused on in the development of this concept. To build a vessel for the future one has to study where the industry is moving and where likely work will be coming up in the time to come. Advances in technology, both in ship design and in subsea intervention are hard to predict and the capacities and characteristics for the future are hard to foresee. Some characteristics are, however, likely to be desired in the future as well. These are characteristics such as low vessel motions, good fuel economy, a large deck area and high loading capacity, to name a few. These characteristics are, in turn, perhaps not easy to combine. One vessel concept that combines some of these features in an elegant way is the trimaran. Concept development and theoretical analysis were followed up with tank testing. A 1:50 scale model was built by Technical Services and tested in the 60 m towtank at Memorial University of Newfoundland. Resistance and Motion tests were performed and compared with computer analysis. Comparison of results show good consistency between analysis and tank tests.