Offshore Support Vessel
Grontmij has developed a new basis supply concept that meets the general requirements in the offshore industry with construction and equipment that provides optimum performance. The Flex Supply concept meets the highest standards of safety and environmentally friendly shipping.
The vessel has a ‘clean design’ notation with double hull to all tanks containing fuel oil and other products harmful to the environment. The cargo section is arranged for various products meeting the demands of the offshore industry.
Twin Fin Propulsion System
Today diesel-electric propulsion systems in Offshore Service Vessels are most commonly equipped with rotatable azimuth thrusters driven by electric motors. This eliminates the need for rudder and stern tunnel thrusters, but makes the vessel more vulnerable due to the angle gears and other mechanical parts not being accessible from inside the vessel. Further, exploration in arctic areas calls for systems capable of withstanding ice forces and performing ice breaking duties. In case of break down on azimuth thrusters, it is normally necessary to go in dry dock for repair.
In order to overcome these obstacles, Grontmij, Berg Propulsion and Scandinavian Marine Group have developed a compact design for diesel-electric twin propeller vessels based on well-tested components through many years of experience, well-proven to work in harsh environments as well as in arctic areas.
The system is intended for Offshore Service Vessels working in Dynamic Positioning mode, but will also be a competitive alternative for other twin propeller vessels where noise and vibration requirements call for dieselelectric systems, such as seismic or cruise vessels.
The system is primarily intended for new buildings and for uncomplicated retrofits on existing azimuth-fitted vessels. Thanks to the system prefabrication, the work
and downtime at shipyard can be minimized.
The system has been designed and analyzed on Grontmij’s latest Flex90 – Arctic design which is a high powered Offshore Service Vessel. Obtained results from CFD simulations of the vessel with twin fin propulsion system show significantly higher total propulsive efficiency compared to the same vessel design with azimuth thrusters.