ESD DESIGN FOR OFFSHORE VESSEL
CUSTOMER: SHIP DESIGN OFFICE
RELATED SERVICES: CFD, RUDDERS, DESIGN
SCOPE OF WORK:
The aim of this project was to design an Energy Saving Device (ESD) for an offshore vessel. The only allowed modification was the rudder shape, therefore several downstream ESD’s were studied with no modification of propeller hub cap.
Three options were considered:
- Twisted rudder with rudder bulb,
- Standard rudder with rudder bulb and fins,
- Twisted rudder with rudder bulb and fins.
The design of the different solutions was carried out by means of self-propulsion CFD simulations, also using a parametric CAD model allowing fast geometry modification during the optimization process.
It has been highlighted that the best option would be ESDs full combination: twisted rudder with rudder bulb and fins, reaching a 3.5% of improvement.
The other configurations, standard rudder with bulb and fins and twisted rudder with bulb, have allowed a gain of 3.2% and 2.4%, respectively.
These results have been verified by towing tank tests ordered by the customer.