RELATED SERVICES: CFD SIMULATION, DESIGN, HULL FORM OPTIMIZATION, SHIP RESISTANCE & POWERING PREDICTION
SCOPE OF WORK:
- 3D hull model generation
- Ship resistance calculation
- Propellers preliminary sizing based on CFD calculations
- Sensibility analysis for the longitudinal centre of gravity.
- Propeller tunnel design and resistance analysis.
- Self propulsion calculations.
Within RODMAN’s 90 ft catamaran Project, intended for the shipowner TRASMAPI, VICUSdt has accomplished the optimizations of the hull, improving significantly her performance.
First, skegs of the demi-hulls were modified in order to get two objectives: on one hand, resistance reduction, and on the other, improve water flow towards the propeller.
Also, a preliminary sizing of the propellers was developed based on the former power prediction, with the purpose of determining the dimensions of the stern tunnels for those propellers. In addition, design considerations for the tunnels were provided to get a proper performance of the propulsion.
After this process, a final power prediction was calculated, taken into account the influence of every additional modification that raised during the design stage: changes in longitudinal position of the centre of gravity and displacement, whose variations are susceptible to cause significant modifications on ship’s resistance and trim on fast boats. Simulation of the propellers performance in self-propulsion condition let efficiency and propeller cavitation response to be verified.
During sea trials, carried out in Vigo bay, the success of this optimization action was ascertained, as required speed was correctly achieved.