In Nodosa Shipyard, the design, construction and repair of fishing vessels is one of his potential markets, both for high seas and coast ships. Nodosa Shipyard has built different kinds of fishing vessels, including tuna vessels, longliner, trawler…
For the longliner newbuilding 282, Nodosa has selected Vicusdt for different hydrodynamic analysis, the supply of propeller and rudder design.
Vicusdt carried out a study of the preliminary hull of this newbuilding, using CFD tools, for two loading conditions and for three speeds. This analysis included a preliminary powering prediction in order to check if the selected engine would be sufficient for the target speed and this hull forms.
Due the results of this preliminary study, an optimization of the hull was carried out, in order to decrease the resistance and brake power for the same speed. With a modification in the bulbous bow, an important resistance reduction was obtained, and a change for the main engine or maximum speed was no needed.
To improve the wake field, another modification was carried out in the aft bulb. This new hull has a more uniform wake comparing with the original one leading to a better propeller-hull interaction.
Another small modifications, like appendages alignments were also suggested to the yard taking into account the stream lines.
This longliner will be equipped with a 5 blades and 2.7 m wake adapted VICUS fixed pitch propeller. This propeller was designed by means of “in behind” selfpropulsion analysis, taking into account the flow and water speed in the propeller area as well as the interaction with the hull. This wake adapted propeller ensures a high efficiency and low noise and vibration levels and the compliance for requirements and specifications for speed.
The rudder design was done applying optimization techniques coupled with potential and viscous CFD codes, helping to define the optimum profile geometry in each section. In this case, the longliner will be equipped with a twisted rudder with bulb
28 enero 2016
