Van der Velden reveals efficiency innovations

The company is working with German propeller manufacturer Mecklenburger Metallguss (MMG) to build a 97m2 Energy Saving Package (ESPAC) system for three 18

,

000 teu vessels under construction for CMA CGM at Shanghai Waigaoqiao Shipyard in China. The package combines a fixed-pitch propeller with an asymmetric leading edge rudder featuring a propulsion bulb

and

adapted hubcaps.

“These are the largest rudders we have ever built

and

,

by putting them together with 10-metre MMG propellers

,

the whole package will minimise fuel consumption

,

cavitation

,

vibration

and

maintenance

,

” said Edwin van Buren

,

director R&D at Van der Velden.

Another new system provides direct feedback to helmsmen about forces acting on their rudders. The Barke Optimised Steering System (BOSS) displays force measures on an LCD panel on the bridge

,

and

can transfer the data to the ship’s navigational system.

“It is important to know how much stress is placed on the rudder

,

” said van Buren. “The greater the resistance

,

the more fuel is consumed. Fewer steering corrections reduces overshoots

and

shortens the distance travelled. This quickly delivers significant fuel savings.”

The company can install measurement sensors on rudder stocks with a view to installing the whole system at a later date. “This pre-installation avoids costly dry-docking in the future

,

” noted van Buren.

BOSS has been installed on CMA CGM’s ultra large container vessels

Ural

and

Volga

,

and

Van der Velden has carried out commissioning

and

sea trials in partnership with Damen’s R&D team. During IMO manoeuvring

and

endurance tests

,

Van de Velden recorded BOSS data

and

synchronised with the vessel’s dynamics.

A third system is designed primarily for coastal

and

inl

and

ships. The retractable FLEX tunnel system is said to improve manoeuvrability

,

speed

and

fuel efficiency by around 10%. It was developed in collaboration with the German Development Centre for Ship Technology

and

Transport Systems

,

and

combined with an optimised hull design is said to ensure optimal water flow at all depths

and

load conditions.

“We developed a retractable tunnel because for about 85% of the time

,

loaded

inl

and

barges sail in deeper water

,

” explained van Buren. “In these situations

,

tunnels are unnecessary. In fact

,

they only decrease propulsion capacity

and

increase fuel consumption.”