Energy-saving Technology

Technologies enabling fuel saving by improving the propulsive efficiency

Kawasaki RBS-F

Kawasaki RBS-F
Kawasaki RBS-F (Rudder Bulb System with Fins)

"Kawasaki RBS-F" (patented) is an energy saving device installed on a rudder. It consists of a streamline-shaped rudder bulb and airfoil-shaped fins.

The rudder bulb brings smooth inflows to the propeller, and the fins produce thrusts in the rotational flows generated by the propeller. As a result, Kawasaki RBS-F reduces the required propulsive power by 2% to 7%.
Kawasaki RBS-F has been installed on more than 100 ships including LNG Carriers, LPG carriers and bulk carriers.

Kawasaki SDS-F (Semi-Duct System with contra Fins)

Kawasaki SDS-F (Semi-Duct System with contra Fins)
"Kawasaki SDS-F" (patented), which is fitted in front of the propeller, is an energy saving device. It consists of contra fins and a semi-duct.

The contra fins produce reverse rotational inflows in the propeller rotating direction and reduce the rotational flows behind the propeller, resulting in the improvement of the propulsive efficiency. The semi-duct produces thrusts in the oblique downward flows of bilge vortices and also prevents the flow separation at the stern position.

Kawasaki SDS-F achieves 3% to 7% energy saving, and by fitting it along with our another energy saving device, Kawasaki RBS-F, further energy saving can be expected.

Kawasaki SDS-F has already been installed on five oil tankers.


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