Technology development

Energy saving devices

Energy saving duct

Super Stream Duct® (SSD®) and Semi-Circular Duct reduce the fuel consumption by about 3~8%. They recover the energy loss due to longitudinal vortices generated at the stern of full ships such as VLCC or Bulk Carrier and generate thrusting forces. More energy saving is possible by using these ducts together with SURF-BULB® which is installed behind a propeller.


SURF-BULB® (Swept-back Up-thrusting Rudder Fin with BULB) reduces the fuel consumption by about 3~5% by converting the rotational energy behind a propeller to the thrusting force.
For full ships such as VLCC or Bulk Carrier, more energy saving is possible by using SURF-BULB® together with the energy saving duct (SSD®) which is installed in front of a propeller.


Contra-Rotating Propeller

Contra-Rotating Propeller (CRP) consists of two propellers which are aligned in front and behind and rotates in opposite direction each other. The propulsive efficiency is improved by the behind propeller by recovering the energy loss due to rotational flow behind the fore propeller. Now, CRP is adopted for VLCC, Bulk Carrier and domestic ships with electrical propulsion system and contributes to the improvement of fuel consumption and reduction of CO2, Nox and Sox emission.

Rudder Bulb

Behind a Contra-Rotating propeller, because there is no rotational flow to be converted to the thrusting force by fins, the rudder bulb which is the finless SURF-BULB® is adopted for CRP.

CRP +Semi-Circular Duct +Rudder Bulb



L.V.Fin (Low Viscous resistance Fin) is a pair of triangle stern fins installed in front of a propeller on both of starboard and port side. L.V.Fin straightens the complex stern flow including bilge vortices and reduces the hull resistance. About 2~3% energy saving is confirmed in speed trial of full ships. Because of simple form and easy installation, L.V.Fin has been adopted to many ships.

Low Wind resistance Accommodation

Square corner cut accommodation reduces wind resistance of ship by about 10~15%. This technology is put to practical use for reducing sea-margin together with Ax-Bow® or LEADGE Bow®.

Low Wind resistance Accommodation (Right side)