Siemens, Schottel Team For Podded Drive Product
Schottel-Werft and Siemens AG Marine Engineering have developed a new propulsion systems with a power range between five and 30 MW per unit.
The system is designed to provide efficient propulsion, adding improved maneuverability and safety to modern ships. The Siemens Schottel Propulsor (SSP) was designed to be suited for use aboard cruise vessels, large ferries and passenger vessels, cargo vessels, icegoing vessels, large offshore structures and navy vessels.
To improve efficiency, Schottel has developed the Twin Propeller. The propeller load is distributed to two propellers, one forward and one aft of the lower housing. With two airplane type fins added to the lower housing and 50 percent load per propeller only, the STP can achieve up to 20 percent efficiencies compared to alternative systems, the manufacturer said.
As a reference vessel for tank tests, the Meyer Werft-built 70,000- gt cruise vessel Century was chosen The ship has a propulsive power of 2 x 14 MW and a design speed of 22 knots.
Propulsion analysis were carried out in tank tests under the research and assistance of tank test institute SVA Potsdam, and with SSPA of Sweden.
The conventional diesel mechanic propulsion system of this vessel includes two shaft lines with 5.8 m propellers, and powered by 14 MW per shaft at 120 rpm.
Two standard podded drives with propeller diameters of 5.2 m and propeller speeds of 160 rpm, as well as two SSPs with propeller diameters of 5.4 m and propeller speeds of 150 rpm were analyzed by SVA Potsdam, by tank tests and cavitation tank results.
The results reportedly showed that the SSP would reduce the power consumption of a propulsion plant by 10 percent, so that either a higher speed of .5 knots (at the same consumption) or a lower fuel consumption of 10 percent could be achieved