Ship equipped with main propeller and additional propeller and hybrid operating method therefor

Abstract

[Problems] To reduce the fuel consumption without impairing operational safety of the ship [Solution to Problem] A ship 10 configured to obtain propelling force by driving a main propeller 11 with a main engine 12 is provided with an additional propeller 20 and a driving unit therefore. The additional propeller 20 is disposed at a ship bottom or at a rising section of the ship bottom, in a position different from the main propeller 11. Further, the output of the driving unit of the additional propeller 20 is 25% or less than the output of the driving unit of the main engine, and the operating condition can be selectable between regular operating condition in which propelling force is obtained by driving the main propeller 11 and die other operating condition in that propelling force is obtained by driving the additional propeller 20.

1 . A ship configured to obtain propelling force by driving a main propeller with a main engine, and provided with an additional propeller and a driving unit for the additional propeller,
 wherein one or a plurality of the additional propellers is disposed at a ship bottom or at a rising section of the ship bottom, in a position different from where the main propeller is disposed, and   operating condition is selectable between regular operating condition in which propelling force is obtained by driving the main propeller and the other operating condition in which propelling force is obtained by driving the additional propeller.   
     
     
         2 . The ship according to  claim 1 , wherein the additional propeller is a duct propeller. 
     
     
         3 . The ship according to  claim 2 , wherein an operational position of the duct propeller is selectable between a state of being assembled at the outside of the ship and the other state of being retracted to the inside of the ship. 
     
     
         4 . The ship according to  claim 2 , wherein the duct propeller is provided at a stern area. 
     
     
         5 . The ship according to  claim 2 , wherein the duct propeller is provided at a bow area. 
     
     
         6 . The ship according  claim 2 , wherein the duct propeller is provided at an intermediate area in the ship length direction. 
     
     
         7 . The ship according to  claim 2 , wherein the duct propeller is rotatable around a vertical shaft line. 
     
     
         8 . A method far operating a ship configured to obtain propelling force by driving a main propeller with a main engine, and provided with an additional propeller and a driving unit for the additional propeller,
 wherein the additional propeller is disposed at a ship bottom or at a rising section of the ship bottom, in a position different from where the main propeller is disposed, and   the ship is propelled by driving the main propeller in a load condition, and the ship is propelled by driving the additional propeller in an unload condition.   
     
     
         9 . The method for operating a ship according to  claim 8 , wherein the additional propeller is a duct propeller, and the duct propeller is provided at a bow area, and the ship is propelled in a stern direction by driving the duct propeller in an unload condition. 
     
     
         10 . The method for operating a ship according  claim 9 , wherein the duct propeller is retractable to the inside of the ship, and the ship is propelled in the stern direction by driving the duct propeller after extracting the duct propeller from the inside to the outside of the ship so as to be assembled therein an unload condition. 
     
     
         11 . The method for operating a ship according to  claim 9 , wherein the main propeller is partially or entirely disposed on a draft line when the duct propeller is driven in the unload condition. 
     
     
         12 . The method for operation a ship according to  claim 8 , wherein an air blowing section is provided on an upper portion of a duct of the additional propeller to blow out air from the air blowing section, and the ship navigates generating a flow of bubbles at the ship bottom.