Engine room arrangement for a marine vessel

Abstract

An engine room arrangement for a marine vessel comprises a fin formed at a rear portion of a hull of the vessel. The fin projects downward from the hull and protects a propeller of the vessel. A gear box is arranged at least in part in the fin and transmits a rotation of a propulsion shaft coupled to a main engine to a propeller shaft drivably coupled to the propeller. The fin provides extra buoyancy for the vessel. The propeller shaft is formed as a relatively short shaft, while the propulsion shaft is formed as a high speed/low torque shaft having a smaller diameter.

1 . An engine room arrangement for a marine vessel, comprising:
 a fin formed on a rear portion of a hull of the vessel, the fin projecting downward from the hull;   a gear box arranged at least in part inside the fin;   a propulsion shaft drivably coupled to the gear box, the propulsion shaft extending from the gear box to a front of the vessel and inside the vessel and being configured to be connected to a main engine or main motor of the vessel; and   a propeller shaft drivably coupled to the gear box, the propeller shaft extending rearward from the gear box to a propeller of the vessel.   
     
     
         2 . The engine room arrangement of  claim 1 , wherein the fin is open to an inside of the hull. 
     
     
         3 . The engine room arrangement of  claim 1 , wherein the gear box comprises a first portion connected to the propeller shaft, the first portion being arranged inside the fin, and a second portion connected to the propulsion shaft, the second portion being arranged at least in part inside the hull. 
     
     
         4 . The engine room arrangement of  claim 1 , further comprising an electric motor drivably coupled to the gear box to provide auxiliary power to the propeller and, optionally, to take out power for one or more electrical loads. 
     
     
         5 . The engine room arrangement of  claim 4 , wherein the electric motor is arranged at least in part inside the fin. 
     
     
         6 . The engine room arrangement of  claim 1 , wherein the propeller is a controllable pitch propeller, a plurality of hydraulic passages being formed in the propeller shaft for supplying hydraulic fluid to control a pitch of the propeller. 
     
     
         7 . The engine room arrangement of  claim 1 , wherein the propulsion shaft has a diameter that is smaller than a diameter of the propeller shaft ( 22 ). 
     
     
         8 . The engine room arrangement of  claim 1 , wherein the propulsion shaft is a high speed/low torque shaft configured to rotate at between around 500 rpm and around 2200 rpm and has a length of between around 0 m and around 50 m and a diameter of between around 100 mm and around 300 mm. 
     
     
         9 . The engine room arrangement of  claim 1 , wherein the propeller shaft has a length of less than 10 m, for example, between around 2 m and around 10 m. 
     
     
         10 . The engine room arrangement of  claim 1 , wherein the propeller has a diameter of more than 2 m, for example, between around 2 m and around 10 m. 
     
     
         11 . The engine room arrangement of  claim 1 , wherein the fin and the hull are integrally formed. 
     
     
         12 . The engine room arrangement of  claim 1 , comprising:
 a plurality of fins having the same configuration and being spaced apart in a transverse direction of the vessel, a gear box being arranged at least in part in each fin and being drivably connected to corresponding ones of a plurality of propulsion shafts and a plurality of propeller shafts.   
     
     
         13 . A marine vessel, comprising:
 a main engine or main motor; and   an engine room arrangement for a marine vessel including:
 a fin formed on a rear portion of a hull of the vessel, the fin projecting downward from the hull; 
 a gear box arranged at least in part inside the fin; 
 a propulsion shaft drivably coupled to the gear box, the propulsion shaft extending from the gear box to a front of the vessel and inside the vessel and being configured to be connected to the main engine or main motor of the vessel; and 
 a propeller shaft drivably coupled to the gear box, the propeller shaft extending rearward from the gear box to a propeller of the vessel. 
   
     
     
         14 . The marine vessel of  claim 13 , wherein the engine room arrangement includes a pair of fins spaced apart in the lateral direction of the vessel, each fin having a gear box arranged at least in part inside the fin, each gear box being connected to a corresponding one of a pair of main engines via a corresponding propulsion shaft. 
     
     
         15 . The marine vessel of  claim 13 , wherein the marine vessel is an arctic vessel, for example, an arctic supply vessel or an anchor handling tug supply vessel.