Foreship arrangement for a vessel of the displacement type

Abstract

A foreship arrangement for a vessel of the displacement type, which foreship consists of the part of the ship in front of the vessel's midship mark ( 2 ) and which vessel has a transversely symmetrical hull form about its centre line (CL) and a substantially conventional bow form below its design water line (Tdwl), characterised in that the stem line ( 1 ) of the vessel turns substantially backwards in relation to the length direction of the ship from a transition point (B) at or immediately above the design water line (Tdwl).

1 . A foreship arrangement for a vessel of the displacement type, which foreship consists of the part of the ship in front of the vessel's midship mark ( 2 ) and which vessel has a transversely symmetrical hull shape about its centre line (CL) and a substantially conventional bow form below its design water line (Tdwl), characterised in that the stem line ( 1 ) of the vessel turns substantially backwards in relation to the ship length direction (negative x-direction) from a transition point (B) at or just above the design water line (Tdwl). 
     
     
         2 . The arrangement according to  claim 1 , characterised in that the stem line ( 1 ), starting from a lower point (A) at the vessel's base line ( 3 ) rises and has a substantially increasing curvature in the forward direction of the vessel to the transition point (B), and that the stem line ( 1 ) from the point (B) continues to rise, but with a substantially diminishing curvature and in the aftward direction of the vessel, optionally broken by one or more straight portions, to an upper point (C). 
     
     
         3 . The arrangement according to  claim 2 , characterised in that a spray board ( 5 ) extends out from the upper point (C), the stem line ( 1 ) being bent sharply forward at said point (C) and being terminated at the top of the spray board ( 5 ). 
     
     
         4 . The arrangement according to  claim 1 , characterised in that the vessel's flare angles in the foreship, and above the design water line (Tdwl) are in the range of 9-45 degrees relative to the height direction of the vessel. 
     
     
         5 . The arrangement according to  claim 1 , characterised in that the vessel's stem angles between the transition point (B) and the upper point (C) increase from 0 degrees at the transition point (B) to 55 degrees at the upper point (C) relative to the height direction of the vessel. 
     
     
         6 . The arrangement according to  claim 1 , characterised in that the entry angle of the bow at the design water line (Tdwl). and in a plane coincident with the horizontal plane (the xy plane) is in the range of 16-25 degrees relative to the centre line (CL). 
     
     
         7 . The arrangement according to  claim 1 , characterised in that the frame lines ( 10 ,  20 ,  30 ,  40 ,  50 ) of the foreship are designed transversely symmetrical about the centre line (CL), and starting respectively from first points (D 1 , D 2 , D 3 , D 4 , D 5 ) run almost perpendicularly from CL and increase in breadth (the y-direction) from the centre line (CL), whereafter the frame lines ( 10 ,  20 ,  30 ,  40 ,  50 ) respectively merge into the bilge (G 1 , G 2 , G 3 , G 4 , G 5 ) at a given bilge radius, from which bilge and up to second points (E 1 , E 2 , E 3 , E 4 , E 5 ) the frame lines ( 10 ,  20 ,  30 ,  40 ,  50 ) are outwardly sloping, and at which points (E 1 , E 2 , E 3 , E 4 , E 5 ) the outwardly sloping frame line form is terminated and then runs respectively upwards as a curved frame line form back to the centre line (CL) at third points (F 1 , F 2 , F 3 ) and continues upwards with very gentle curvature towards the centre line CL to third points (F 4 , F 5 ). 
     
     
         8 . The arrangement according to  claim 3 , characterised by the following ratios for a water line length (Lwl) in the range of 60-90 metres: Bwl/Tdwl=2, Lwl/Bwl=3, Lwl/Tdwl=5, Htdwl/Bwl=0.5 and Lwl/Htdwl=2. 
     
     
         9 . The arrangement according to  claim 3 , characterised by the following ratios for a water line length (Lwl) in the range of 90-120 metres: Bwl/Tdwl=3, Lwl/Bwl=4.5, Lwl/Tdwl=13, Htdwl/Bwl=0.8 and Lwl/Htdwl=5.5. 
     
     
         10 . The arrangement according to  claim 3 , characterised by the following ratios for a water line length (Lwl) in the range of 120-150 metres: Bwl/Tdwl=3.5, Lwl/Bwl=5, Lwl/Tdwl=17, Htdwl/Bwl=0.7 and Lwl/Htdwl=7.5. 
     
     
         11 . The arrangement according to  claim 3 , characterised by the following ratios for a water line length (Lwl) in the range of 150-180 metres: Bwl/Tdwl=3.5, Lwl/Bwl=5.5, Lwl/Tdwl=20, Htdwl/Bwl=0.55 and Lwl/Htdwl=10.5. 
     
     
         12 . The arrangement according to  claim 3 , characterised by the following ratios for a water line length (Lwl) in the range of 180-210 metres: Bwl/Tdwl=4, Lwl/Bwl=6, Lwl/Tdwl=22, Htdwl/Bwl=0.45 and Lwl/Htdwl=13.5. 
     
     
         13 . The arrangement according to  claim 3 , characterised by the following ratios for a water line length (Lwl) in the range of 210 metres and above: Bwl/Tdwl=5, Lwl/Bwl=10, Lwl/Tdwl=23, Htdwl/Bwl=5 and Lwl/Htdwl=15. 
     
     
         14 . (canceled)