Wave piercing bow of a monohull marine craft

Abstract

This invention provides an improved shape of the bow of a high speed ocean-going ship. It introduces a set of inverted and inclined surfaces that enclose the bow from above, and cause the hull to move through the waves rather than over them. These surfaces generate a downward lifting force that counteracts the displacement force. Displacement force causes a traditionally-shaped bow to lift above waves and initiate pitching movement. The new type of bow reduces or eliminates pitching movement and slamming loads on the hull, thus improving ride quality, and enabling designers to specify lighter structure under the existing rules. This in turn reduces the overall weight of the craft, enabling reduction in the power required to achieve the service speed, reduction in fuel consumption, and reduction in the associated capital and operating costs. It also improves ride quality for passengers, and reduces damage to cargo due to accelerations. U.S. Prior Application References 5,184,561 July 1993 Nickell 5,263,433 November 1993 Meyer 6,116,180 September 2000 Thompson Foreign Prior Application References 2,359,532 November 2001 Canada 2,150,890 July 1985 United Kingdom 2,230,717 April 1991 United Kingdom 02,296,855 June 1992 Japan 05,277,190 May 1995 Japan

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:  
     
         1 . A sea-going ship's hull form, in which the bow is enclosed from the top by a surface extending longitudinally from the tip of the bow located at a point vertically closer to the waterline than the deck, to said deck level further aft, said surface also inclined transversely sloping down from the center plane of the hull towards the sides of the hull, said surface having at least half of its area, in which straight lines tangent to the points on longitudinal sections through said half of the area, are at angles of no less than 0 degrees and no more than 30 degrees to horizontal, and in which straight lines tangent to the points on transverse sections through said half of the area, are at angles of no less than 0 degrees and no more than 30 degrees to horizontal.  
     
     
         2 . A sea-going ship's hull form as defined in  claim 1 , in which said top bow enclosing surface has shape symmetrical port and starboard.  
     
     
         3 . A sea-going ship's hull form as defined in  claim 1 , in which shape of said top bow enclosing surface is composed of plurality of panels separated by knuckles.  
     
     
         4 . A sea-going ship's hull form as defined in  claim 1 , in which said top bow enclosing surface has an additional panel having horizontal transverse sections, at the center portion of said top bow enclosing surface.  
     
     
         5 . A sea-going ship's hull form as defined in  claim 1 , in which one or more portions of said top bow enclosing surface is of a conical shape.  
     
     
         6 . A sea-going ship's hull form as defined in  claim 1 , in which one or more portions of said top bow enclosing surface is flat.  
     
     
         7 . A sea-going ship's hull form as defined in  claim 1 , in which shape of said top bow enclosing surface is composed of plurality of panels, some of which are displaced vertically in relation to one another, and joined with additional panels of height not exceeding 10% of the total length of said top bow enclosing surface, and inclined no more than 45 degrees from vertical.  
     
     
         8 . A sea going ship's hull form as defined in  claim 1 , in which said top bow enclosing surface is further twisted below said deck to deflect the flow of water and spray to the sides, away from the hull.  
     
     
         9 . A sea-going ship's hull form as defined in  claim 1 , in which said top bow enclosing surface is fitted with one or several recesses to accommodate mooring and other fittings and/or equipment.