Transonic hull and hydrofield

Abstract

A transonic hull having a bow, a stern, a longitudinal length therebetween, side surfaces extending from the bow to outboard portions of the stern, a lower surface extending between the side surfaces, the transonic hull having a submerged volume with an approximately triangular shape in planview with apex adjacent the bow and a base adjacent the stern, and an approximately triangular shape in side view when in motion with a base adjacent the bow and an apex adjacent the stern.

1 . A vessel having a forward end, a midbody, and a longitudinal length; said vessel having a rearward end, and a lower surface, with said lower surface having an athwarship downstream border; 
 a first movable surface element adjacent and to the rear of said downstream border, said first movable surface having a forward edge with a first articulation on said downstream border, a first rearward edge, and a first longitudinal length therebetween; and    a second movable surface element adjacent and to the rear of said first surface element having an upstream edge with a second articulation on said rearward edge of said first surface element, a second rearward edge, and a second longitudinal length therebetween.    
     
     
         2 . The vessel of  claim 1  further characterized in that the longitudinal length of said second surface element is substantially smaller than the longitudinal length of said first surface element.  
     
     
         3 . The vessel of  claim 2  further characterized in that said second surface element has an upward protrusion, with connecting link means extending between said upward protrusion and said rearward end of said vessel at a vertical location above said downstream border of said lower surface of said vessel.  
     
     
         4 . The vessel of  claim 3  further comprising control means provided to cause angular motion of said first surface element relative to the said lower surface of said vessel.  
     
     
         5 . The vessel of  claim 3  further characterized in that the angular motion of said second surface element relative to said first surface element under the mechanical action of said link is in opposite direction to the angular motion of said first surface element relative to said lower surface of said vessel.  
     
     
         6 . The vessel of  claim 3  further characterized in that the vertical distance between said second articulation and said link is approximately equal to the vertical distance between said first articulation and said link.  
     
     
         7 . The vessel of  claim 3  in which the opposite angular deflections of said first and second elements have approximately equal magnitude.  
     
     
         8 . A vessel having a lower downstream border, a first trailing surface mounted on said lower border with a second surface mounted on and downstream of said first surface; 
 control means connecting said first surface to said vessel and mechanical means connecting said second surface to said vessel;    angular deflection of said first surface caused by said control means generating opposite angular motion of said tab under the action of said mechanical means; and    said opposite angular deflections being of approximately of the same magnitude.    
     
     
         9 . The vessel of  claim 8  in which the ratio of widths of said second surface to said first surface is no greater than approximately 0.20.  
     
     
         10 . A multihull vessel having in combination at least two Transonic Hulls, with each of said transonic hull characterized in having 
 (a) a longitudinal length, a bow, a stern side surfaces and a lower surface;    (b) A hydrostatic waterplane with sides, which are substantially free of shoulder, midbody, and rear quarter curvatures;    (c) A maximum hydrostatic draft adjacent said bow and a maximum beam adjacent said stern;    (d) said maximum beam being substantially larger than said maximum draft;    (e) with each of said hulls having when in forward motion a hydrodynamic regime with a hydrodynamic field having surface rays which extend rearwardly in top view in a generally triangular pattern adjacent the sides of each of said hulls, with apex adjacent the bow of said hulls; and    (f) with the combined hydrodynamic field of said transonic hulls in said hydrodynamic regime being free of mutual interference between said rays within the water region between said transonic hulls.    
     
     
         11 . The vessel of  claim 10  with power means for forward propulsion, which under a first power level, said hydrodynamic field has a supercritical displacement regime in which said underfaces of said hulls have a negative angle relative to the remote waterplane, said undersurface being subjected to propulsive pressure, with wetted side surface areas which generate frictional resistance to forward motion.  
     
     
         12 . The vessel of  claim 11  in which under a higher second power level, said hydrodynamic field has a hypercritical regime in which said underfaces of said hulls have a substantially smaller angle relative to remote waterplane, with reduced wetted side surface areas of said hulls.  
     
     
         13 . The vessel of  claim 12  which under a higher third power level, higher than said second level, said hydrodynamic field has a transplannar regime in which said smaller angle is positive, with said lower surfaces of said hulls having a wetted area portion substantially larger than the remaining lower surface area portion which is generally free of contact with and above local water level.  
     
     
         14 . The vessel of  claim 13  in which rearward surface water flows along, adjacent and generally parallel to the sides of said hulls in said transplannar regime.  
     
     
         15 . A multihull vessel having in combination at least two hulls of approximately equal length, an overall beam, a water region between said hulls, and propulsive means, said vessel being characterized in that (a) each of said hulls has a bow, longitudinal length, a stern, side surfaces, and a beam, (b) with the combined side surface of each of said hulls laterally facing said mid water region forming in plan view the sides of a channel region therebetween, with an intake mouth adjacent said bows of said hulls and a smaller exit mouth adjacent said stern, (c) said propulsive means on said vessel having water impellers located between said hulls, with said impeller means accelerating local flow rearward, (d) with the forward motion of said vessel causing a contracting flow stream in top view within said channel region tending to form a higher surface level which is diminished downwards by said rearwardly accelerated flow generated by said impeller means.  
     
     
         16 . The vessel of  claim 15  in which each of said hulls is a transonic hull having side surfaces which at water level are free of midbody shoulder and quarter curvature, with the outboard side surface of said hulls being substantially parallel to each other which, together with said intake mouth and a total vessel beam adjacent said sterns, define an outer perimeter which is substantially rectangular, and in that the inward side surfaces of said hulls, together with said intake mouth and said exit mouth define an inboard perimeter which is substantially trapezoidal, with the width of said intake mouth being larger than the width of said exit mouth, and with said propulsive means accelerating the flow within said inward perimeter in a rearward direction.