Submerged exhaust discharge for marine vessel

Abstract

A marine exhaust system adapted for discharging marine exhaust below the water line through at least one streamlined conformal discharge fitting attached to the vessel hull. Each discharge fitting comprises a low profile body attached to the vessel hull in relation with an exhaust discharge conduit terminating in a thru-hull opening so as to discharge marine exhaust into the discharge fitting body. The discharge fitting preferably includes a forward end and an aft end connecting a main discharge fitting body disposed in spaced relation with the underside of the vessel hull. The discharge fitting body defines an exhaust outlet disposed on outboard side thereof so as to allow exhaust gas to exit in an outward and aft flow such that corrosive exhaust gas does not flow over the vessel propellers. Forward and aft baffles are disposed within the discharge fitting body to direct and re-direct exhaust gas flow. By maintaining a streamlined and low-profile/conformal shape, reduction in overall hull hydrodynamics due to increased drag is minimized.

1 . An exhaust discharge fitting for use with a marine vessel, said vessel having a hull with a bottom that is at least partially submerged below the water line when the vessel is buoyantly disposed within a body of water and an exhaust system configured to discharge exhaust below the water line via a thru-hull opening, said hull bottom sloping from the centerline upward and laterally outward in starboard and port directions reaching the hull chine wherein the bottom and sides of the hull meet, said hull terminating forwardly at the bow and rearwardly at the stern, said exhaust discharge fitting comprising:
 an exhaust discharge structure attached to the bottom of the vessel hull;   said structure including a mid-portion disposed between fore and aft end portions and inboard and outboard side edges;   said mid-portion in spaced relation with the vessel hull so as to define a gas diffuser chamber;   said structure attached to the bottom of the vessel hull in relation to the thru-hull opening such that exhaust gas exiting the thru-hull opening flows into said gas diffuser chamber;   said fore end potion tapering from said mid-potion toward the hull and terminating at a peripheral edge in fluid tight engagement with the hull;   said mid-potion tapering toward said hull in an inboard direction and terminating at an inboard side edge in fluid tight engagement with the hull;   said aft end potion tapering from said mid-portion toward the hull and terminating at a peripheral edge in fluid tight engagement with the hull;   said outboard side edge having a portion thereof in spaced relation with the hull and recessed inwardly relative to said fore end portion to define an exhaust gas outlet to allow exhaust gas to escape from said gas diffuser chamber in a generally outboard and aft direction.   
   
   
       2 . An exhaust discharge fitting for use with a marine vessel according to  claim 1 , further including a forward baffle extending laterally across said structure from inboard to outboard sides thereof in proximity to fore end, said forward baffle having an upper end in conforming contact with the bottom of the hull and a lower end conformingly affixed to main body. 
   
   
       3 . An exhaust discharge fitting for use with a marine vessel according to  claim 1 , further including an aft baffle extending laterally across said structure from inboard to outboard sides thereof in proximity to aft end, said aft baffle having an upper end in conforming contact with the bottom of the hull and a lower end conformingly affixed to main body. 
   
   
       4 . A submerged exhaust discharge fitting for use with a marine vessel, said vessel having a hull with a bottom that is at least partially submerged below the water line when the vessel is buoyantly disposed within a body of water and an exhaust system configured to discharge exhaust below the water line via a thru-hull opening, said hull bottom sloping from the centerline upward and laterally outward in starboard and port directions reaching the hull chine wherein the bottom and sides of the hull meet, said hull terminating forwardly at the bow and rearwardly at the stern, said exhaust discharge fitting comprising:
 a hydrodynamic exhaust discharge fitting convexly projecting from the bottom of the vessel hull;   said structure including a mid-portion disposed between fore and aft end portions and inboard and outboard side edges;   said mid-portion in spaced relation with the vessel hull so as to define a gas diffuser chamber;   said structure attached to the bottom of the vessel hull in relation to the thru-hull opening such that exhaust gas exiting the thru-hull opening flows into said gas diffuser chamber;   said fore end potion tapering from said mid-potion toward the hull and terminating at a peripheral edge in substantially flush fluid tight engagement with the hull;   said mid-potion tapering toward said hull in an inboard direction and terminating at an inboard side edge in substantially flush fluid tight engagement with the hull;   said aft end potion tapering from said mid-portion toward the hull and terminating at a peripheral edge in substantially flush fluid tight engagement with the hull;   said outboard side edge having a portion thereof in spaced relation with the hull and recessed inwardly relative to said fore end portion to define an exhaust gas outlet to allow exhaust gas to escape from said gas diffuser chamber in a generally outboard and aft direction.   
   
   
       5 . An exhaust discharge fitting for use with a marine vessel according to  claim 4 , further including a forward baffle extending laterally across said structure from inboard to outboard sides thereof in proximity to fore end, said baffle having an upper end in conforming contact with the bottom of the hull and a lower end conformingly affixed to main body. 
   
   
       6 . An exhaust discharge fitting for use with a marine vessel according to  claim 4 , further including an aft baffle extending laterally across said structure from inboard to outboard sides thereof in proximity to aft end, and further extending along said outboard side edge, said aft baffle having an upper end in conforming contact with the bottom of the hull and a lower end conformingly affixed to main body.