Abstract: Disclosed is a vessel including a hull and a system providing an air lubricating layer between the bottom and water, including a cavity defined by sidewalls, a top wall and an interface plane, in which water mixes with air due the Kelvin Helmholtz effect. The sidewalls extend from a dagger-shaped nose section at the front end to the rear end of the cavity and diverge so a distance between the sidewalls increases along the length of the cavity when going in a rearward direction. The diverging cavities provide a stable air lubrication layer that covers a relatively large area of the bottom, so the number of cavities can be reduced. The alignment of the diverging cavities with the streamlines has relatively large tolerances so construction is simplified and can be carried out in a cost-effective manner. The diverging sidewalls lead to reduced formation of vortices and reduced drag.

Abstract: Disclosed is a system for providing an air lubricating layer between the hull of a vessel and the water flowing under the hull as the vessel is moving through the water, including an air cavity and a wave deflector having a planar bottom surface which faces the interface plane and extends parallel thereto and is arranged in an air cavity of the air lubrication system at a distance of 2-15 cm from the interface plane, wherein the bottom surface has a peripheral edge that is spaced apart from the sidewalls by a gap having a width of 0.5-15 cm, wherein, when viewed in projection onto a plane wherein the planar bottom surface extends, at least 85% of the area of the opening is covered by the wave deflector and/or the planar bottom surface thereof, more preferably at least 90%, and most preferably at least 95%.

Abstract: Disclosed is a dual cavity air lubrication system including an air flow splitter with an air inlet pipe branching into a first branch pipe and a second branch pipe, wherein a first passive valve is arranged in the first branch pipe and a second passive valve is arranged in the second branch pipe, wherein the branch pipes are in fluid communication with each other upstream from their respective valves, and wherein the valves are adapted for regulating the flow of air to respective air cavities to compensate for difference in air pressure in the cavities caused by a relative change in level of the cavities due to roll or heel of the vessel.

Abstract: The invention relates to a system for providing an air lubricating layer between the hull of a vessel and the water flowing under the hull as said vessel is moving through the water, comprising an air cavity and a wave deflector having a planar bottom surface which faces said interface plane and extends parallel thereto and is arranged in an air cavity of said air lubrication system at a distance of 2-15 cm from the interface plane, wherein said bottom surface has a peripheral edge that is spaced apart from said sidewalls by a gap having a width of 0.5-15 cm, wherein, when viewed in projection onto a plane wherein said planar bottom surface extends, at least 85% of the area of said opening is covered by said wave deflector and/or said planar bottom surface thereof, more preferably at least 90%, and most preferably at least 95%.

Abstract: A method for reducing marine growth on a vessel, includes providing an air lubrication system and covering at least a part of the hull with air bubbles. Also described is a vessel having an air lubricating system with releasable connection of the deflectors across the cavity, a closeable outlet valve in the air outlet duct, connection of a compressor to each cavity or pair of cavities and an air inlet opening in the top of the cavity.

Abstract: A method for reducing marine growth on a vessel, includes providing an air lubrication system and covering at least a part of the hull with air bubbles. Also described is a vessel having an air lubricating system with releasable connection of the deflectors across the cavity, a closeable outlet valve in the air outlet duct, connection of a compressor to each cavity or pair of cavities and an air inlet opening in the top of the cavity.

Abstract: A system for providing an air lubricating layer between a substantially flat bottom (3) of a vessel (1) and the water flowing under the bottom as the vessel is moving through the water, whereby the system includes sidewalls (5,5?) and a top wall (4) defining a cavity (6) with an opening (13) situated in an interface plane that is transversal to the sidewalls (5,5?), at the level of the flat bottom (3), the opening having a front end (9) and a rear end (15) seen in the length direction of the cavity, an air inlet (10) spaced from the opening for introducing air into the cavity, whereby the length of the opening (13) of the cavity (6) is between 2 and 10 m and the distance (H) of the top wall (4) from the interface plane is between 0.2 m and 0.5 m.

Abstract: A method for reducing marine growth on a vessel, includes providing an air lubrication system and covering at least a part of the hull with air bubbles. Also described is a vessel having an air lubricating system with releasable connection of the deflectors across the cavity, a closeable outlet valve in the air outlet duct, connection of a compressor to each cavity or pair of cavities and an air inlet opening in the top of the cavity.

Abstract: A system for providing an air lubricating layer between a substantially flat bottom (3) of a vessel (1) and the water flowing under the bottom as the vessel is moving through the water, whereby the system includes sidewalls (5,5?) and a top wall (4) defining a cavity (6) with an opening (13) situated in an interface plane that is transversal to the sidewalls (5,5?), at the level of the flat bottom (3), the opening having a front end (9) and a rear end (15) seen in the length direction of the cavity, an air inlet (10) spaced from the opening for introducing air into the cavity, whereby the length of the opening (13) of the cavity (6) is between 2 and 10 m and the distance (H) of the top wall (4) from the interface plane is between 0.2 m and 0.5 m.

Abstract: A system for providing an air lubricating layer between a substantially flat bottom (3) of a vessel (1) and the water flowing under the bottom as the vessel is moving through the water, whereby the system includes sidewalls (5,5?) and a top wall (4) defining a cavity (6) with an opening (13) situated in an interface plane that is transversal to the sidewalls (5,5?), at the level of the flat bottom (3), the opening having a front end (9) and a rear end (15) seen in the length direction of the cavity, an air inlet (10) spaced from the opening for introducing air into the cavity, whereby the length of the opening (13) of the cavity (6) is between 2 and 10 m and the distance (H) of the top wall (4) from the interface plane is between 0.2 m and 0.5 m.

Abstract: A system for providing an air lubricating layer between a substantially flat bottom (3) of a vessel (1) and the water flowing under the bottom as the vessel is moving through the water, whereby the system includes sidewalls (5,5?) and a top wall (4) defining a cavity (6) with an opening (13) situated in an interface plane that is transversal to the sidewalls (5,5?), at the level of the flat bottom (3), the opening having a front end (9) and a rear end (15) seen in the length direction of the cavity, an air inlet (10) spaced from the opening for introducing air into the cavity, whereby the length of the opening (13) of the cavity (6) is between 2 and 10 m and the distance (H) of the top wall (4) from the interface plane is between 0.2 m and 0.5 m.

Abstract: The invention concern device placed in a fishing trawl for sorting out marine species not to be caught. The device is inserted in the after part of the trawl, near the trawl bag. The device is a venturi-type narrowing (2) comprising outslip unit (11) being placed in front end of the narrowing, forming a part of the trawl. The outslip unit allows selection of marine species not to be caught. The fish to escape is directed towards the outslip unit (11).