A frictional resistance-reducing device and a ship including the same are disclosed. The ship comprises: an outer panel including and air outlet; a plurality of reinforcement members provided on the inner surface of the outer panel so as to be spaced from each other; and a frictional resistance-reducing device formed on the inner surface of the out panel between immediately neighboring reinforcement members among the plurality of reinforcement members, so as to cover the air outlet, wherein the frictional resistance-reducing device includes: a hollow housing of which one surface is opened; and an air inlet formed in the houseing, and the opened one surface faces the air outlet.

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.

Disclosed is an air supply system for supplying air to an outside of a hull of a vessel, the vessel holding a combustion engine. The air supply system comprises one or more air discharge units (ADUs) for releasing compressed air to an outside of the hull below a waterline of the vessel. The air supply system comprises a plurality of turbocharger(s) for supplying a compressed air flow to the combustion engine of the vessel via a first flow path. The plurality of turbochargers each comprises a turbine configured to be driven by an exhaust gas flow of the combustion engine and a compressor connected to the turbine and comprising an inlet for receiving air and an outlet for providing the compressed air flow to the first flow path. The plurality of turbochargers comprises a first turbocharger and a second turbocharger arranged in series with the compressor of the second turbocharger being downstream of the compressor of the first turbocharger in the first flow path. The air supply system comprises a first sub-path and a second sub-path branching off the first flow path and supplying the sub-flow of air to the ADUs. The first sub-path branches off from the first flow path downstream of the first turbocharger and upstream of the second turbocharger and wherein the second sub-path branches off from the first flow path downstream of both the first turbocharger and the second turbocharger.

A vessel (1) has at least three cavities that are distributed across the bottom in the length direction along a line extending from the center line near the bow, to a respective side. Furthermore, the vessel accommodates for each cavity or pair of cavities on opposite sides of the center line at a predetermined length position, a corresponding compressor for injecting air into the cavity at a pressure substantially corresponding to the hydrostatic pressure in each cavity. Each cavity (33) may include a deflector that has an elongate part (29, 34, 34) extending in the length direction of the cavity over at least at least 5%, preferably at least 10% of the cavity length L. An air inlet opening (23) may be provided in the top wall (19).

A vessel configured for transporting cargo can be configured to operate in a supercavitation mode, the supercavitation mode including releasing a fluid at least partially over an external surface, diverting at least a portion of the fluid to a propulsion system, and generating propulsion at least in part from the first fluid. In response to traveling in the supercavitation mode, the vessel can travel at high-speeds with a majority of the hull below a surface of a body of water.

A foam release apparatus for use in conjunction with a vessel air lubrication system has a chamber intersected by and in fluid communication with the air lubrication system return pipe and one or more sloped release channels formed within the lower portion of the chamber opposite the return pipe chamber inlet, each release channel terminating in a respective release slot formed in the vessel hull so as to fluidly communicate between the chamber and the water boundary layer beneath the hull via the release channels and release slots.

A system (16) for providing an air lubricating layer between a substantially flat bottom (6) of the hull (4) of a vessel (1) and water flowing under the bottom as the vessel is moving through the water. The system has a cavity (33) with a deflector. The deflector has an elongate part (29,34,34) extending in the length direction of the cavity over at least at least 5%, preferably at least 10% of the cavity length L, wherein a projected area of the at least one deflector member (24,24-26,26) on the interface plane (30) covers at least 25%, preferably at least 50%, most preferably at least 75% of the surface area of the interface plane.

This present invention is a more economical method and apparatus for compressing gas or other compressible fluids in high volumes at any desired pressures for any desired purpose. One preferred use is for generating high volumes of air capable to be delivered at any drafts for the purpose of lubricating ships motions and accordingly lowering their drag, fuel consumption and harmful emissions.

The present invention relates to a surface cover for a body which can be brought into contact with a liquid, comprising: a layer which at least partly contains gas and which is designed and arranged such that at least some sections of a layer face facing the liquid contacts the liquid; a gas-permeable layer which is arranged on the gas-containing layer on a face that faces the body and is opposite the face facing the liquid or which is integrally formed with the gas-containing layer; and a gas-supplying device which is connected to the gas-permeable layer such that gas can flow from the gas-supplying device to the gas-containing layer through the gas-permeable layer. The invention also relates to an arrangement and a use.

A vessel configured for transporting cargo can be configured to operate in a supercavitation mode, the supercavitation mode including releasing a fluid at least partially over an external surface, diverting at least a portion of the fluid to a propulsion system, and generating propulsion at least in part from the first fluid. In response to traveling in the supercavitation mode, the vessel can travel at high-speeds with a majority of the hull below a surface of a body of water.