[Problem] There is provided an exhaust system capable of sufficiently exhausting a fuel leakage gas leaked from a marine internal combustion engine without diffusing the fuel leakage gas into an engine room. [Solution] An exhaust system according to an aspect of the present disclosure includes: an exhaust duct provided above a marine internal combustion engine installed in an engine room of a ship; and a suction fan that sucks a fuel leakage gas leaking from the marine internal combustion engine into the inside of the exhaust duct from an engine upper unit side of the marine internal combustion engine. The exhaust duct exhausts the fuel leakage gas sucked by the suction fan to the outside of the engine.

[Problem] There is provided an exhaust system capable of sufficiently exhausting a fuel leakage gas leaked from a marine internal combustion engine without diffusing the fuel leakage gas into an engine room. [Solution] An exhaust system according to an aspect of the present disclosure includes: an exhaust duct provided above a marine internal combustion engine installed in an engine room of a ship; and a suction fan that sucks a fuel leakage gas leaking from the marine internal combustion engine into the inside of the exhaust duct from an engine upper unit side of the marine internal combustion engine. The exhaust duct exhausts the fuel leakage gas sucked by the suction fan to the outside of the engine.

A ventilator for exhausting gas from an exhaust port, by utilizing wind or relative wind around and through the ventilator to create a reduced pressure zone at an open exhaust port. Tapered intermediate portions extend from the opposite ends of a centrally located throat portion within a body of the ventilator to a pair of opposite mouths through which gas can flow out through the ventilator from the exhaust port. Each mouth of the ventilator has an opening with an area significantly larger than the area of a flow path within the throat portion. The throat portion may be of constant internal cross-sectional area over its entire length.

A ventilator for exhausting gas from an exhaust port, by utilizing wind or relative wind around and through the ventilator to create a reduced pressure zone at an open exhaust port. Tapered intermediate portions extend from the opposite ends of a centrally located throat portion within a body of the ventilator to a pair of opposite mouths through which gas can flow out through the ventilator from the exhaust port. Each mouth of the ventilator has an opening with an area significantly larger than the area of a flow path within the throat portion. The throat portion may be of constant internal cross-sectional area over its entire length.

A marine vessel including a hull extending horizontally from a bow to a stern with a midpoint therebetween. The hull has opposing walls that extend upwardly, where the opposing walls have inner sides that face inwardly toward each other and outer sides that face outwardly. A first of the outer sides defines a first opening therein that is horizontally closer to the midpoint than to the stern and horizontally closer to the midpoint than to the bow. An engine compartment is configured for positioning an engine therein. A first conduit fluidly couples the first opening and the engine compartment for at least one of ventilating and exhausting the engine compartment. The first opening is positioned to prevent water from entering the first conduit.

A marine vessel including a hull extending horizontally from a bow to a stern with a midpoint therebetween. The hull has opposing walls that extend upwardly, where the opposing walls have inner sides that face inwardly toward each other and outer sides that face outwardly. A first of the outer sides defines a first opening therein that is horizontally closer to the midpoint than to the stern and horizontally closer to the midpoint than to the bow. An engine compartment is configured for positioning an engine therein. A first conduit fluidly couples the first opening and the engine compartment for at least one of ventilating and exhausting the engine compartment. The first opening is positioned to prevent water from entering the first conduit.

A watercraft includes a deck and a hull having a transom, right and left side portions a tunnel, and a bottom portion. An air intake system disposed in the engine compartment and fluidly communicating with an engine includes an air compressor and an intercooler. The intercooler includes a housing having a lower surface extending generally along the bottom hull portion, an upper surface extending thereabove, an intercooler air inlet, an intercooler air outlet spaced from the intercooler air inlet at least in a direction parallel to the lower surface, a water inlet, and a water outlet. An intercooler core enclosed within the housing defines at least one air channel fluidly communicating with the intercooler air inlet and the intercooler air outlet. At least one water channel fluidly communicating with the water inlet and outlet is diathermally connected with the at least one air channel for cooling air flowing therein.

A watercraft includes a deck and a hull having a transom, right and left side portions a tunnel, and a bottom portion. An air intake system disposed in the engine compartment and fluidly communicating with an engine includes an air compressor and an intercooler. The intercooler includes a housing having a lower surface extending generally along the bottom hull portion, an upper surface extending thereabove, an intercooler air inlet, an intercooler air outlet spaced from the intercooler air inlet at least in a direction parallel to the lower surface, a water inlet, and a water outlet. An intercooler core enclosed within the housing defines at least one air channel fluidly communicating with the intercooler air inlet and the intercooler air outlet. At least one water channel fluidly communicating with the water inlet and outlet is diathermally connected with the at least one air channel for cooling air flowing therein.

A watercraft and method for operating the watercraft, wherein the watercraft includes an electrical system that is present in a space that has an atmosphere that differs from air, where the space is formable by a pressure hull, where the atmosphere contains, for example, an inert gas, and where the space having the electrical system is filled with the atmosphere.

A watercraft and method for operating the watercraft, wherein the watercraft includes an electrical system that is present in a space that has an atmosphere that differs from air, where the space is formable by a pressure hull, where the atmosphere contains, for example, an inert gas, and where the space having the electrical system is filled with the atmosphere.