A propulsion system for a marine vessel in a body of water includes an water intake formed in the hull, a impeller disc rotatable about a vertical axis for raising water and increasing the momentum of water in a plenum chamber, and a plurality of control gates located around the periphery of the hull. The impeller disc has a large outer diameter and is formed to enable efficient rotation by an electric motor. One or more of the water intake, the plenum chamber, the impeller disc and the control gates is designed to reduce acoustic noise generated by the marine vessel, direct the acoustic noise to avoid broadband acoustic noise, increase efficiency of the propulsion system and provide additional safety to passengers on the marine vessel and marine life in the body of water.

A built-in propulsion system includes an engine, a diversion unit with a diversion base and an exhaust pipe, and a propulsion unit. The diversion base is connected to the engine, having a water inlet, a water outlet, a diversion channel in communication between the water inlet and the water outlet, a shaft hole above the water inlet and an exhaust chamber behind the shaft hole. The exhaust pipe is fixed on the outer periphery surface of the diversion base in communication with the exhaust chamber. The propulsion unit includes a transmission shaft inserted through the shaft hole and connected to the engine, and an impeller located in the diversion channel and connected to the transmission shaft. The exhaust pipe is used to exhaust the exhaust gas of the engine to the outside of the diversion base to avoid the interference of the exhaust gas and the water flow.

A built-in propulsion system includes an engine, a diversion unit with a diversion base and an exhaust pipe, and a propulsion unit. The diversion base is connected to the engine, having a water inlet, a water outlet, a diversion channel in communication between the water inlet and the water outlet, a shaft hole above the water inlet and an exhaust chamber behind the shaft hole. The exhaust pipe is fixed on the outer periphery surface of the diversion base in communication with the exhaust chamber. The propulsion unit includes a transmission shaft inserted through the shaft hole and connected to the engine, and an impeller located in the diversion channel and connected to the transmission shaft. The exhaust pipe is used to exhaust the exhaust gas of the engine to the outside of the diversion base to avoid the interference of the exhaust gas and the water flow.

A marine vessel having a hull with a pair of opposite sides disposed at an angle with respect to one another, the opposite sides also disposed at an angle with respect to a water surface. A marine propulsion system is operatively coupled to the hull and includes a pair of impellers associated respectively with the pair of hull sides that rotate within respective impeller planes disposed generally parallel to the hull sides to convey water from at least one inlet though at least one outlet to provide thrust to the vessel. The marine propulsion system may also be contained within an outboard unit mounted to a transom of the vessel.

A marine vessel having a hull with a pair of opposite sides disposed at an angle with respect to one another, the opposite sides also disposed at an angle with respect to a water surface. A marine propulsion system is operatively coupled to the hull and includes a pair of impellers associated respectively with the pair of hull sides that rotate within respective impeller planes disposed generally parallel to the hull sides to convey water from at least one inlet though at least one outlet to provide thrust to the vessel. The marine propulsion system may also be contained within an outboard unit mounted to a transom of the vessel.