System and Method for Marine Propulsion With Low Acoustic Noise

A marine vessel comprising:

• a hull comprising an outer surface;
• a water intake formed in the outer surface of the hull in a substantially vertically downward direction;
• an impeller disc rotatable about a vertical axis, the impeller disc comprising:
• a top surface orthogonal to the vertical axis, the top surface extending radially outward to a top surface outer edge;
• and
• a bottom surface separated from the top surface by a distance and extending radially outward to a bottom surface outer edge;
• and
• an angled surface extending between the bottom surface outer edge to the top surface outer edge, the angle surface comprising a plurality of blades;
• a plenum chamber for containing the impeller disc, the plenum chamber comprising
• an upper wall extending radially outward of the top surface outer edge;
• a bottom wall having a bottom wall outer diameter radially inward of the water intake;
• and
• a lower wall extending from the bottom wall radially inward of the water intake to the upper wall to the upper wall radially outward of the water intake, the lower wall having an opening in fluid communication with the water intake;
• a plurality of control gates in fluid communication with the plenum chamber and located near the periphery of the hull;
• and
• a control system configured to:
• rotate the impeller disc to cause water flow from the water intake to the plurality of control gates;
• and
• open one or more of the plurality of control gates, wherein water exiting the one or more of the plurality of control gates flows into the ambient water to generate thrust.