Concave Hull Shape with Inflection Points for Propeller Pump Efficiency

The patent applies curvature by designing the hull with a specific concave shape opposite the pump-propeller, featuring two inflection points and a tangent parallel to the shaft line axis. This curved geometry optimizes fluid flow patterns around the thruster, reducing adverse interactions and improving propulsive efficiency without adding mechanical complexity to the propulsion system itself.

The patent implements local quality by modifying only the specific region of the hull opposite the pump-propeller while leaving the rest of the hull structure conventional. The concave section with defined inflection points creates localized flow optimization exactly where the thruster interacts with the hull, maintaining simplicity elsewhere in the vessel design.

The concave hull shape with its specific curvature and inflection points creates an optimized flow path between the hull and the pump-propeller. This geometric configuration allows the hull to be positioned at an optimal distance that balances thrust generation enhancement with drag reduction, as the curved surface guides fluid flow smoothly around the thruster assembly.

The patent changes the geometric parameters of the hull shape by introducing a concave section with specific characteristics (two inflection points, tangent parallel to shaft line, positioned at distance L < D/4 from the nozzle leading edge). These parameter modifications optimize the interaction between the hull and propeller pump, enhancing thrust while controlling drag through precise geometric control.

The concave hull section with defined inflection points can be manufactured using conventional shipbuilding techniques such as mold construction and plate bending. The curvature is achieved through standard hull forming processes, and the specific geometric features (inflection points, tangent positioning) can be incorporated into the hull template and building blocks without requiring advanced or specialized manufacturing capabilities.

By limiting the optimized concave shape to a localized section of the hull opposite the pump-propeller, the manufacturing complexity is confined to a specific area rather than the entire hull structure. This allows the majority of the hull to be constructed using conventional, simpler methods, while only the critical region requires the more complex curved geometry for energy optimization.