Multihull Ship Wing Superstructure Inversion for Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Classic analysis of marine vessels with passive partial aerodynamic lift is based on linear models valid for low pitch angles, leading to instability at larger angles, potentially causing flipping or sinking due to changes in aerodynamic lift with external disturbances like wind or waves.
Innovation Solution
A marine-powered multihull vessel design with a superstructure that generates significant aerodynamic lift, where the point of application of lift is positioned behind the center of gravity, and the hydrodynamic forces' resultant is applied forward, ensuring intrinsic stability and efficient speed, reducing energy consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If the point of application of aerodynamic lift is placed in front of the center of gravity (classic configuration), then the vessel can achieve aerodynamic lift, but the vessel becomes unstable at larger pitch angles, potentially leading to flipping or sinking
Solution Approach 1:
The patent inverts the classic configuration by placing point A (application of aerodynamic lift) behind the center of gravity G, rather than in front as traditionally done. This inversion fundamentally changes the stability characteristics: when the vessel pitches up, the angle of attack decreases and lift decreases, creating a restoring moment. Similarly, when the vessel dives, the angle of attack increases and lift increases, preventing sinking. This inverse positioning resolves the instability problem while maintaining aerodynamic lift effectiveness.
2Speed
If the vessel operates at higher speeds to benefit from greater aerodynamic lift, then progress resistance increases and energy consumption increases, but stability is compromised
Solution Approach 1:
The patent implements a natural feedback mechanism through the inverted configuration of point A relative to point G. When external disturbances (wind shifts, waves) cause pitch deviations, the resulting change in angle of attack automatically adjusts the aerodynamic lift to counteract the disturbance. This passive feedback stabilizes the vessel at higher speeds without requiring active control systems, enabling the vessel to operate efficiently at cruising speeds of 40-70 knots with reduced energy consumption compared to traditional configurations.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The design enhances stability, allowing faster sailing with greater aerodynamic lift, reducing progress resistance and energy consumption, while maintaining safety by stabilizing pitch and heaving movements.
Implementation Method 1
the superstructure of the vessel forming a wing capable of passively generating significant aerodynamic lift, i.e. between 20 and 90%, preferably between 35% and 90%, of the total weight of the vessel at a cruising speed of the vessel
Implementation Method 2
point H of application of the resultant of the hydrodynamic forces being consequently necessarily behind point G
Data Source
Figure 1~2
Figure 3~5
Figure 6~7
AI summary
This ship (10), which has a length-to-width ratio of less than two, comprises a superstructure and at least two hulls, the superstructure forming a wing capable passively of generating aerodynamic lift of between 20 and 90% of the weight of the ship at a cruising speed thereof, the wing comprising curved ends connected to each of the hulls and having an extrados developed surface area substantially equal to the product of the length times the width of the ship. It is characterized in that a point A of application of the aerodynamic lift generated by the superstructure (12) is situated to the rear of the centre of gravity G at which the forces of gravity are applied to the ship, a point H at which the resultant of the hydrodynamic loads generated by the hulls (50, 60) is applied being situated forward of the centre of gravity G.