V-Shaped Air-Supported Hull Keel Steps for Leakage and Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing air-supported vessels face challenges with air leakage from the air-supported chamber, directional stability, and high hydrodynamic turning resistance moments, which affect their efficiency and environmental sustainability.
Innovation Solution
The design features a V-shaped hull with a discontinuous transition between the keel steps and the bow step, reducing air leakage and enhancing directional stability by improving load distribution and reducing hydrodynamic resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If a deep longitudinal keel is used on starboard and port sides, then directional stability is improved, but hydrodynamic turning resistance moment and drag increase significantly
Solution Approach 1:
The keel structure is segmented into three distinct parts: a transverse bow step at the front, longitudinal keel steps extending backward from the bow step, and a transverse stern step at the rear. This segmentation allows each keel component to perform its specific function - the bow step provides directional stability, the longitudinal keel steps reduce air leakage, and the stern step completes the boundary - while minimizing overall hydrodynamic resistance compared to a single deep longitudinal keel.
Solution Approach 2:
The keel structure transitions from a two-dimensional longitudinal profile to a three-dimensional configuration with both transverse and longitudinal components. The bow step and stern step create transverse dimensions that work together with the longitudinal keel steps to form a comprehensive air boundary system, improving stability and reducing resistance through spatial optimization.
2Force
If high-pressure air is used to lift the hull out of the water, then lifting force is improved, but energy consumption increases significantly
Solution Approach 1:
The patent converts the potentially harmful effect of air leakage into a beneficial design feature by strategically positioning keel steps to control and minimize leakage in a predictable manner. The longitudinal keel steps create controlled air discharge paths that maintain the air cushion while reducing the energy required to sustain it, transforming air loss from a disadvantage into a manageable aspect of the air cushion system.
3Stability of the object's composition
If an inflatable skirt is used around the hull, then air cushion boundary is improved, but stability is reduced when pressure drops
Solution Approach 1:
Different parts of the air boundary system are given different qualities and functions. The inflatable skirt provides flexibility and seals the perimeter, while the rigid keel steps at the bottom provide structural stability and controlled air discharge paths. This local differentiation of qualities allows the system to maintain stability even when pressure fluctuates, as the keel steps provide a stable geometric reference independent of pressure.
Data Source
Figure 0
Figure 1a
Figure 1b
AI summary
An air supported vessel comprising a basically V-shaped hull with a starboard keel part and a port keel part and with a V-shaped bow, which includes an outer bow support surface, where the basically V-shaped hull has at least one air cushion chamber in a substantial part of the basically V-shaped hull's length below the waterline, and where the air supported chamber is delimited by an air supported chamber ceiling, air supported chamber starboard and port side walls and with at least one aft closing device with an aft threshold that forms an aft delimitation of the air supported chamber and with at least an air supported chamber air intake which, together with the side wall of the air supported chamber in the bow, forms the front delimitation of the air supported chamber.