Wave Deflector Air Lubrication System
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing air lubrication systems increase drag on a vessel's hull when not in operation and are susceptible to debris entering the air cavity, while requiring a larger volume of air for effective water expulsion.
Innovation Solution
An air lubrication system with a wave deflector having a planar bottom surface that covers at least 85% of the opening, positioned close to the interface plane, and a gap between the deflector and sidewalls to minimize water entry and debris lodging, with an air inlet in the top wall for efficient air mixing and bubble formation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the air cavity opening is left open to facilitate air injection and water expulsion during operation, then air bubble formation is efficient, but debris can enter and lodge in the cavity when the system is not in operation
Solution Approach 1:
A wave deflector is introduced as an intermediary element between the opening and the air cavity interior. The deflector has a planar bottom surface that covers at least 85% of the opening area when projected onto the interface plane, acting as a selective barrier that allows air to pass through the gaps while blocking debris from entering the cavity when the system is not in operation.
Solution Approach 2:
The wave deflector creates different functional zones: the covered area (at least 85% of opening) provides protection against debris entry, while the gaps between the deflector and sidewalls maintain air injection capability during operation. This local differentiation of function resolves the contradiction between protection and operational efficiency.
2Object-generated harmful factors
If the wave deflector covers most of the opening to reduce drag and prevent debris entry, then the hull drag is reduced and debris is blocked, but the volume of air required for water expulsion increases
Solution Approach 1:
The wave deflector covers at least 85% but not 100% of the opening area, leaving deliberate gaps between the deflector and the sidewalls. This partial coverage is sufficient to reduce drag and block debris while maintaining adequate air flow paths for water expulsion, avoiding the excessive air volume requirement that would result from complete coverage.
3Object-generated harmful factors
If the wave deflector is positioned close to the interface plane to minimize water entry, then water entry is reduced and drag is minimized, but the gap for air injection is reduced
Solution Approach 1:
The wave deflector is positioned in the vertical dimension close to the interface plane (within 2-15 cm) to minimize water entry and drag, while the horizontal gaps between the deflector and sidewalls provide adequate air injection paths. This spatial arrangement in multiple dimensions resolves the apparent contradiction between water exclusion and air injection.
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
Reduces drag on the hull when the system is off, minimizes debris entry, and allows efficient air bubble formation with a smaller air volume, enhancing propulsion efficiency and stability.
Implementation Method 1
a wave deflector having a planar bottom surface which faces said interface plane and extends substantially parallel thereto and is arranged in said air cavity at a distance of 2-15 cm from the interface plane, wherein said bottom surface has a peripheral edge that is spaced apart from said sidewalls by a gap having a width of 0.5-15 cm, wherein, when viewed in projection onto a plane in which said planar bottom surface extends, at least 85% of the area of said opening is covered by said wave deflector
Implementation Method 2
Air is injected into the cavity at such a rate that the water level in the cavity is kept substantially at the level of the hull of the vessel. Due to the forward movement of the vessel, the air in the cavity will move relative to the water at the speed at which the vessel is moving, or seen from the cavity, the water will flow past the cavity at that speed. This difference in velocity between the air and the water causes a so-called Kelvin Helmholtz Instability (KHI) which results in a mixing of air and water at the interface between the water and the air, and in a consequential generation of a layer of small sized air bubbles.
Implementation Method 3
In operation, the deflector effectively shields the air-filled cavity from water entry due to waves and roll motions of the vessel, the elongate deflector part keeping the water surface inside the cavity stable during roll motions
Data Source
AI summary
Disclosed is a system for providing an air lubricating layer between the hull of a vessel and the water flowing under the hull as the vessel is moving through the water, including an air cavity and a wave deflector having a planar bottom surface which faces the interface plane and extends parallel thereto and is arranged in an air cavity of the air lubrication system at a distance of 2-15 cm from the interface plane, wherein the bottom surface has a peripheral edge that is spaced apart from the sidewalls by a gap having a width of 0.5-15 cm, wherein, when viewed in projection onto a plane wherein the planar bottom surface extends, at least 85% of the area of the opening is covered by the wave deflector and/or the planar bottom surface thereof, more preferably at least 90%, and most preferably at least 95%.