Ship Frictional Resistance Reduction via Dynamic Bubble Injection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing frictional resistance reduction devices for vessels face challenges in effectively controlling gas injection conditions, particularly under navigational disturbances and varying vessel conditions, leading to inefficient propulsive performance and potential environmental pollution from exhaust gases.
Innovation Solution
A frictional resistance reduction device that includes a gas outlet system with navigational condition detection and control mechanisms, utilizing pressurized gas or exhaust gas from a turbocharger to inject bubbles at the vessel's bottom, optimizing bubble injection based on detected conditions to minimize frictional resistance without affecting the main engine's operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If microbubbles with diameter of several hundred μm or less are injected to the bottom of the vessel, then frictional resistance reduction effect is achieved, but bubbles are easily diffused due to small buoyancy and susceptive to disturbances
Solution Approach 1:
The patent changes the bubble diameter parameter from microbubble scale (several hundred μm or less) to larger bubbles (several mm or more), which fundamentally alters the buoyancy characteristics and stability in turbulent flows, resolving the contradiction between frictional resistance reduction and bubble stability
Solution Approach 2:
The patent implements dynamic control of bubble injection based on detected navigational conditions (waves, currents, vessel attitude), adjusting injection parameters in real-time to maintain optimal bubble performance under varying operational conditions
2Object-affected harmful factors
If bubbles are injected from underwater sides of the vessel overcoming water pressure, then frictional resistance is reduced, but power consumption increases for generating bubbles
Solution Approach 1:
The patent utilizes exhaust gas from the vessel's own engine as the bubble generation source, converting a waste product into a useful resource for frictional resistance reduction, thereby eliminating the need for separate power-consuming bubble generation systems
Solution Approach 2:
The patent converts exhaust gas, which would otherwise be discharged into the atmosphere causing environmental pollution, into bubbles injected into water for frictional resistance reduction, simultaneously achieving environmental protection and energy savings
3Use of energy by moving object
If exhaust gas is used for generating bubbles, then energy saving is achieved, but environmental pollution from exhaust gases may occur
Solution Approach 1:
The patent converts exhaust gas, which would otherwise be discharged into the atmosphere causing environmental pollution, into bubbles injected into water for frictional resistance reduction, simultaneously achieving environmental protection and energy savings
4Ease of operation
If bubble injection is performed without controlling inject conditions, then simple operation is maintained, but propulsive efficiency is reduced and environmental pollution occurs
Solution Approach 1:
The patent implements a feedback control system that detects navigational conditions (waves, currents, vessel attitude) and uses this information to automatically adjust bubble injection parameters, optimizing propulsive efficiency while maintaining automated operation
Solution Approach 2:
The patent integrates multiple functions into the bubble injection system: frictional resistance reduction, propulsive efficiency optimization, and environmental protection through controlled exhaust gas utilization, achieving multiple benefits through a unified system
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 device achieves efficient frictional resistance reduction by accurately controlling bubble injection, maintaining propulsive efficiency, and reducing energy consumption, while preventing environmental pollution and ensuring safe operation.
Implementation Method 1
a gas outlet (13) injecting bubbles at least to a bottom of the vessel
Implementation Method 2
optimizing bubble injection based on detected conditions to minimize frictional resistance
Data Source
Figure 1(a)~1(c)
Figure 2(a)~2(c)
Figure 3
AI summary
A inject gas control device that performs, for example, control reflecting variation in vessel velocity over time without adversely affecting the main engine is realized. That is, it is prevented that gas is drawn too much and thereby a gas supply or charged air rate becomes insufficient, efficiency of the main engine is decreased and exhaust gas is deteriorated, and analogous events occur because the gas supply or charged air rate is too much instead. There are provided a main engine 4010 acquiring propelling power for a vessel 1, and a turbocharger 4011 that is driven by exhaust gas from the main engine 4010 and blows pressurized gas to the main engine 4010. A part of the pressurized gas and/or exhaust gas is drawn from between the turbocharger 4011 and the main engine 4010 (5023, 5024 and 5025). The drawn pressurized gas and/or exhaust gas are injected in the proximity 9 of the hull on or below the waterline (5040), and the drawing rate of the pressurized gas and/or the exhaust gas is controlled on the basis of a physical quantity related to a heat load on the main engine 10 and characteristics of the turbocharger (4200).