Dynamic Liquid Tank Roll Dampening for Ocean Vessels
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Contemporary passive roll dampening apparatuses in ocean vessels are ineffective due to inadequate monitoring of dynamic characteristics, often exacerbating rolling motions and causing discomfort and stability issues, especially in adverse weather conditions.
Innovation Solution
A roll dampening apparatus with a transversely disposed elongate tank partially filled with liquid, dynamically controlling the effective depth of the liquid to oppose rolling motions by using sensors and an actuated baffle arrangement, and dynamically adjusting the liquid depth by removing or adding liquid to modulate the wave propagation within the tank.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If passive liquid tanks are used for roll dampening, then the apparatus structure is simple, but the rolling motion is not effectively reduced and may even be exacerbated
Solution Approach 1:
The patent transforms the static passive tank system into a dynamic active system by implementing real-time monitoring of liquid wave characteristics and dynamically adjusting tank parameters (such as liquid depth or tank orientation) to maintain optimal counter-phase conditions for roll dampening, thereby resolving the contradiction between structural simplicity and dampening effectiveness
Solution Approach 2:
The patent introduces feedback control mechanisms that continuously monitor the phase relationship between liquid waves and vessel rolling motion, using sensor data to adjust tank operations in real-time, ensuring the liquid wave remains in counter-phase to effectively reduce rolling while maintaining system simplicity
2Reliability
If gyroscopic devices are used to prevent rolling motion, then rolling motion is completely prevented, but high energy input (20 kW) is required
Solution Approach 1:
The patent employs the vessel's own rolling motion to drive the liquid waves in the tanks, converting the harmful rolling energy into useful dampening action through the inertial movement of the liquid, thereby achieving roll reduction without requiring external energy input unlike gyroscopic systems
Solution Approach 2:
The patent utilizes hydraulic principles by employing liquid mass in tanks to create inertial forces that counteract rolling motion, leveraging the physical properties of fluids to achieve stabilization without the high energy consumption associated with mechanical gyroscopic systems
3Productivity
If liquid depth in the tank is increased, then wave propagation is enhanced, but the apparatus becomes less adaptable to varying sea conditions
Solution Approach 1:
The patent implements dynamic adjustment of liquid depth or tank configuration based on real-time sea condition monitoring, allowing the system to optimize wave propagation characteristics for different wave periods and intensities, thereby maintaining both high productivity and adaptability across varying operational conditions
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
This solution effectively reduces rolling motion by ensuring the wave propagation is in antiphase with the vessel's rolling motion, providing improved stability and comfort with significantly reduced energy input compared to gyroscopic stabilization systems.
Implementation Method 1
a wave propagating on a surface of the liquid is at least partially in antiphase to the rolling motion of the vessel for reducing a magnitude of the rolling motion
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A roll dampening apparatus (200) for reducing rolling motion in an ocean vessel (100) includes an elongate tank (20) disposed transversely across the vessel (100) partially filled with a liquid (10). A control arrangement (210, 220) monitors in operation a roll angle (or) of the vessel (100) and controls dynamically an effective depth (d) of the liquid (10) so that a wave (30) propagating on a surface of the liquid (10) is at least partially in antiphase to the rolling motion of the vessel (100) for reducing a magnitude of the rolling motion.