Pressurized Pendulum Mass Damper for Low-Frequency Tower Oscillations
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional tuned mass dampers struggle to effectively dampen low-frequency oscillations below 2 Hz, particularly in high, narrow structures like wind-turbine towers, due to limitations in mass and pendulum length, requiring significant effort and space for achieving desired frequencies.
Innovation Solution
A pendulum-tuned mass damper with a pressurized support device that adjusts the weight of the oscillation mass using a gas-air volume, allowing for selective frequency adaptation by raising or lowering the mass, thereby matching the natural frequency of the oscillation system.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If a conventional pendulum is used to achieve low frequencies below 0.15 Hz, then the required pendulum length exceeds 11 m, but this requires great effort and large space in practice
Solution Approach 1:
The patent employs a counter-pendulum mechanism that acts from below on the pendulum mass to reduce its effective weight. By applying an upward force through the support device, the system achieves lower oscillation frequencies without requiring excessively long pendulum cables, thus resolving the contradiction between achieving low frequencies and maintaining practical pendulum dimensions
Solution Approach 2:
The patent introduces a dynamically adjustable support device that can modify the effective weight of the pendulum mass during operation. This dynamic adjustment capability allows the system to adapt to varying frequency requirements without changing the physical pendulum length, enabling low-frequency operation within compact spatial constraints
2Adaptability or versatility
If the stiffness of radial springs is changed to achieve low frequencies with a rolling mass, then frequency adjustment is possible, but this is associated with significant effort
Solution Approach 1:
The patent replaces the mechanical spring stiffness adjustment mechanism with a pneumatic or hydraulic support device that applies vertical forces to the pendulum mass. This substitution simplifies the adjustment process by using pressure-controlled fluid systems instead of complex mechanical spring modification mechanisms, reducing the effort required for frequency adaptation
Solution Approach 2:
The patent changes the physical state or parameters of the support system from fixed mechanical spring stiffness to variable pneumatic/hydraulic pressure. By adjusting the pressure parameters of the gas-air volume in the support device, the system achieves frequency adaptability without modifying the physical structure or stiffness of mechanical components
3Object-affected harmful factors
If a pulse damper is used to achieve low frequencies, then damping is possible, but approximately three times the mass is required compared to pendulum dampers
Solution Approach 1:
The patent uses the counter-pendulum support device to reduce the effective weight that the pulse damper must handle. By applying upward forces through the support mechanism, the system decreases the apparent mass burden on the damping components, enabling effective low-frequency damping with reduced overall mass compared to conventional pulse dampers
4Object-affected harmful factors
If a pulse damper is used for low frequencies, then damping can be achieved, but the damper must be aligned exactly horizontally, which cannot always be avoided in practice
Solution Approach 1:
The patent employs a dynamically adjustable support device that can compensate for misalignment conditions. By actively adjusting the vertical forces applied to the pendulum mass, the system maintains effective damping performance even when the damper is not perfectly horizontally aligned, thus eliminating the strict alignment requirement that plagues conventional pulse dampers
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
Enables efficient damping of low-frequency oscillations between 0.15 and 1.5 Hz in high, narrow structures with minimal space and effort, providing adaptable damping solutions for variable frequency conditions.
Implementation Method 1
a pressurized and pressure-controlled support device (7), which can increase or reduce the weight of the oscillation mass (1) by raising or lowering
Implementation Method 2
the support device is an integral component of the second pendulum rod (5), or the support device functions as a pendulum rod
Implementation Method 3
A pendulum functions due to gravity acting on the mass. The higher the weight caused by gravity is, the higher the natural frequency is with the same pendulum length
Data Source
AI summary
The invention relates to a new type of tuned mass damper which is suitable in particular for damping oscillations of a low frequency, and can thus be used preferably as a construction damper when building or siting high, narrow structures, such as wind-turbine towers. The invention relates in particular to a pendulum oscillation damper having a first pendulum, to which the mass is attached, and a second pendulum, which is formed by a spring-like support device of a different design and is operated using a gas-air volume such that, with the aid thereof, the frequency of the oscillation system can be adapted and adjusted.