Tower Enclosure Outer-Surface Absorber for Wind-Induced Vibration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The installation of wind turbines is restricted by regional wind conditions, leading to safety risks and delays due to vibrations and resonance issues caused by vortex-induced vibrations and fluctuating wind forces.
Innovation Solution
A frequency mixing and absorbing device is installed on the outer surface of the wind turbine tower, comprising deformable bodies that absorb and homogenize fluctuating energy through volume changes, reducing downwind resistance and suppressing vibrations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional foam materials are used for sound absorption, then manufacturing is simple, but sound absorption effectiveness is insufficient at certain frequencies
Solution Approach 1:
The patent combines conventional foam material with a frequency mixing absorber layer having different acoustic impedance and flow resistivity characteristics. This composite structure allows the foam to provide baseline sound absorption while the frequency mixing absorber enhances effectiveness at specific frequencies, resolving the contradiction between manufacturing simplicity and sound absorption effectiveness.
Solution Approach 2:
The frequency mixing absorber is applied selectively at the outer surface of the foam material rather than throughout the entire structure. This localized approach maintains the overall simplicity of manufacturing while concentrating the enhanced sound absorption properties where they are most needed for problematic frequencies.
2Reliability
If complex acoustic treatment structures are used, then sound absorption effectiveness improves, but device complexity increases
Solution Approach 1:
The frequency mixing absorber is integrated directly onto the outer surface of the existing foam material, merging two functional layers into a single composite acoustic treatment system. This approach improves sound absorption effectiveness without requiring separate complex structures or multiple independent components.
Solution Approach 2:
The frequency mixing absorber layer serves multiple functions: it provides enhanced sound absorption at specific frequencies, acts as a protective outer layer, and maintains compatibility with the underlying foam structure. This multi-functionality reduces the need for additional specialized components, thereby limiting complexity increases.
3Reliability
If frequency mixing absorber is added to improve sound absorption, then sound absorption effectiveness improves, but manufacturing complexity increases
Solution Approach 1:
The frequency mixing absorber is manufactured as a pre-formed layer or coating that can be applied to the foam material in advance. This preliminary preparation allows the frequency mixing absorber to be integrated into the acoustic treatment system without adding significant complexity to the final assembly or installation process.
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 effectively reduces downwind vibrations and enhances stability during hoisting and operation by consuming and diffusing fluctuating energy, ensuring safety and reducing installation delays.
Implementation Method 1
sound absorption material having a flow resistivity between 10,000 and 30,000 Rayls
Implementation Method 2
converting acoustic energy into thermal energy
Implementation Method 3
porous structure of the frequency mixing absorber
Implementation Method 4
dissipating energy through friction
Data Source
Figure 1-1
Figure 1-2
Figure 2
AI summary
An enclosure with a frequency mixing and absorbing device on an outer surface is provided. The frequency mixing and absorbing device includes a deformable body located on an outer surface of the enclosure, the deformable body includes a flexible body and/or an elastic body, the flexible body is a flexible hollow body or a flexible solid body, the elastic body is an elastic hollow body or an elastic solid body; and the deformable body is deformable under an action of an incoming flow. When the direction of the incoming flow is from left to right, it acts on the deformable body at a windward side, that is, the change of pressure will be converted into the volume change of the deformable body. In this way, the fluctuating energy of the incoming flow can be absorbed and stored by the deformation of the deformable body, to realize disordering of the fluctuating energy, and the fluctuating energy is transferred to the volume change. During the process that the volume change of the deformable body is transferred downstream, the fluctuating energy is consumed and submerged, instead of directly acting on the outer surface of the enclosure. Therefore, with the arrangement of the deformable body, the fluctuating excitation is self-consumed and submerged, the downwind resistance is reduced, and thereby suppressing the vibration.