Alternating Helicoid Cell Structure for Acoustic Damping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing acoustic panel designs face limitations in effectively damping a wide range of audible frequencies due to surface area constraints and manufacturing challenges, often resulting in designs that employ only a single or double degree of freedom, which fail to meet desired acoustic performance objectives.
Innovation Solution
A novel alternating clockwise and counterclockwise helicoid cell structure is introduced, featuring coaxial inner and outer cavities with equal-volume chambers rotated in opposite directions, allowing for efficient sound wave attenuation across a broad frequency range, and can be easily replicated and integrated into various acoustic panel dimensions using additive manufacturing techniques.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the surface area of the acoustic panel is increased to improve acoustic performance, then the ability to dampen a wide range of frequencies is improved, but manufacturing complexity and material forming challenges increase
Solution Approach 1:
The patent implements nested cavities where inner cavities are positioned within outer cavities, creating a multi-layered helicoid structure. This nesting approach increases the effective acoustic treatment volume and frequency damping capability within a compact footprint, resolving the contradiction by providing enhanced acoustic performance without proportionally increasing overall surface area or manufacturing complexity
Solution Approach 2:
The acoustic panel is segmented into multiple discrete helicoid cells, each containing multiple cavities with specific dimensions tuned to different frequency ranges. This segmentation allows the panel to dampen a broad frequency spectrum through the collective action of multiple specialized cells, improving acoustic performance while maintaining manageable manufacturing complexity through modular construction
2Ease of manufacture
If acoustic panels are designed with single or double degree of freedom to simplify manufacturing, then ease of manufacture is improved, but the ability to dampen wide range of frequencies is worsened
Solution Approach 1:
The helicoid cell structure serves multiple acoustic functions simultaneously: the outer cavities dampen certain frequency ranges while inner cavities dampen other ranges, and the helicoidal geometry provides both structural integrity and acoustic treatment. This multi-functionality allows a single cell design to achieve broad-spectrum damping without requiring multiple specialized components, maintaining ease of manufacture while improving acoustic performance
Solution Approach 2:
The nested cavity configuration enables a single helicoid cell to function across multiple frequency ranges, with inner and outer cavities contributing differently to the overall acoustic response. This nested multi-functional design allows one manufacturable cell structure to replace what would otherwise require multiple separate single-degree-of-freedom panels, thereby improving acoustic performance while preserving manufacturing simplicity
3Volume of moving object
If the acoustic panel uses compact design to reduce space, then volume efficiency is improved, but the surface area available for damping sound waves is reduced
Solution Approach 1:
The patent transitions from two-dimensional surface-based acoustic treatment to three-dimensional volumetric treatment through the helicoid cell structure with nested cavities. This dimensional change allows the panel to utilize internal volume effectively for acoustic damping, achieving compact space efficiency while maintaining adequate acoustic treatment capability through the three-dimensional cavity architecture rather than relying solely on surface area
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 helicoid cell structure effectively dampens sound waves across a wide range of frequencies, providing improved acoustic performance while being lightweight and space-efficient, and can be easily manufactured and integrated into various acoustic panel applications.
Implementation Method 1
The helicoid cell structure effectively dampens sound waves across a wide range of frequencies
Implementation Method 2
each of the inner chambers being rotated in a first direction around the central axis by at least p rotations per 2.5cm (per inch) from the second cavity entrance side to the cell structure floor
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
An alternating clockwise and counterclockwise helicoid cell structure for use in acoustic panels. The cell structure geometry may be easily replicated and tiled using additive manufacturing. The cell structure has at least an outer cavity and an inner cavity. The cavities are coaxial, share the same height, same entrance side, and same cell structure floor. The inner cavity includes a number of equal-volume inner chambers rotated uniformly in a first direction around the shared central axis; and the outer cavity includes a second number of equal-volume outer chambers rotated uniformly in an opposite direction to the first direction around the shared central axis. In various embodiments, one or more perforated baffles may extend, internally, across a chamber, perpendicular to direction of sound waves at the location of the perforated baffle. In various embodiments, one or more port openings from the outer cavity to the inner cavity may be present.