Soundproof structural body
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing soundproof structures face challenges in compactly absorbing low-frequency sound and efficiently absorbing peak sounds, particularly due to spatial restrictions and the need for multiple resonators, which limits miniaturization and compact design.
Innovation Solution
A soundproof structure body with a resonance type soundproof structure where the phase difference between reflected waves from the resonance structure and the opening end is optimized, allowing for high absorption with a single resonance structure, and the structure is designed to effectively offset reflected waves, achieving high absorption with a smaller size.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple resonators are disposed in parallel to increase sound absorbance, then sound absorbance is improved, but device complexity and size increase
Solution Approach 1:
The invention changes the key parameter from quantity of resonators to spatial arrangement and phase relationship. By optimizing the interval between resonators and their relative positions, a single resonator configuration achieves the same absorbance effect that previously required multiple resonators, thus resolving the contradiction between sound absorbance and device complexity
Solution Approach 2:
The invention transitions from considering only the number of resonators (one-dimensional quantity) to incorporating spatial arrangement, interval distances, and phase differences (multi-dimensional parameters). This dimensional expansion allows achieving high absorbance through optimized positioning rather than simply increasing the number of components
2Reliability
If a silencer box with larger cross-sectional area is used to absorb low frequency sound, then low frequency sound absorption is improved, but device size increases
Solution Approach 1:
The invention changes the approach from increasing cross-sectional area to optimizing the interval parameter between the resonator and opening end. This parameter optimization enables effective low-frequency sound absorption while maintaining a compact cross-sectional area, thus resolving the contradiction between absorption performance and device size
Solution Approach 2:
The invention applies local optimization by specifically controlling the interval distance between the resonator and opening end, rather than uniformly increasing the entire silencer box size. This localized parameter control achieves low-frequency absorption without proportionally increasing the overall device dimensions
3Reliability
If the interval between resonators is optimized for peak sound absorption, then peak sound absorbance is improved, but absorption effectiveness at other frequencies decreases
Solution Approach 1:
The invention uses preliminary anti-action by introducing a reflected wave that is phase-opposed to the direct wave from the resonator. This pre-planned interference pattern creates a null point at the opening end for peak frequencies, while the spatial distribution of this interference effect provides broader frequency range absorption, thus resolving the contradiction between peak sound absorbance and frequency range adaptability
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 solution enables efficient absorption of sound across a wide frequency range, reducing reflection and achieving high absorption with a minimal number of resonance structures, thus allowing for compact and effective soundproofing in constrained spaces.
Implementation Method 1
resonance type soundproof structure (a resonance body such as a Helmholtz resonator, an air column resonance cylinder, and a film vibration type resonance structure)
Implementation Method 2
a phase difference θ, at an upstream of the resonance type soundproof structure, between a reflected wave in the resonance type soundproof structure and a reflected wave of a transmitted wave transmitted through the resonance type soundproof structure and reflected by the opening portion
Data Source
Figure 1~2
Figure 3~5
Figure 6~8
AI summary
In a soundproof structure body including a tubular tube body having an opening portion, and a resonance type soundproof structure, in which a phase difference θ, at an upstream of the resonance type soundproof structure, between a reflected wave in the resonance type soundproof structure and a reflected wave of a transmitted wave transmitted through the resonance type soundproof structure and reflected by the opening portion satisfies Inequation |θ - π| ≤ π/3 with respect to a resonance frequency of the resonance type soundproof structure. This soundproof structure body can effectively offset a reflected wave from a resonance type soundproof structure body by opening end reflection by appropriately specifying positions of the resonance type soundproof structure and the opening end portion of a duct, a tube line, or the like to improve an absorbance of a single resonance type soundproof structure.