Adjustable Sound-Damping Container for Variable-Speed Engine Noise
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional sound-damping systems struggle to effectively damp low-frequency noise generated by variable-speed engines due to their high natural frequency, requiring large dimensions or limited frequency range effectiveness.
Innovation Solution
A sound-damping arrangement with a line element between the inlet and outlet lines, featuring an adjusting device that continuously alters the passage's geometry and material composition to match the engine's noise frequency, using actuators and a control unit to adjust the configuration and acoustic characteristics of the sound-damping container.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If conventional sound-damping containers are made large enough to damp low-frequency noise, then noise damping effectiveness is improved, but device dimensions increase
Solution Approach 1:
The patent applies dynamics by making the sound-damping container's natural frequency adjustable rather than fixed. The resonance frequency can be dynamically changed to match the varying frequency of low-frequency noise from variable-speed engines, allowing effective damping without requiring large dimensions. This is achieved through mechanisms that alter the container's acoustic properties in real-time.
Solution Approach 2:
The patent changes the parameter of natural frequency of the sound-damping container to match the noise frequency. By adjusting the resonance frequency parameter of the container to correspond to the dominant low-frequency noise frequency, the system achieves effective damping with compact dimensions. This parameter matching is continuously adapted as engine speed varies.
2Object-affected harmful factors
If conventional sound-damping containers are made large, then low-frequency noise damping is improved, but pressure drop increases
Solution Approach 1:
The patent uses dynamics to adjust the sound-damping container's resonance frequency to match varying noise frequencies, eliminating the need for large fixed-dimension containers. This dynamic adaptation allows effective low-frequency noise damping while maintaining compact dimensions that minimize pressure drop across the exhaust system.
3Object-affected harmful factors
If resonance-type silencers are used for narrow frequency range damping, then noise damping effectiveness is improved, but adaptability to variable speed engines deteriorates
Solution Approach 1:
The patent applies dynamics by enabling the sound-damping container to actively adjust its resonance frequency in response to varying engine speeds. This dynamic frequency adjustment allows the container to maintain high damping effectiveness across a wide frequency range, adapting to the variable-speed operation of modern engines while preserving the benefits of resonance-type damping.
Solution Approach 2:
The patent achieves universality by designing a sound-damping container that can effectively damp noise across multiple frequency ranges through adjustable resonance. The system serves multiple functions by adapting to different operating conditions and frequency requirements, making it suitable for variable-speed engines while maintaining high damping effectiveness.
4Object-affected harmful factors
If the natural frequency of the sound-damping container is lowered to match low-frequency noise, then noise damping effectiveness is improved, but container dimensions must increase
Solution Approach 1:
The patent resolves this contradiction by making the natural frequency adjustable rather than fixed by geometry alone. The sound-damping container can dynamically lower its resonance frequency to match low-frequency noise without requiring large dimensions, as the frequency adjustment is achieved through active mechanisms rather than passive geometric scaling.
Solution Approach 2:
The patent changes the natural frequency parameter of the sound-damping container to match the low-frequency noise frequency. By adjusting this parameter through active mechanisms rather than increasing container volume, the system achieves effective low-frequency damping while maintaining compact dimensions.
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 effective damping of low-frequency noise across varying engine speeds with a compact design, as the natural frequency of the sound-damping container is dynamically adjusted to match the noise frequency, enhancing noise reduction without significant pressure drop.
Implementation Method 1
the natural frequency of the sound-damping container is dynamically adjusted to match the noise frequency
Implementation Method 2
sound-damping container which has a natural frequency which corresponds to the frequency of the low-frequency noise
Data Source
Figure 1~2
AI summary
The present invention relates to a sound-damping arrangement. The sound-damping arrangement comprises a sound-damping container (3) with an internal space (3a), an inlet line (2) adapted to leading a fluid to the container (3) from a machine (1) which generates during operation a dominant noise with a frequency which is related to the speed of the machine, and an outlet line (4) adapted to leading the fluid out from the container (3). The arrangement comprises also a line element (5) which has an internal passage which connects the inlet line (2) and the outlet line (4) at a position in the vicinity of the sound-damping container (3), and an adjusting device (5a-d, 6- 9) adapted to adjusting the configuration of the passage and hence the acoustic characteristics of the sound-damping container so that the latter continuously assumes a natural frequency corresponding to the dominant sound frequency generated by the machine at its current speed.