What is a sound barrier? Inserting an obstruction between the sound source and receiver to significantly attenuate the propagation of sound waves, thereby reducing the noise impact in a certain area where the receiver is located, is called a #sound barrier.
Starting from the center of the sound source, sound waves diverge and propagate in all directions. The influence range of sound waves is like a sphere. When sound waves encounter a sound barrier, they will propagate along three paths: diffraction, transmission, and reflection.
Diffraction of sound waves refers to the phenomenon in which some sound waves will bypass obstacles and continue to propagate when they encounter obstacles during the propagation process. Diffraction of sound waves can cause sound to form a shadow zone behind obstacles, resulting in a significant decrease in volume. When obstacles are large, the volume in the area behind them will significantly decrease. The phenomenon of projection refers to the transmission of noise through sound barriers to sensitive points. Reflection is the process of sound waves being reflected multiple times by two sound barriers before being transmitted to a sensitive point. The energy of sound waves mainly propagates along these three paths, and the insertion energy loss of sound barriers mainly depends on the distribution of sound energy emitted by the sound source along these three paths.
The diffraction propagation path prevents sound waves from directly reaching sensitive points, and the area behind the sound barrier where sound waves cannot directly travel is called the “acoustic shadow zone”. The expected noise reduction effect of the sound barrier is within the range of the “sound shadow zone”. The larger the “sound shadow zone”, the larger the impact area of sound waves, and the smaller the noise impact that the receiver can accept.
We have the following suggestions for improving the #noise reduction performance of sound barriers:
1.The position of the sound barrier should be as close as possible to the sound source, which is beneficial for increasing the shadow area of the barrier and thus improving its sound attenuation effect.
2.The higher the sound barrier, the larger the shadow area, and the greater the attenuation effect on sound. However, if the sound barrier is too high, it may cause structural, environmental, and cost issues, so the sound barrier itself cannot be made too high. Therefore, when designing sound barriers, it is necessary to adapt to local conditions, utilize terrain and topography, increase the effective height of the sound barrier, and achieve the best effect.
3. Extending a eaves towards the sound source at the top of the sound barrier is equivalent to moving the entire sound barrier towards the sound source, which can effectively increase the depth and area of the shadow area.
Post time: Oct-17-2024
