Research on the Arrangement of Additional Source for Large Space Protection of an Active Noise Barrier

Abstract

When active noise control technology is applied to traffic noise control, additional sources are often added to the facade of the barrier, and error sensors are placed in the protected area. The noise reduction effect in the area without error sensors is often ignored. In this paper, the effect of the additional source configuration on the sound field in the space without error sensors is researched. By analyzing the directivity and distribution of the sound field at the top of the barrier under various conditions, it is believed that the optimal location of the additional source is related to the height of the primary source and the barrier. An approximate model is established to evaluate the optimal location of the additional source for achieving a good noise reduction effect in a large space. Experiments are also carried out to verify the model. The conclusions are beneficial for improving the noise reduction effect in the area higher than the barrier and without error microphones.