Accurate and efficient prediction of acoustical performance of noise barriers against transport noise pollution

Abstract

An improved acoustical wave propagator (I_AWP) technique with high-order absorbing boundary technique is introduced to evaluate the acoustical wave interaction for noise barriers, providing the dual benefit of preserving high numerical accuracy (boundary conditions have been properly treated) and obtaining high computational efficiency (using a larger time step in the calculation). The aim is to establish a framework for effective design of noise barriers based on (a) in the time-domain, the evolution of wave propagation and analyses of acoustical-structure interaction, then a good understanding of time-domain acoustical wave diffraction (one key noise abatement mechanism) can be achieved, and (b) in the frequency-domain, the effects of noise barriers with different structures and noise sources at different locations on sound pressure distribution, especially noise barriers with a simple smart structure (membranes) are investigated in detail. These investigations produce a database for effective and optimal design of noise barriers. More importantly, the outcome can provide a deep insight to the acoustical performance of noise barriers in reducing noise pollution in urban environments and other applications.