Three dimensional quasi-periodic noise barriers

Two dimensional noise barrier studies investigate the insertion loss in the shadow zone of an infinite noise barrier for a coherent line source. Such models are often preferred to avoid the high computational cost of three dimensional models. The major limitation of two dimensional barrier models is the constant cross section of the barrier in the third direction. This paper presents a new solution to evaluate the performance of 3D noise barriers that do not have a constant cross section. A quasi-periodic noise barrier model is developed to reduce the size of a 3D infinite boundary element model and thereby reduce the computational time. Different quasi-periodic noise barrier designs are developed and their acoustic performance at different frequencies and receiver positions are compared.